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UV-Spectrophotometric Determination of the Active Pharmaceutical Ingredients Meloxicam and Nimesulide in Cleaning Validation Samples With Sodium Carbonate

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20 January 2023

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25 January 2023

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Abstract
The spectrophotometric methods of determination of the active pharmaceutical ingredients meloxicam and nimesulide were reviewed, and a simple UV-spectrophotometric method for the determination of these active pharmaceutical ingredients in industrial equipment cleaning validation samples were proposed. The methods are based on extraction of the residual quantities of meloxicam and numesulide from the manufacturing equipment surface by the concentrated sodium carbonate solution, and the subsequent UV-spectrophotometric determination of the basic forms of the drugs at the wavelength of 362 nm for meloxicam and at 397 nm for nimesulide. The calibration graphs are linear in the range from 5 to 25 mg/L of both nimesulide and meloxicam, the molar attenuation coefficients are 6100 m2/mol for nimesulide and 9100 m2/mol for meloxicam, the limit of detection is 0.8 mg/L for nimesulide and 1.9 mg/L for meloxicam, the limit of quantification is 2.5 mg/L for nimesulide and 5.8 mg/L for meloxicam, the methods are selective with respect to the common excipients, show a good accuracy (the relative uncertainty does not exceed 4%) and precision (the relative standard deviation does not exceed 5%), do not require lengthy sample preparation and sophisticated laboratory equipment and are suitable for the routine analysis of cleaning validation samples.
Keywords: 
meloxicam
;  
nimesulide
;  
UV-spectrophotometric determination
;  
cleaning validation samples
Subject: 
Chemistry and Materials Science  -   Analytical Chemistry

Introduction

Meloxicam (IUPAC name: 4-Hydroxy-2-methyl-N-(5-methyl-2-thiazolyl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide, CAS number: 71125-38-7) and nimesulide (IUPAC name: N-(4-Nitro-2-phenoxyphenyl)methanesulfonamide, CAS number: 51803-78-2) are both the widely used nonsteroidal anti-inflammatory drugs. Meloxicam was developed for the treatment of rheumatoid arthritis and osteoarthritis [1,2], and nimesulide was found to be effective in reducing pain associated with osteoarthritis, cancer, thrombophlebitis, oral surgery and dysmenorrhea [3,4].
When several pharmaceuticals are manufactured on the same production line, pharmaceutical product can be contaminated by other pharmaceutical products, by cleaning agents, by microorganisms or by other materials. The procedure of cleaning the industrial equipment, apparatus as well as the processing area is required to effectively remove the potentially dangerous substances from it. However, it is necessary to validate the cleaning procedures to ensure safety, efficacy, quality of the subsequent batches of drug product [5]. Historically, cleanliness of equipment manufacturing is validated and verified using direct swabbing of the equipment and subsequent analytical testing of the swab extracts [6]. The quantitative determination of meloxicam and nimesulide is possible using a variety of methods including all types of chromatographic, spectroscopic and voltammetric techniques [7]. A routine determination of the pharmaceutical ingredients in the swab extracts however should ideally be performed directly in the production area, should not require comprehensive equipment, and the method should be rapid and simple. Therefore, the method utilising UV-visible spectroscopy is preferred. The existing spectrophotometric methods for the determination of nimesulide [8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32] are summarized in Table 1, and those for meloxicam [32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63] in Table 2.
These methods were checked for rapidness, simplicity and usage of the reagents common for pharmaceutical laboratory, and it was found that the simplest methods that allow the determination of nimesulide and meloxicam content directly in the aqueous solutions without lengthy phase separation steps and sample or reagent preparation, and that use only very common reagents available in any pharmaceutical laboratory, are based on the formation of the coloured deprotonated forms of nimesulide and meloxicam in alkaline environments. Both these active pharmaceutical ingredients exhibit an acid-base behaviour, and in the presence of NaOH form the intensively coloured yellow solutions. However, the usage of the concentrated alkalis for swabbing the drug residues from the manufacturing equipment surface is not favourable, because the alkalis themselves are toxic and may contaminate the subsequent products. The solution of sodium carbonate is much less toxic, but its usage for the determination of nimesulide and meloxicam in aqueous solution was not yet reported. Therefore, this study aims to develop a method for the spectrophotometric determination of nimesulide and meloxicam in industrial equipment cleaning validation samples using sodium carbonate.

