Estudo de um derivado quinoxalínico do ácido ascórbico na síntese de nanopartículas de prata com potencial aplicação na detecção de L-cisteína

• Autor(a) principal: Pinheiro, Nayara de Araújo
• Data de Publicação: 2017
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/38255
• topic: Nanopartículas; Quimiossensor; Quinoxalina; L-cisteína; Nanoparticles; Quinoxaline; Chemosensor; L-cysteine

The synthesis of silver nanoparticles (AgNPs) has shown to be very relevant and promising due the outstanding properties of these materials, which made possible applications in the biological and technological areas. This work describes the synthesis of AgNPs based on the reduction and stabilizing abilities of the quinoxaline derivative of L-ascorbic acid, N-(2-aminophenyl)-3-((1S,2S)-1,2,3-trihydroxypropyl)-quinoxaline-2-carboxamide (AAQX). AgNPs were characterized by means of naked-eye colorimetric analysis and UV-Vis spectroscopy. The results show that the optimum experimental condition for the synthesis of AgNPs was based on the 1:8 Ag+ - AAQX ratio, due the smallest change in the LSPR band over the days. It has been proposed a mechanism of formation of AgNPs in which the AAQX probably binds to the metallic atoms by the Oxygen or Nitrogen atoms present in its composition. A preliminary study employing the herein synthesized AgNPs in the detection of L-cysteine (Cys) was carried out. A possible selectivity for Cys against other amino acids was verified. The influence of the Cys concentration and time of analysis were verified by UV-Vis spectroscopy. The preliminary results herein reported can foster the development of new chemosensoers for Cys as well as for other analytes, which is very relevant for chemistry and well as biological and technological fields.