þÿ<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>JBPC Vol. 7, 2, 2007 ABSTRACT </title> </head> <body link="#0000FF"><center><h1><font color="#006600">The Journal of Biological Physics and Chemistry</font></h1></center> <p></p><p></p> <b><center>2007<p>Volume 7, Number 2, p.p. 65 68</center></b> <br> <div> <p><b><font size=+2> <I>In situ</I> monitoring of adsorbed enzyme activity </font></b></p> <p> <b> M.G. Cacace<SUP>1,2,*</SUP> and J.J. Ramsden<SUP>3,4</SUP> </b> <br> <br> <i> <SUP>1</SUP> National Research Centre for Germinal Cells, Via Tommaso Pendola 62, 53100 Sienna, Italy<BR> <SUP>2</SUP> Institute for the Study of Nanostructured Materials, CNR, Via P. Gobetti 101, 40129 Bologna, Italy<SUP> </SUP><BR> <SUP>3</SUP> Department of Biophysical Chemistry, Biozentrum, 4056 Basle, Switzerland<BR> <SUP>4</SUP> Department of Materials, Cranfield University, Bedfordshire, MK43 0AL, UK <SUP> </SUP> </i></p> <P align=justify> The activity of an adsorbed urease monolayer is rapidly and conveniently determined<I> in situ</I> by monitoring refractive index shifts in the vicinity of the protein layer due to the change in selective dispersion of a<I> p</I>H indicator responding to the enzymatic decomposition of urea to ammonia. An elementary treatment of the optical and hydrodynamic phenomena is given for deriving the enzyme turnover number. </p> <b>Keywords: </b> enzyme immobilization, optical waveguides, dispersion, urease, carminic acid </p> <br> </div> <p></p> <center><p><i><font size=-1><a href="jbpc20707.html">back to contents</a></font></i></p></center> </body> </html>