Materials & Methods

Reagents and equipment. Sodium carbonate (chemically pure, 99.8%) was purchased from Lenreaktiv. Nimesulide (EP CRS grade), meloxicam (EP CRS grade), polyvinylpyrrolidone K-17 (USP RS grade), lactose monohydrate (reagent grade, sodium starch glycolate (reagent grade), colloidal silicon dioxide (USP RS grade), microcrystalline cellulose (reagent grade), talcum (USP RS grade) and magnesium stearate (reagent grade) were purchased from Sigma-Aldrich. Different tablets containing nimesulide and meloxicam were purchased from the local market. The flat plates made of stainless steel 12Х12Н10Т were used to model the cleaning of industrial equipment. The analytical balance Sartorius Cubis MSA 225P-ICE-DI was used for weighting. The various micropipettes manufactured by Thermo Fisher Scientific were used for taking aliquots. The spectrophotometer Mettler Toledo UV7 was used for colorimetric measurements. The chemical glassware of the 2nd grade was used. Water for preparation of solutions was twice distillated and then deionised with Sartorius Arium Pro VF Ultrapure Water system.
Preparation of the 10% solution of sodium carbonate. 200.00 g of sodium carbonate was weighted, dissolved in ca. 1900 ml of water with the help of heating, the solution was cooled, transferred to the 2000 ml volumetric flask, and the volume of the solution was adjusted by water.
Preparation of the 50 mg/L stock solution of nimesulide. 0.0125 g of nimesulide was weighted, dissolved in ca. 200 ml of 10% solution of sodium carbonate, the solution was transferred to the 250 ml volumetric flask and the volume of the solution was adjusted by 10% solution of sodium carbonate.
Preparation of working solutions of nimesulide. The working solutions of nimesulide with different concentrations ranging from 5 to 25 mg/L were prepared by appropriate dilution of the stock solution with 10% solution of sodium carbonate. The working solutions were prepared daily.
Preparation of sample solutions of nimesulide from tablets. The tablets available on the Russian local market contain 100 mg of nimesulide. The content of ten tablets was thoroughly mixed in a porcelain mortar, collected into a beaker and dissolved in ca. 800 ml of 10% solution of sodium carbonate, the solution was transferred to the 1000 ml volumetric flask, dissolved in 10% solution of sodium carbonate and the volume of the solution was adjusted by 10% solution of sodium carbonate. The aliquot of 5.0 ml of the prepared solution was taken, transferred to the 500 ml volumetric flask, and the volume of the solution was adjusted by 10% solution of sodium carbonate. The concentration of nimesulide in the resulting solution equals 10 mg/L.
Preparation of swab extracts of nimesulide from working solution. The aliquot of 10.0 ml of the prepared working solution with the concentration of nimesulide equal to 15 mg/L was taken, placed onto the flat plates made of stainless steel 12Х12Н10Т, and allowed to dry in the fume hood. In the test tubes 10.0 ml of 10% solution of sodium carbonate was prepared. The cotton swab was dunked with 10% solution of sodium carbonate, and the plates were swabbed several times during 2 minutes, the used swabs were immersed into the test tubes with 10% solution of sodium carbonate and mixed thoroughly during 5 minutes, the resulting solutions were transferred to the 10 ml volumetric flasks, and the volumes of the solutions were adjusted by 10% solution of sodium carbonate. The expected concentration of nimesulide in the swab extract is equal to 15 mg/L.
Preparation of swab extracts of nimesulide from tablets. The content of ten tablets was thoroughly mixed in a porcelain mortar, collected into a beaker and dissolved in ca. 800 ml of 10% solution of sodium carbonate, the solution was transferred to the 1000 ml volumetric flask, dissolved in 10% solution of sodium carbonate and the volume of the solution was adjusted by 10% solution of sodium carbonate. The aliquot of 5.0 ml of the prepared solution was taken, transferred to the 500 ml volumetric flask, and the volume of the solution was adjusted by 10% solution of sodium carbonate. The aliquot of 10.0 ml of the prepared solution with the concentration of nimesulide equal to 10 mg/L was taken, placed onto the flat plate made of stainless steel 12Х12Н10Т, and allowed to dry in the fume hood. In the test tube 10.0 ml of 10% solution of sodium carbonate was prepared. The cotton swab was dunked with 10% solution of sodium carbonate, and the plate was swabbed several times during 2 minutes, the used swab was immersed into the test tube with water and mixed thoroughly during 5 minutes, the resulting solution was transferred to the 10 ml volumetric flask, and the volume of the solution was adjusted by 10% solution of sodium carbonate. The expected concentration of nimesulide in the swab extract equals 10 mg/L.
Preparation of the 50 mg/L stock solution of meloxicam. 0.0125 g of meloxicam was weighted, dissolved in ca. 200 ml of 10% solution of sodium carbonate, the solution was transferred to the 250 ml volumetric flask and the volume of the solution was adjusted by 10% solution of sodium carbonate.
Preparation of working solutions of meloxicam. The working solutions of meloxicam with different concentrations ranging from 5 to 25 mg/L were prepared by appropriate dilution of the stock solution with 10% solution of sodium carbonate. The working solutions were prepared daily.
Preparation of sample solutions of meloxicam from tablets. The tablets available on the Russian local market contain 15 mg of meloxicam. The content of ten tablets was thoroughly mixed in a porcelain mortar, collected into a beaker and dissolved in ca. 800 ml of 10% solution of sodium carbonate, the solution was transferred to the 1000 ml volumetric flask, dissolved in 10% solution of sodium carbonate and the volume of the solution was adjusted by 10% solution of sodium carbonate. The aliquot of 50.0 ml of the prepared solution was taken, transferred to the 500 ml volumetric flask, and the volume of the solution was adjusted by 10% solution of sodium carbonate. The concentration of meloxicam in the resulting solution equals 15 mg/L.
Preparation of swab extracts of meloxicam from working solution. The aliquot of 10.0 ml of the prepared working solution with the concentration of meloxicam equal to 10 mg/L was taken, placed onto the flat plates made of stainless steel 12Х12Н10Т, and allowed to dry in the fume hood. In the test tubes 10.0 ml of 10% solution of sodium carbonate was prepared. The cotton swab was dunked with 10% solution of sodium carbonate, and the plates were swabbed several times during 2 minutes, the used swabs were immersed into the test tubes with 10% solution of sodium carbonate and mixed thoroughly during 5 minutes, the resulting solutions were transferred to the 10 ml volumetric flasks, and the volumes of the solutions were adjusted by 10% solution of sodium carbonate. The expected concentration of meloxicam in the swab extract is equal to 10 mg/L.
Preparation of swab extracts of meloxicam from tablets. The content of ten tablets was thoroughly mixed in a porcelain mortar, collected into a beaker and dissolved in ca. 800 ml of 10% solution of sodium carbonate, the solution was transferred to the 1000 ml volumetric flask, dissolved in 10% solution of sodium carbonate and the volume of the solution was adjusted by 10% solution of sodium carbonate. The aliquot of 50.0 ml of the prepared solution was taken, transferred to the 500 ml volumetric flask, and the volume of the solution was adjusted by 10% solution of sodium carbonate. The aliquot of 10.0 ml of the prepared solution with the concentration of meloxicam equal to 15 mg/L was taken, placed onto the flat plate made of stainless steel 12Х12Н10Т, and allowed to dry in the fume hood. In the test tube 10.0 ml of 10% solution of sodium carbonate was prepared. The cotton swab was dunked with 10% solution of sodium carbonate, and the plate was swabbed several times during 2 minutes, the used swab was immersed into the test tube with water and mixed thoroughly during 5 minutes, the resulting solution was transferred to the 10 ml volumetric flask, and the volume of the solution was adjusted by 10% solution of sodium carbonate. The expected concentration of meloxicam in the swab extract equals 15 mg/L.
General procedure for the determination of nimesulide. The absorbances of the working or sample solution of nimesulide at the wavelength of 397 nm in the glass cuvette with the optical path length 1 cm were measured against the 10% solution of sodium carbonate.
General procedure for the determination of meloxicam. The absorbances of the working or sample solution of meloxicam at the wavelength of 362 nm in the glass cuvette with the optical path length 1 cm were measured against the 10% solution of sodium carbonate.

