Título: Luminescent monitoring of antibiotics based on the joint use of aptamers and metal nanoclusters.
Resumen: The study of the analytical potential of the synthesis of metal nanoclusters (NCs) has been carried out using oligonucleotides as interaction ligands in the development of fast-response luminescent systems to evaluate their potential use as analytical tools in the determination of antibiotics. NCs are structures composed of dozens of atoms of metallic nature where a stabilizing agent is needed for its reducing capacity to initiate the reduction process of metal ions and moderating the nucleation of the metallic structure. In this case, a single-stranded DNA oligonucleotide sequence was chosen as stabilizing agent to obtain silver nanoclusters (OLG-AgNCs). The oligonucleotide sequence is composed by the sequence necessary to obtain NCs linked to a sequence that acts as an aptamer against kanamycin. Furthermore, the combined use with split aptamers, splitting the oligonucleotides sequence needed for the aptamer in two parts, has led to a new research approach useful in developing biosensors for xenobiotic compounds in aquaculture. In this research, a fluorescent tunable biosensor was constructed by tethering a nanocluster beacon (NCB) pair composed of OLG-AgNCs and a G-rich enhancer sequence (GRS) at each end of both split aptamers. The NCB led to a fluorescence enhancement of the OLG-AgNCs because of their proximity to GRS, which is caused by the binding of both split aptamers when kanamycin is present. The study has successfully optimized the physicochemical and instrumental variables that influence the performance of the luminescent OLG-AgNCs complex formation and the aptameric reaction with kanamycin. By comparing the use of split aptamers with the complete aptamer and other procedures, the study has demonstrated the superiority of split aptamers and GRS regarding analytical features and incubation time. The practical application of the biosensor in determining kanamycin in aquaculture samples further underscores its specificity and reliability, making it a promising tool for the industry.
Congreso: XI NyNA 2024: International Congress on Analytical Nanoscience and Nanotechnology. September, 3-6 2024. Santiago de Compostela (Spain)
