Nanoparticle-assisted polymerase chain reaction (nanoPCR) is a novel method for rapid detection of pathogens. A sensitive and specific multiple nanoPCR assay was developed for simultaneous detection of three subgroups avian leucosis virus (ALV). In this study, three pairs of primers that were designed based on gp85 gene sequences of subgroup A, B and J, optimizations were carried out for better performance of the nanoPCR assay and remarkably improved the detection limit of the assay. The detection limit of the assay was 101copies/μl, which was 100-fold more sensitive than conventional PCR assays. The nanoPCR assay amplified the specific 336 bp, 625 bp and 167 bp fragments of ALV-A, -B and –J respectively and no cross-reactivity were found with the genomic DNA or cDNA of Newcastle disease virus, avian infectious laryngotracheitis virus, Marek's disease virus, infectious bronchitis vaccine, infectious bursal disease virus and avian encephalomyelitis Virus. To evaluate the detection ability of the assay, 186 clinical samples were detected by nanoPCR and the detection results were further confirmed by sequencing. The sequencing results were 100% in coincidence with the nanoPCR detection results, suggesting the possibility of clinical application of the newly developed nanoPCR assay. Taking all the results together, a highly specific and sensitive nanoPCR was successfully developed, which could be useful for rapid diagnosis of ALV in poultry farming.

A general method is presented that permits enantiomers, originally present in a low enantiomeric excess (%ee1), to accumulate in a high %ee (%ee2) without a chiral source present. An equation was derived that demonstrates the final %ee2 of any unreacted chiral starting material will become higher when that starting material has reacted to generate an additional chiral center, hence forming two sets of diastereomeric enantiomeric products. Importantly, chiral amplification factor (multiples), %ee2/%ee1, depends on the yield of this reaction (p), which exhibits a nonlinear increase in amplification as p approaches 100%. This process is inevitable. It represents a possible route by which small initial %ee1 values of prebiotic molecules could have been raised to high %ee2 contents during the pre-evolution of life period on Earth, without the need for an added chiral source to be present. This predicted behavior was then experimentally verified in Pictet-Spengler reactions of L-tryptophane methyl ester (L-TME) samples present in low enantiomeric excess (%ee1) with biacetyl or oxaldehyde (model reactions) run to various yields. Each reaction generates stereoisomer products, and chiral amplification of the L-TME’s initial %ee1 values to higher %ee2 values occurs in the unreacted (recovered) L-TME. Repeated cycles of these reactions create very high L-TME %ee values. Self-cyclodimerization of low %ee1 L-amino acids with their D-enantiomers to generate L,L-, D,D- and L,D-cyclic products were computationally studied, leading to the same conclusion. Small %ee1 values are enhanced to larger %ee2 in the unreacted starting materials.