Results

Selection of the wavelength. The working solution of nimesulide with the concentration 25 mg/L and the working solution of meloxicam with the concentration 20 mg/L were prepared and their spectra against the 10% sodium carbonate solution were recorded in the quartz cuvette with the optical path length 1 cm at the wavelengths ranging from 200 to 500 nm. The spectrum of nimesulide is presented in Figure 1 and it exhibits a maximum at 397 nm, the spectrum of meloxicam is presented in Figure 2 and it exhibits a maximum at 362 nm. Both maxima wavelengths coincide with those of the solutions of respective drugs in sodium hydroxide.
Selection of sodium carbonate solution concentration. The working solutions of nimesulide with concentration 25 mg/L and the working solution of meloxicam with concentration of 20 mg/L using the sodium carbonate solution with different concentrations (1, 2, 5, 10, 15 and 20%) as the solvent were prepared, and their absorbances at respective wavelengths against respective solvents were measured. The results are presented in Figure 3. According to the data, the 10% sodium carbonate solution was selected as the solvent for all future experiments.
Construction of the calibration graph. The working solutions of nimesulide and meloxicam with different concentrations ranging from 5 to 25 mg/L were prepared. The absorbances of prepared solutions were measured against the 10% solution of sodium carbonate at the corresponding wavelengths. The results are presented in Figure 4.
Analytical performance. The analytical performance of the method was determined in accordance with the State Pharmacopoeia of the Russian Federation guidelines. The method was tested for linearity, limits of detection and quantification, selectivity, accuracy, and inter- and intra-day precision.
Linearity. According to Figure 4, the dependences of the absorbances of the drug solutions at the corresponding wavelengths on the drug concentration are linear in the range from 5 to 25 mg/L. The regression analysis was performed using the least-squares technique [64]. Additionally, the Ringbom’s optimum range [65,66,67], the molar attenuation coefficient and the Sandell’s sensitivity coefficient [68] were calculated. The parameters of the regression equation are listed in Table 3.
Limit of detection and limit of quantification. The limit of detection and the limit of quantification of the method [69,70,71] were calculated. The values are presented in Table 3.
Selectivity with respect to common excipients. According to the Russian State Register of Pharmaceutical Products, tablets of nimesulide contain lactose monohydrate, sodium starch glycolate, polyvinylpyrrolidone K-17, magnesium stearate, microcrystalline cellulose, and colloidal silicon dioxide as the common excipients. Tablets of meloxicam contain lactose monohydrate, talcum, magnesium stearate, and microcrystalline cellulose as the common excipients. The possible interference of these excipients was studied. For that the 1 g/l water solutions of polyvinylpyrrolidone, lactose monohydrate, sodium starch glycolate, and the 1 g/l suspensions of magnesium stearate, microcrystalline cellulose, and colloidal silicon dioxide in 10% solutions of sodium carbonate were prepared. The solutions were left for 60 minutes, and their absorbances at 362 and 397 nm against the sodium carbonate solution were measured. No development of the yellow colour was observed, and the absorbances were less than 0.002, this indicates that the tested excipients do not interfere.
Accuracy. For each active pharmaceutical ingredient two series of experiments were conducted. For nimesulide, in the first series ten working solutions with the concentration equal to 15 mg/L, and in the second series ten sample solutions from tablets with the concentration equal to 15 mg/L were prepared. For meloxicam, in the first series ten working solutions with the concentration equal to 10 mg/L, and in the second series ten sample solutions from tablets with the concentration equal to 15 mg/L were prepared. The absorbances of the solutions were recorded as described in the general procedure, the concentrations of the solutions were calculated according to the regression equations, and the relative uncertainties were determined. The results are collected in Table 4.
Intra-day precision. For each active pharmaceutical ingredient two series of experiments were conducted. For nimesulide, in the first series ten working solutions with the concentration equal to 15 mg/L, and in the second series ten sample solutions from tablets with the concentration equal to 15 mg/L were prepared. For meloxicam, in the first series ten working solutions with the concentration equal to 10 mg/L, and in the second series ten sample solutions from tablets with the concentration equal to 15 mg/L were prepared. The absorbances of the solutions were recorded as described in the general procedure, the concentrations of the solutions were calculated according to the regression equations, and the relative standard deviations were determined. The results are collected in Table 5.
Inter-day precision. The four series of solution were prepared as described in the previous section during five consecutive days. The absorbances of the solutions were recorded as described in the general procedure, the concentrations of the solutions were calculated according to the regression equations, and the relative standard deviations were determined. The results are collected in Table 5.
Accuracy for the determination of model swab extract solutions. For each active pharmaceutical ingredient two series of experiments were conducted. For nimesulide, in the first series ten swab extract solutions with the concentration equal to 15 mg/L, and in the second series ten swab extract solutions from tablets with the concentration equal to 15 mg/L were prepared. For meloxicam, in the first series ten swab extract solutions with the concentration equal to 10 mg/L, and in the second series ten swab extract solutions from tablets with the concentration equal to 15 mg/L were prepared. The absorbances of the solutions were recorded as described in the general procedure, the concentrations of the solutions were calculated according to the regression equations, and the relative uncertainties were determined. The results are collected in Table 4.
Precision for the determination of model swab extract solutions. For each active pharmaceutical ingredient two series of experiments were conducted. For nimesulide, in the first series five swab extract solutions with the concentration equal to 15 mg/L, and in the second series five swab extract solutions from tablets with the concentration equal to 15 mg/L were prepared. For meloxicam, in the first series five swab extract solutions with the concentration equal to 10 mg/L, and in the second series five swab extract solutions from tablets with the concentration equal to 15 mg/L were prepared. The absorbances of the solutions were recorded as described in the general procedure, the concentrations of the solutions were calculated according to the regression equations, and the relative standard deviations were determined. The results are collected in Table 5.

Discussion

The experiments show that the proposed spectrophotometric methods are suitable for the determination of nimesulide and meloxicam in industrial equipment cleaning validation samples. The methods are rapid and simple; they do not require complicated sample preparation or sophisticated equipment. The methods are selective with respect to the common excipients, sensitive (the molar attenuation coefficient equals 6100 m2/mol for nimesulide and 9100 m2/mol for meloxicam, the limit of detection equals 0.8 mg/L for nimesulide and 1.9 mg/L for meloxicam, and the limit of quantification equals 2.5 mg/L for nimesulide and 5.8 mg/L for meloxicam), accurate (the relative uncertainty for the analysis of pharmaceutical formulations does not exceed 1%, the relative uncertainty for the analysis of modelling swab extract does not exceed 4%, which is acceptable for cleaning validation sample analysis), and precise (the relative standard deviation does not exceed 3% for intra-, 4% for inter-day precision, and 5% for analysis of modelling swab extracts). The calibration graphs are linear in the range from 5 to 25 mg/L of of both nimesulide and meloxicam with the good correlation coefficient. The methods are recommended for the routine and quick analysis of nimesulide and meloxicam in industrial equipment cleaning validation samples.

