RESUMO
Three novel metal squaric acid-peptide complexes, SQI-SQIII were prepared by addition of indium triflate or zinc chloride to the previously reported compounds [1], 3-(hydroxymethylamino)-4-(l-isoleucine methyl ester)-3-cyclobutene-1,2-dione (squarate 1), and 3-(hydroxymethylamino)-2-(l-isoleucine methyl ester)-4-thioxo-2-cyclobuten-1-one (squarate 2). The structures of SQI-SQIII were elucidated using NMR analysis. The electrochemical applications of two of these metal-squaric acid systems (SQI and SQII) were also investigated. Incorporation of SQII as a mediator, in the previously optimized Pt/p(HEMA)/p(pyrrole)/GOx electrode using the ionic liquid [bmim][BF(4)] as the solvent medium, produced a biosensor with enhanced properties, namely a sensitivity of 175.9mA/M d-glucose, working potential of +200mV, large linear range (0-12mM) and a detection limit of 1x10(-6)M.
Assuntos
Aminoácidos/química , Técnicas Biossensoriais/métodos , Ciclobutanos/química , Glucose/análise , Índio/química , Zinco/química , Aminoácidos/síntese química , Sítios de Ligação , Ciclobutanos/síntese química , Limite de Detecção , Espectroscopia de Ressonância Magnética , Peptídeos/síntese química , Peptídeos/químicaRESUMO
Extracts of eight medicinal plants from the Callejon de Huaylas in Peru were screened for antibacterial activity in eighteen bacterial strains by the agar-diffusion method; six of these were active against a variety of bacteria.