Article details

Journal
Biotechnology and Food Science
Volume 78 Number 2
Year
2014
Title
The study of phenylboronic acid optical properties towards creation of a glucose sensor
Authors

Katarzyna Kur-Kowalska, MaƂgorzata Przybyt, Ewa Miller*
Lodz University of Technology, Institute of General Food Chemistry,
Stefanowskiego 4/10, 90-924 Lodz, Poland orologi replica italia
*ewa.miller@p.lodz.pl


Pages: 101-110
Abstract
The article presents influence of pH and glucose concentration on phenylboronic acid (PBA) fluorescence studied by steady-state and time-resolved measurements. Fluorescence of PBA decreases with growing pH. These changes reflected acid-base equilibrium of PBA and allowed to estimate value of pKd as 9.2, which is comparable with literature data. Fluorescence intensity of phenylboronic acid is quenched in presence of glucose. The effect of quenching is more pronounced with increasing pH. At pH 7 quenching can be described by Stern-Volmer equation, at pH 8 and 9 by modified one. The obtained quenching constants are growing with pH increase. The quenching of phenylboronic acid fluorescence by glucose is a static one zegarki repliki, which is confirmed by time-resolved measurements. Two lifetimes were found for fluorescence decay of phenylboronic acid. The lifetimes are practically independent on pH and glucose concentration and also fraction of both lifetimes are nearly the same. The obtained Stern-Volmer constants can be interpreted as apparent equilibrium constants of ester formation between acid and glucose.
Keywords
boronic acid derivatives, glucose sensor, optical sensor, fluorescence quenching
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