Conclusions

Simple spectrophotometric methods for the determination of nimesulide and meloxicam in industrial equipment cleaning validation samples using sodium carbonate were proposed. The methods are based on the colourimetric determination of basic form of the drugs in alkaline medium. The methods show a good analytical performance, do not require lengthy sample preparation and sophisticated laboratory equipment and are suitable for the routine analysis.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Conflicts of Interest

The author was employed by LLC “Velpharm” during the period of time from February 2020 till May 2021.

References

  1. Noble, S.; Balfour, J. A. Meloxicam. Drugs 1996, 51(3), 424-430, Doi 10.2165/00003495-199651030-00007.
  2. Fleischmann, R.; Iqbal, I.; Slobodin, G. Meloxicam. Expert opinion on pharmacotherapy, 2002, 3(10), 1501-1512. Doi 10.1517/14656566.3.10.1501.
  3. Davis, R.; Brogden, R. N. Nimesulide. Drugs, 1994, 48(3), 431-454. Doi 10.2165/00003495-199448030-00008.
  4. Ward, A.; Brogden, R. N. Nimesulide. Drugs, 1988, 36(6), 732-753. Doi 10.2165/00003495-198836060-00004.
  5. Salade, D. A.; Arote, K. S.; Patil, P. H.; Patil, P. S.; Pawar, A. R. A Review on Pharmaceutical Cleaning Validation. Asian Journal of Pharmaceutical Analysis, 2022, 12(3), 197-202. Doi 10.52711/2231-5675.2022.00033.
  6. Sarwar, A.; McSweeney, C.; Smith, M.; Timmermans, J.; Moore, E. Investigation of an alternative approach for real-time cleaning verification in the pharmaceutical industry. Analyst, 2020, 145(22), 7429-7436. Doi 10.1039/D0AN01219J.
  7. Starek, M.; Krzek, J. A review of analytical techniques for determination of oxicams, nimesulide and nabumetone. Talanta, 2009, 77(3), 925-942. Doi 10.1016/j.talanta.2008.09.022.
  8. Mahale, N. B.; Badhan, P. J.; Nikam, K. R.; Chaudhari, S. R. Comparative in vitro evaluation of commercial Nimesulide tablets. International Journal of pharmaceutical sciences and research, 2011, 2(10), 2610-2612. Doi 10.13040/IJPSR.0975-8232.2(10).2610-12.
  9. da Fonseca, L. B.; Labastie, M.; de Sousa, V. P.; Volpato, N. M. Development and validation of a discriminative dissolution test for nimesulide suspensions. AAPS PharmSciTech, 2009, 10(4), 1145-1152. Doi 10.1208/s12249-009-9320-4.
  10. Singh, S.; Sharda, N.; & Mahajan, L. Spectrophotometric determination of pKa of nimesulide. International journal of pharmaceutics, 1999, 176(2), 261-264. Doi 10.1016/S0378-5173(98)00304-4.
  11. Nagaraja, P.; Yathirajan, H. S.; Arunkumar, H. R.; Vasantha, R. A. Novel coupling reagents for the sensitive spectrophotometric determination of nimesulide in pharmaceutical preparations. Journal of pharmaceutical and biomedical analysis, 2002, 29(1-2), 277-282. Doi 10.1016/S0731-7085(02)00060-2.
  12. Altinöz, S.; Dursun, Ö. Ö. Determination of nimesulide in pharmaceutical dosage forms by second order derivative UV spectrophotometry. Journal of pharmaceutical and biomedical analysis, 2000, 22(1), 175-182. Doi 10.1016/S0731-7085(99)00264-2.
  13. Florea, M.; Monciu, C. M.; Andritoiu, M. L.; Bacanu, L. G. Spectrophotometric determination of nimesulide through ion-pair complex formation with hexadecyltrimethylammonium bromide. Farmacia, 2008, 56(6), 639-646.
  14. Saber, A. L.; El-Sayed, G. O. Extractive spectrophotometric determination of anti-inflammatory drug nimesulide in pharmaceutical formulations and human plasma. Journal of Food and Drug Analysis, 2011, 19(4), 429-436. Doi 10.38212/2224-6614.2208.
  15. Lakshmi, C. S.; Reddy, M. N. Spectrophotometric estimation of nimesulide and its formulations. Microchimica Acta, 1999, 132(1), 1-6. Doi 10.1007/PL00010067.
  16. Perju, A. C.; Mândrescu, M.; Spac, A. F.; Dorneanu, V. Nimesulide spectrophotometric determination in the visible region. Revista Medico-chirurgicala a Societatii de Medici si Naturalisti din Iasi, 2007, 111(2), 535-539.
  17. Kamalapurkar, O.S.; Harikrishna ,Y. UV spectrophotometric estimation ofnimesulide. Eastern Pharmacist, 1997, 40(478), 145-146.
  18. Chen, X. Determination of nimesulide in suppositories by UV spectrometry.
  19. Zhongguo Xiandai Yingyong Yaoxue, 2007, 24(2), 151-153.
  20. Chandran, S.; Saggar, S.; Priya, K.P.; Saha, R.N. New ultraviolet spectrophotometric method for the estimation of nimesulide. Drug Development and Industrial Pharamacy, 2000, 26(2), 229-234. Doi 10.1081/DDC-100100350.
  21. Upadhyay, K.; Asthana, A.; Tiwari, N.; Mathew, S. B. Determination of nimesulide in pharmaceutical and biological samples by a spectrophotometric method assisted with the partial least square method. Research on Chemical Intermediates, 2013, 39(8), 3553-3563. Doi 10.1007/s11164-012-0862-9.
  22. Pino, K. F. D.; Oliveira, L. N.; Silva, M. J.; Caon-Filho, O.; Dadamos, T. R. L. Spectrophotometric Determination of Nimesulide, Tribulus terrestris, and Amoxicillin in an Alkaline Medium, in Clinical and Commercial Samples. Journal of Applied Spectroscopy, 2019, 85(6), 1151-1157. Doi 10.1007/s10812-019-00774-9.
  23. Chowdary, K. R.; Kumar, K. G.; & Rao, G. D. New spectrophotometric methods for the determination of nimesulide. Indian journal of pharmaceutical sciences, 1999, 61(2), 86-89.
