Conjugated polymers nanostructured as smart interfaces for controlling the catalytic properties of enzymes

Author(s)

Barbosa, Camila Gouveia ^[1] ; Caseli, Luciano ^[1] ; Peres, Laura Oliveira ^[1]

Affiliation

^[1] Univ Fed Sao Paulo, Lab Hybrid Mat, Diadema, SP - Brazil

• Document type: Journal article
• Source: Journal of Colloid and Interface Science; v. 476, p. 206-213, AUG 15 2016.
• Web of Science Citations: 12

Abstract

The search for new molecular architectures to improve the efficiency of enzymes entrapped in ultrathin films is useful to enhance the effectiveness of biosensors. In this present work, conjugated polymers, based on thiophene and fluorine, were investigated to verify their suitability as matrices for the immobilization of urease. The copolymer poly{[}(9,9-dioctylfluorene)-co-thiophene], PDOF-co-Th was spread on the air-water interface forming stable Langmuir monolayers as determined by surface pressure-area isotherms, polarization-modulation reflection-absorption infrared spectroscopy (PM-IRRAS), and Brewster angle microscopy (BAM). Urease was incorporated in the floating monolayers being further transferred to solid supports as mixed Langmuir-Blodgett (LB) films. These films were then characterized with transfer ratio, fluorescence spectroscopy, PM-IRRAS and atomic force microscopy, confirming the co-transfer of the enzyme as well as its structuring in beta-sheets. The catalytic activity was detected for urease, with a lower reaction rate than that encountered for the homogeneous environment. This was attributed to conformational constraints imposed to the biomacromolecule entrapped in the polymeric matrix. (C) 2016 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 15/23446-0 - Smart surfaces: nanostructured and bioinspired systems for the investigation of molecular interactions in membrane models and for the production of devices for biosensors and environmental analysis
• Grantee: Luciano Caseli
• Support Opportunities: Regular Research Grants