Nanomaterials' strong electrical and magnetic conductivity, as well as their large surface area, make them useful for resolving lower detection limit problems in monitoring applications. The use of nanoparticles (NPs) offered a new strategy for creating inexpensive and portable PFAS detection devices [
56]. Nanomaterials, including the luminescent brilliance of silver and gold nanoparticles, the metallic prowess of metal nanoparticles (MNPs), and the quantum wonders of quantum dots (QDs), assume a pivotal role in elevating the performance of biosensors to new heights. An uncomplicated sensor for detecting PFOA was developed. Early efforts to modify AuNPs involved utilizing thiol-terminated polystyrene. Upon introduction to the solution of AuNPs, the PFOA demonstrated a proclivity for aggregation, guided by the captivating dance of fluorine-fluorine interactions. The test performed admirably, with a noticeable shift in color from red to purple corresponding to increasing PFOA concentrations [
56]. A study documented the assessment of PFCs using a probe based on Au-NPs [
57]. This innovative approach employs a fusion of polyethylene glycol-terminated (PEG-thiols) and perfluoroalkyl-terminated (F-thiols) alkanethiol to intricately modify gold particles, sculpting them into a bespoke probeIn a mere half-hour temporal embrace, the ingeniously crafted probe unfurls its prowess, discerning the presence of PFCs within concentrations ranging from 0.1 to 1000 μg/L. This enhanced sensor manifests remarkable stability, boasting a detection limit finely tuned to 10 μg/L. Rigorous assessments conducted by the author within the realms of municipal and river water unveiled a sensor adorned with high selectivity specifically tailored for PFOA and PFOS [
58]. In the eloquent narrative penned by a study, a groundbreaking chapter unfolded introducing upconversion nanoparticles (UCNPs) as the luminescent protagonists in the sensor saga, meticulously crafted for the detection of PFOS [
59]. The genesis of these UCNPs took shape through the meticulous artistry of solvothermal synthesis. The synthesis and deposition of covalent organic framework (COF) on the surface of UCNPs occurred simultaneously. Increased selectivity and sensitivity for PFOS were noted in the synthesized UCNPs-COFs. In the unveiling of a sophisticated sensing platform, its application to scrutinize authentic water samples unfolds as a narrative of triumph, showcasing recoveries within the captivating range of 106% to 108% and an exquisite detection limit of 0.000075 ng/L for perfluorooctane sulfonate (PFOS). Embarking on a quest for a streamlined PFOS detection sensor, a research introduces a tale interwoven with titanium dioxide nanotubes (TiO
2-NTAs) [
60]. Within this sensor realm, acrylamide, ethylene glycol dimethacrylate, and 2,2-azobis(2-methylpropionitrile) emerge as the protagonists, respectively donning the roles of functional monomers, cross-linker, and initiator agent in the polymerization imprinting process. The resulting sensor emerges as a testament to both selectivity and sensitivity towards PFOS, boasting a discerning limit of detection at 86 µg/L and a linear range spanning from 250 to 5001 µg/L. Results from using the technique on environmental samples were positive. In order to detect PFOA in environmental samples, another study created a QDs sensor [
41]. Embarking on a scientific odyssey, CdTe@CdS-QDs materialized through the alchemical artistry of the sol-gel technique. The saga continued with the creation of silica films, meticulously imprinted at the molecular level onto CdTe@CdS-QDs. Aqueous ammonia, akin to a catalyst in this intricate ballet, presided over the proceedings. The narrative of creation unfolded with a polymerization technique, where 3-aminopropyltriethoxysilane donned the mantle of the functional monomer, and tetraethoxysilane stood as the cross-linker, weaving the intricate tapestry of molecular imprinting. The method demonstrated effectiveness, yielding a detection limit of 10.35 µg/L and a linear range spanning from 104 to 6211 µg/L [
61]. Values of recoveries seen by the author varied between 91 and 107%, with a relative standard deviation of 5.6%. PFOA in water was detected using the designed sensor with high selectivity. Research by S. Chen and colleagues in 2015, a luminescent symphony unfolded as they meticulously crafted a luminophore imprinting polymer, adorning the ultrathin nanosheets of carbon nitride (utg-C
3N
4) through the ballet of an electropolymerization technique [
52]. The resulting sensor, a testament to their precision, revealed a harmonious linearity extending across detection ranges from 20 to 40,000 ng/L. Finding a limit of detection of 10 ng/L was a significant achievement. Also, the sensor was used to the examination of water samples, with satisfactory recoveries (96%-103.8%) being attained. There was also significant concordance between HPLC-MS/MS and the findings.
In their scholarly endeavour to unveil the fingerprint of PFOS within biological samples, a study conceptualized a sensor ingeniously fashioned with the radiance of carbon quantum dots (CQD) [
56]. The integration of CQD with a chitosan hydrogel was orchestrated through the methodical process of electrochemical polymerization, culminating in the formation of a durable covalent bond. The interaction between sulfonates from chitosan and QDS, and amino groups from PFOS through electrostatic repulsion, forms a compound. This novel approach demonstrates sensitivity in detecting various perfluorinated compounds, including PFOA, PFOS, PFBS, and perfluorooctanoic acid. The highest imprinting factor discovered by the author was 2.75. The concentrations that could be added up to 1 ng/L were only as low as 0.00002 ng/L. The designed sensor yielded satisfactory recoveries (81-98%). Using a water-soluble CdS-QDS, another study created a straightforward and quick fluorometric method for measuring PFOA [
50]. The birth of radiant CdS-QDs, aglow with intense luminosity, unfolded through the transformative touch of 3-mercaptopropionic acid (MPA). In a dance of molecular interplay, the entrance of PFOA became the catalyst for an enchanting aggregation of MPA-CdS QDs, orchestrated by the alluring forces of fluorine-fluorine interaction. This mystical collaboration cast a spell, conjuring forth an augmented fluorescence emanating from the embrace of MPA-CdS QDs. The saga of detection unfolded with a determined linearity stretching from 207.03 µg/L to 16.56 mg/L, revealing its secrets with a calculated limit of detection at 124.2 µg/L.