  24. Bhatti, M. K.; Hayat, M. M.; Nasir, R.; Ashraf, M.; Hussain, B.; Ahmad, I. Development and validation of spectrophotometric method for the determination of nimesulide in bulk and tablet dosage forms by biuret reagent method. Journal of the Chemical Society of Pakistan, 2012, 34(3), 713-716.
  25. El-henawy, M. M. E; Ragab, G. H.; Amin, A. E. S.; Sultan A., F. Spectrophotometric determination of nimesulide in pure and in pharmaceutical formulations using ion-associate complex formation. Asian Journal of Pharmaceutical Analysis and Medicinal Chemistry, 2014, 2(4), 240-248.
  26. Nagaraja, P.; Arun Kumar, H. R.; Vasantha, R. A.; Yathirajan, H. S. Spectrophotometric determination of nimesulide by oxidative coupling with N-bromosuccinimide and promethazine hydrochloride. Oxidation communications, 2003, 26(1), 116-120.
  27. Mamatha, N.; Radhika, K.; Kumar, S. A. S. Sensitive and validated UV spectrophotometric methods for the estimation of nimesulide in pharmaceutical and bulk formulations. World Journal of Pharmaceutical Research, 2014, 3(3), 4241-4247.
  28. Reddy, M. N.; Reddy, K. S.; Shankar, D. G.; Sreedhar, K. Spectrophotometric determination of nimesulide. Indian journal of pharmaceutical sciences, 1998, 60(3), 172-173.
  29. Patil, S. V. Electroanalytical and UV- spectroscopic study for analysis of nimesulide in pharmaceutical samples. International Journal of Chemical Studies, 2022, 10(1), 7-12.
  30. Shakkor, S. J. Spectrophotometric Determination of Reduced Nimesulide using 8-Hydroxyquinolinol Reagent in Pharmaceutical Preparations. Kirkuk University Journal-Scientific Studies, 2015, 10(1), 143-157.
  31. Soni, M. K.; Sharma, K. An Eco-friendly spectrophotometric analysis of poorly water-soluble drug (Nimesulide) using the mixed hydrotropic concept. Asian Journal of Pharmaceutical and Health Sciences, 2020, 9(4), 2181-2184.
  32. Shrivastava, D.; Dwivedi, S. Estimation of nimesulide using mixed solvency approach. International Journal of Pharmacy & Life Sciences, 2020, 11(5), 6629-6634.
  33. Murthy, T. K.; Reddy, M. N.; Reddy, M. D.; Sankar, D. G. Spectrophotometric determination of flutamide, nimesulide and meloxicam. Asian Journal of Chemistry, 2001, 13(3), 915-918.
  34. Garcı́a, M. S.; Sánchez-Pedreño, C.; Albero, M. I.; Martı́, J. Spectrophotometric methods for determining meloxicam in pharmaceuticals using batch and flow-injection procedures. European journal of pharmaceutical sciences, 2000, 9(3), 311-316. Doi 10.1016/S0928-0987(99)00069-X.
  35. Oliveira, É. D. F. S.; Azevedo, R. D. C. P.; Bonfilio, R.; Oliveira, D. B. D.; Ribeiro, G. P.; Araújo, M. B. D. Dissolution test optimization for meloxicam in the tablet pharmaceutical form. Brazilian Journal of Pharmaceutical Sciences, 2009, 45(1), 67-73. Doi 10.1590/S1984-82502009000100008.
  36. Mandrescu, M.; Spac, A. F.; Dorneanu, V. Spectrophotometric determination of meloxicam. Revista de chimie, 2009, 60(2), 160-163.
  37. Hassan, E. M. Spectrophotometric and fluorimetric methods for the determination of meloxicam in dosage forms. Journal of pharmaceutical and biomedical analysis, 2002, 27(5), 771-777. Doi 10.1016/S0731-7085(01)00530-1.
  38. Al-Momani, I. F. Indirect flow-injection spectrophotometric determination of meloxicam, tenoxicam and piroxicam in pharmaceutical formulations. Analytical sciences, 2006, 22(12), 1611-1614. Doi 10.2116/analsci.22.1611.
  39. Alam, M. N.; Rahman, N.; Azmi, S. N. H. Optimized and validated spectrophotometric method for the determination of uranium (VI) via complexation with meloxicam. Journal of hazardous materials, 2008, 155(1-2), 261-268. Doi 10.1016/j.jhazmat.2007.11.055.
  40. Saha, R. K. Spectrophotometric micro determination of silver (I) using meloxicam as a new analytical reagent. Oriental Journal of chemistry, 2016, 32(1), 499-507. Doi 10.13005/ojc/320157.
  41. Taha, E. A.; Salama, N. N.; Abdel Fattah, L. S. Stability-indicating methods for determination of meloxicam and tenoxicam in the presence of their degradation products. Spectroscopy letters, 2002, 35(4), 501-516. Doi 10.1081/SL-120013886.
  42. Dhandapani, B.; Eswara, M. S.; Susrutha, N.; Rama, S.; Rani, S.; Sarath, T.; Celestin, R. Spectrophotometric estimation of meloxicam in bulk and its pharmaceutical formulations. International Journal of Pharma Sciences and Research, 1(4), 217-221.
  43. Gurupadayya, B. M.; Trinath, M. N.; Shilpa, K. Spectrophotometric determination of meloxicam by sodium nitroprusside and 1,10-phenanthroline reagents in bulk and its pharmaceutical formulation. Indian Journal of Chemical Technology, 2013, 20(2), 111-115.
  44. Reddy, M. N.; Murthy, T. K.; Rajita, K.; Shankar, D. G. New spectrophotometric methods for the determination of meloxicam. Indian Journal of Pharmaceutical Sciences, 2001, 63(3), 245-247.
  45. Joseph-Charles, J.; Bertucat, M. Determination of meloxicam in tablet formulations by ultraviolet spectrophotometry and high-performance liquid chromatography. Analytical letters, 1999, 32(10), 2051-2059. Doi 10.1080/00032719908542951.
  46. Abed, R. I.; Hadi, H. Determination of meloxicam using direct and indirect flow injection spectrophotometry. Current Pharmaceutical Analysis, 2021, 17(2), 254-264. Doi 10.2174/1573412916666200224103731.
  47. Zawilla, N. H.; Mohammad, M. A. A.; Aly, S. E. M. Determination of meloxicam in bulk and pharmaceutical formulations. Journal of pharmaceutical and biomedical analysis, 2003, 32(6), 1135-1144. Doi 10.1016/S0731-7085(03)00232-2.
