Measurement of enzymatic activity using gold nanoparticles in open tube capillary electrophoresis.

EMILIANO FELICI; CHIEN C. WANG,; MARÍA R. GOMEZ,; PATRICIA W. STEGE.

Cartagena

Simposio; 21st Latin American Symposium on Biotechnology, Biomedical, Biopharmaceutical and Industrial Applications of Capillary Electrophoresis and Microchip Technology; 2015

Nanostructuredmaterials have great interest in the scientific-technological field due totheir physical properties. Metal based nanoparticles, especially goldnanoparticles (AuNPs) have excellent biocompatibility with different biologicalmolecules. Our particular interest in this type of nanoparticles relies on thepossibility of modifying their surfaces with the aim of acting as support ofdifferent macromolecules bringing stability to the system.The aim of this work was the immobilization of glutathionereductase-AuNPs bionanoconjugated to the inner phase of the 50 μmi.d.and 15 cm total lenght capillary using layer by layer polymeric network inthe inlet side.AuNPs were synthesized by reduction with sodium citrate addedunder stirring with excess of NaBH4. The AuNPs were purified and the solutionobtained was characterized by UV-VIS spectrophotometry and capillaryelectrophoresis. Bionanoconjugated nanoparticles were attached in the innerwall of capillaries using dimethylsiloxane as polymeric agent.Layer-by-Layer (LbL) deposition was developed by immersion procedure ofthe inlet side of the capillary. The immobilized bionanoconjugate wascharacterized by scanning electron microscope (SEM) to contact anglemeasurement observing morphological features designed biosensor.AuNPs have the advantage of being stable, having low production cost andhigh biocompatibility acting as support and stabilizing biological moleculesincreasing enzyme activity. In addition, the matrix used in the immobilizationprocess provides a biocompatible environment which allows the enzyme remainactive after the immobilization and improving the sensitivity of the biosensor.