  48. Nemutlu, E.; Sedef, K. I. R. Validated determination of meloxicam in tablets by using UV spectrophotometry. Hacettepe University Journal of The Faculty of Pharmacy, 2004, 24(1), 13-24.
  49. Vasiliki, V.; Pinto, P. C. A. G.; Saraiva, M. L. M. F. S.; Lima, J. L. F. C. Sequential injection determination of meloxicam in pharmaceutical formulations with spectrophotometric detection. Canadian Journal of Analytical Sciences and Spectroscopy, 2007, 52(6), 351-358.
  50. Hasan, S. H.; Othman, N. S.; Surchi, K. M. Development and Validation of a UV-Spectrophotometric Method for Determination of Meloxicam in Bulk and in Tablet Formulations. International Journal of Pharma Sciences and Research, 2015, 6(7), 1040-1045.
  51. Hasan, S. H.; Othman, N. S.; Surchi K., M. Spectrophotometric Method for Determination of Meloxicam in Pharmaceutical Formulations Using N-bromosuccinimide as an Oxidant. International Journal of Pharma Sciences and Research, 2014, 5(12), 963-969.
  52. Induri, M.; Mantripragada, B. R.; Yejella, R. P.; Kunda, P. R.; Nannapaneni, D. T.; Boddu, R. Dissolution studies and quantification of meloxicam in tablet dosage form by spectrophotometry. Pakistan journal of pharmaceutical sciences, 2012, 25(1), 283-287.
  53. Elham, A. Simple Spectrophotometric Methods for the Determination of Meloxicam in Presence of Its Degradation Products. Chinese Journal of Pharmaceutical Analysis, 2004, 24(4), 390-394.
  54. Mahood, A. M.; Najm, N. H. Spectrophotometric Estamation of Meloxicam Using Charge Transfer Complex. In: IOP Conference Series: Materials Science and Engineering. Bristol: IOP Publishing, 2019, Vol. 571, No 1, Paper No 012081. Doi 10.1088/1757-899X/571/1/012081.
  55. Kasem, M. A.; Megahed, H. E.; Moustafa, M. E.; Ibrahim, H. A. Sensitive, Direct and Rapid Spectrophotometric Method for the Determination of Meloxicam through Ion-Associate Complex Formation. Journal of Basic and Environmental Sciences, 2014, 1, 92–101. [Google Scholar]
  56. Sundarapandian, M.; Venkataraman, S.; Xavierarulappa, R.; Boopathi, M.; Selvakumar, S. Spectrophotometric Determination of Meloxicam in Bulk Drug and Pharmacuetical Formulations. Asian Journal of Research in Chemistry, 2009, 2(4), 467-468.
  57. Pomykalski, A.; Hopkała, H. Comparison of classic and derivative UV spectrophotometric methods for quantification of meloxicam and mefenamic acid in pharmaceutical preparations. Acta poloniae pharmaceutica, 2011, 68(3), 317-323.
  58. Taha, E. A.; Salama, N. N.; Fattah, L. E. S. A. Spectrofluorimetric and spectrophotometric stability-indicating methods for determination of some oxicams using 7-chloro-4-nitrobenz-2-oxa-1,3-diazole (NBD-Cl). Chemical and pharmaceutical bulletin, 2006, 54(5), 653-658. Doi 10.1248/cpb.54.653.
  59. Chaudhary, K. B.; Bhardwaj, K.; Verma, G.; Kumar, P. Validated Analytical Method development for the determination of Meloxicam by UV Spectroscopy in API and Pharmaceutical dosage form. Asian Journal of Pharmaceutical Education and Research, 2018, 7(2), 60-69.
  60. Baban, S. O.; Jallal, A. F. Determination of meloxicam in pharmaceutical formulation by azo-coupling reaction with sulphanilic acid using both batch and flow-injection technique. Rafidain Journal of Science, 2011, 22(4), 121-132.
  61. Redasani, V. K.; Patel, C. F.; Chhajed, C. F.; Surana, S. S. Quantitative Determination of Meloxicam in bulk and in tablet by UV Spectrophotometry. International Journal of Pharmaceutics and Drug Analysis, 2014, 2(3), 246-250.
  62. Abbas, R. F.; Mahdi, N. I.; Waheb, A. A.; Aliwi, A. G.; Falih, M. S. Fourth Derivative and Compensated Area under the Curve Spectrophotometric Methods Used for Analysis Meloxicam in the Local Market Tablet. Al-Mustansiriyah Journal of Science, 2018, 29(3), 70-76.
  63. Chaplenko, A. A.; Monogarova, O. V.; Oskolok, K. V. Spectroscopic and colorimetric determination of meloxicam, lornoxicam, tenoxicam in drugs. International Journal of Pharmaceutical & Biological Archives, 2018, 9(1), 31-35.
  64. Kuchekar, B. S.; Late, S. G.; Shingavi, A. A.; Shinde, D. B. Spectrophotometric Estimation Of Melatonin And Meloxicam Using Folin-Ciocalteu Reagent. Indian Journal of Pharmaceutical Sciences, 2001, 63(4), 321-323.
  65. Adrian, R. Research concerning the probabilities of the errors which happen in making observations, etc. The Analyst; or Mathematical Museum, 1808, 1(4), 93-109.
  66. Ringbom, A. Über die Genauigkeit der colorimetrischen Analysenmethoden I. Zeitschrift für analytische Chemie, 1938, 115(9), 332-343. Doi 10.1007/BF01753937.
  67. Ayres, G. H. Evaluation of accuracy in photometric analysis. Analytical Chemistry, 1949, 21(6), 652-657. Doi 10.1021/ac60030a002.
  68. Youmans, H. L.; Brown, V. H. Selection of optimum ranges for photometric analysis. Analytical Chemistry, 1976, 48(8), 1152-1155. Doi 10.1021/ac50002a022.
  69. Sandell, E. B. Colorimetric Determination of Traces of Metals. New York: Interscience Publishers, 1944.
  70. Currie, L. A. Detection and quantification limits: origins and historical overview. Analytica Chimica Acta, 1999, 391(2), 127-134. Doi 10.1016/S0003-2670(99)00105-1.
  71. Shrivastava, A.; Gupta, V. B. Methods for the determination of limit of detection and limit of quantitation of the analytical methods. Chronicles of young scientists, 2011, 2(1), 21-25. Doi 10.4103/2229-5186.79345.
  72. Little, T. A. Method Validation Essentials, Limit of Blank, Limit of Detection, and Limit of Quantitation. BioPharm International, 2015, 28(4), 48-51.
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Figure 1. The absorption spectrum of 25 mg/L solution of nimesulide against 10% solution of sodium carbonate.
Figure 1. The absorption spectrum of 25 mg/L solution of nimesulide against 10% solution of sodium carbonate.
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Figure 2. The absorption spectrum of 20 mg/L solution of meloxicam against 10% solution of sodium carbonate.
Figure 2. The absorption spectrum of 20 mg/L solution of meloxicam against 10% solution of sodium carbonate.
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Figure 3. Dependence of the absorbances of nimesulide and meloxicam on the solvent concentration.
Figure 3. Dependence of the absorbances of nimesulide and meloxicam on the solvent concentration.
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Figure 4. The calibration graphs for nimesulide and meloxicam.
Figure 4. The calibration graphs for nimesulide and meloxicam.
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Table 1. A review of spectrophotometric methods of determination of nimesulide.
Table 1. A review of spectrophotometric methods of determination of nimesulide.
Solvent Used reagents Wavelength, nm Linearity, mg/L Accuracy, % Precision, % Reference
Methanol None 397 Not specified Not specified Not specified [8]
Water NaOH 397 5-30 2 1 [9]
Water Phosphate buffer 393 Not specified Not specified Not specified [10]
Methanol Iminodibenzyl 600 0.1-7.5 0.2 0.1 [11]
Methanol 3-aminophenol 470 0.4-12 0.3 0.2 [11]
Ethanol None 262-291WXCSecond derivative 2-90 2 1 [12]
Chloroform None 248-268WXCSecond derivative 2-50 3 1 [12]
Water/chloroform Hexadecyl-trimethyl-ammonium bromide 404 6-20 1 0.7 [13]
Water/chloroform Bromocresol green 412 2-18 5 0.6 [14]
Water/chloroform Bromocresol purple 410 2-16 4 0.5 [14]
Water/chloroform Bromothymol blue 407 2-18 3 0.5 [14]
Water/chloroform Brilliant blue G 502 2-18 5 0.5 [14]
Water/chloroform Methyl orange 482 2-14 3 0.7 [14]
Water p-N,N-dimethyl phenylene diamine dihydrochloride, chloramine-T 540 10-50 0.8 0.6 [15]
Water p-N,N-dimethyl phenylene diamine dihydrochloride, 3-methyl-2-benzothiazolinone hydrazine hydrochloride 600 12.5-75 1.2 0.4 [15]
Water HNO2, cresyl fast violet acetate 565 2-12 2.2 0.2 [15]
Water p-methyl aminophenol sulphate, K2Cr2O7 550 20-120 0.8 0.5 [15]
Water Thymol 476 5-40 2.4 2.2 [16]
Water NaOH 397 Not specified Not specified Not specified [17]
Water NaOH 397 Not specified Not specified Not specified [18]
Water/aceto-nitrile None 300 10-50 1 0.4 [19]
Acetonitrile None 300 10-50 0.4 0.4 [19]
Methanol Orcinol 465 0.4-4 1.8 1.6 [20]
Water NaOH 460 0.4-5.1 8 Not specified [21]
Methanol/water Phloroglucinol, ammonium sulfamate 400 4-20 2 Not specified [22]
Methanol/water p-dimethylamino benzaldehyde 415 4-24 2 Not specified [22]
Methanol CuSO4, KNaC4H4O6, KI, NaOH 400 25-200 0.8 2.1 [23]
Ethanol/water Bromocresol green 643 2-14 0.5 1.2 [24]
Ethanol/water Bromocresol purple 437 2-12 0.5 1.6 [24]
Ethanol/water Brilliant blue G 554 2-13 1 1.3 [24]
Methanol/water N-bromo-succinimide, promethazine hydrochloride 610 0.4-8 Not specified Not specified [25]
Methanol None 297 10-50 2 Not specified [26]
Methanol/aceto-nitrile None 295 10-50 2 Not specified [26]
Methanol Folin–Ciocalteu reagent 600 Not specified Not specified Not specified [27]
Water NaOH 393 1.5-14 Not specified Not specified [28]
Methanol/water 8-hydroxy-quinolinol 480 0.5-25 1.6 1.2 [29]
Water Sodium citrate, phenol 390 10-40 3.6 Not specified [30]
Water Sodium benzoate, phenol 390 10-50 1.5 Not specified [31]
Water KMnO4, Fast green FCF 625 Not specified Not specified Not specified [32]
Water Na2CO3 397 This work
Table 2. A review of spectrophotometric methods of determination of meloxicam.
Table 2. A review of spectrophotometric methods of determination of meloxicam.
Solvent Used reagents Wavelength, nm Linearity, mg/L Accuracy, % Precision, % Reference
Water KMnO4, Fast green FCF 625 Not specified Not specified Not specified [32]
Methanol FeCl3 570 2-200 2.3 Not specified [33]
Water NaOH 362 0.5-20 1.9 Not specified [33]
Water Phosphate buffer 362 Not specified Not specified Not specified [34]
Methanol/aceto-nitrile AlCl3 375 5-30 2.7 1.8 [35]
Ethanol HCl, NaOH 340-384WXCDifference spectrum 2-10 0.5 0.8 [36]
Ethanol HCl 322-368WXCFirst derivative 1-10 0.5 1.3 [36]
HCl 343-385WXCSecond derivative 1-10 0.5 0.6 [36]
Water/chloroform Saframin T 518 4-12 1 0.4 [36]
Water N-bromo-succinimide, chloranilic acid 530 10-160 8 1.2 [37]
Water/1,4-dioxan UO2(NO3)2 398 5-60 1 1.5 [38]
Water/ethanol AgNO3 412 1-15 Not specified 1.3 [39]
Methanol/water 3-Methyl-2-benzothiazolinone-hydrazone hydrochloride, ceric ammonium sulphate 450 2-20 1.0 0.5 [40]
Water NaOH 269 5-30 0.3 4.2 [41]
Water FeCl3 476 50-250 0.5 2 [41]
Water Trisodium citrate 269 5-30 2.3 5.7 [41]
Water Sodium nitroprusside, hydroxylamine 363 4-20 3.8 1.5 [42]
Methanol/water FeCl3, 1,10-phen-anthroline 343 10-50 1.5 0.9 [42]
Water FeCl3, K3[Fe(CN)6] 770 0.25-2.5 1.2 Not specified [43]
Water Folin–Ciocalteu reagent 740 5-15 0.4 Not specified [43]
Water/1,4-dioxan/acetonitrile HCl 341 6-14 2.3 1.8 [44]
Water Procaine benzylpenicillin 492 5-80 Not specified Not specified [45]
Water p-methyl aminophenol sulfate, NaIO4 656 15-225 Not specified Not specified [45]
Methanol/water/ chloroform Methylene blue 654 1-5 1.2 2.3 [46]
Acetonitrile 2,3-dichloro-5,6-WXCdicyano-p-benzoquinone 455 40-160 1 1 [46]
Methanol/water Borate buffer 363 0.5-30 1 1.4 [47]
Water FeCl3, K3[Fe(CN)6] 770 10-25 5 Not specified [48]
Methanol/water HCl 346 5-150 3 0.5 [49]
Water N-bromo-succinimide, indigocarmine 610 0.2-50 1.5 Not specified [50]
Methanol/water NaOH 365 2-12 1.1 1.3 [51]
Water Phosphate buffer 360 2-12 1.6 1.1 [51]
Methanol UO2CO3 406 10-100 1 Not specified [52]
Methanol FeCl3 580 37.5-300 1 Not specified [52]
Ethanol FeCl3, K3[Fe(CN)6] 708 0.1-11 1.3 0.7 [53]
Water Orange G 358 1-22 0.4 0.2 [54]
Water Methylene blue 652 1-22 0.2 0.2 [54]
Water CuCl2 361 1-22 0.2 0.2 [54]
Water/chloroform Bromocresol green 415 10-50 0.8 Not specified [55]
Water NaOH 361 4-14 1.2 Not specified [56]
Water NaOH 270 4-14 4.2 Not specified [56]
Water NaOH 215 4-14 5.5 Not specified [56]
Water NaOH 386WXCFirst derivative 4-14 1.3 Not specified [56]
Water NaOH 340WXCFirst derivative 4-14 1.5 Not specified [56]
Water NaOH 273WXCFirst derivative 4-14 3.4 Not specified [56]
Water NaOH 257WXCFirst derivative 4-14 4 Not specified [56]
Water NaOH 409WXCSecond derivative 4-14 1.5 Not specified [56]
Water NaOH 359WXCSecond derivative 4-14 1.4 Not specified [56]
Water NaOH 316WXCSecond derivative 4-14 3.7 Not specified [56]
Water NaOH 278WXCSecond derivative 4-14 2.4 Not specified [56]
Water NaOH 269WXCSecond derivative 4-14 1.4 Not specified [56]
Water NaOH 251WXCSecond derivative 4-14 2.2 Not specified [56]
Water/acetone 7-chloro-4-nitrobenz-2-oxa-1, 3-diazole 460 0.5-4 1.7 1.3 [57]
Ethanol None 365 2-18 2.3 1.3 [58]
Water NaNO2, HCl, sulphanilic acid 365 1-20 3.5 2.3 [59]
Water NaOH 269 5-30 1.6 1.4 [60]
Water NaOH 253-279WXCArea under curve 5-30 1.4 1.2 [60]
Water NaOH 275WXCFirst derivative 50-300 1.5 1.6 [60]
Water NaOH 361WXCFourth derivative 5-35 0.6 3.4 [61]
Water NaOH 264-277, WXC352-378WXCArea under curve 5-35 0.7 1.8 [61]
Water/methanol 7-chloro-4-nitrobenz-2-oxa-1, 3-diazole 461 0.5-5 5 4 [62]
Water Folin-Ciocalteu reagent, Na2CO3 700 1.5-22.5 1.4 Not specified [63]
Water Na2CO3 362 This work
Table 3. The parameters of the linear regression of the dependences of the absorbances of the solutions of nimesulide at 397 nm and meloxicam at 362 nm on the drug concentrations, and the analytical parameters of the methods.
Table 3. The parameters of the linear regression of the dependences of the absorbances of the solutions of nimesulide at 397 nm and meloxicam at 362 nm on the drug concentrations, and the analytical parameters of the methods.
Parameter Value
Analysed pharmaceutical ingredient Nimesulide Meloxicam
Wavelength of maximum absorbance (nm) 397 362
Slope and its confidence interval (f = 4, p = 95%) (L/mg) 0.051 ± 0,001 0.038 ± 0,001
Intercept and its confidence interval (f = 4, p = 95%) –0.002 ± 0,001 –0.01 ± 0,01
R2 value 0.999 0.996
Linearity range (mg/L) 5 – 25 5 – 25
Ringbom’s optimum range (mg/L) 4 – 14 6 – 18
Molar attenuation coefficient and its confidence interval (f = 4, p = 95%) (m2/mol) 6100 ± 100 9100 ± 300
Sandell’s sensitivity coefficient and its confidence interval (f = 4, p = 95%) (μg/cm2) 0.019 ± 0.002 0.026 ± 0.004
Limit of detection (mg/L) 0.8 1.9
Limit of quantification (mg/L) 2.5 5.8
Table 4. The accuracy tests of the methods and for the model swab extract solutions.
Table 4. The accuracy tests of the methods and for the model swab extract solutions.
Tested solutions of nimesulide Mean measured concentration of nimesulide (mg/L) Relative uncertainty (%) Tested solutions of meloxicam Mean measured concentration of meloxicam (mg/L) Relative uncertainty (%)
Working solution, 15 mg/L 15.08 0.5 Working solution, 10 mg/L 10.06 0.6
Sample solution from tablets, 10 mg/L 9.95 0.5 Sample solution from tablets, 15 mg/L 15.11 0.8
Swab extract from working solution, 15 mg/L 14.64 2.4 Swab extract from working solution, 10 mg/L 9.68 3.2
Swab extract from sample solution from tablets, 10 mg/L 9.71 2.9 Swab extract from sample solution from tablets, 15 mg/L 14.42 3.2
Table 5. The precision test of the method and for the model swab extract solutions.
Table 5. The precision test of the method and for the model swab extract solutions.
Tested solutions of nimesulide Standard deviation (mg/L) Relative standard deviation (%) Tested solutions of meloxicam Standard deviation (mg/L) Relative standard deviation (%)
Working solution, 15 mg/L (intra-day) 0.211 1.4 Working solution, 10 mg/L (intra-day) 0.131 1.3
Sample solution from tablets, 10 mg/L (intra-day) 0.229 2.3 Sample solution from tablets, 15 mg/L (intra-day) 0.393 2.6
Working solution, 15 mg/L (inter-day) 0.318 2.1 Working solution, 10 mg/L (inter-day) 0.244 2.4
Sample solution from tablets, 10 mg/L (inter-day) 0.312 3.2 Sample solution from tablets, 15 mg/L (inter-day) 0.439 3.0
Swab extract from working solution, 15 mg/L 0.542 3.7 Swab extract from working solution, 10 mg/L 0.329 3.4
Swab extract from sample solution from tablets, 10 mg/L 0.427 4.4 Swab extract from sample solution from tablets, 15 mg/L 0.591 4.1
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