Biosensors based on immobilization of biomolecules in sol-gel matrices - Electrochemical Sensors, Biosensors and Their Biomedical Applications - page 523

Although various sol-gel precursors and sol-gel preparation methods have been intro-
duced, there is still a great need to explore more mild biocompatible matrices. The
long-term use and reduction of fi lm fouling though microbial growth or adhesion of
new matrices, which can inhibit the growth, have to be explored. This is possible by
developing new sol-gel precursor molecules, which are modifi ed with microbial inhi-
bition compounds or metal ions. The immobilized antibodies are showing promising
results in immunosensor design, but their stability and regeneration are limited, hence
more focus is needed in these areas to design robust immunosensors.
Relatively less work has been done on immobilization of plant and animal cells
and spores of microbes in silica matrixes. The main drawback is less viability of the
cells in sol-gel matrices. Thus more refi ned methods are required to utilize harness of
the whole cells entrapped in sol-gel matrices and biosensing applications. At the same
time studies such as interactions between sol-gel matrices and whole cells and meta-
bolic changes during immobilization have to be closely monitored for the exploration
of new matrices and methods.
16.6 ACKNOWLEDGMENTS
We gratefully acknowledge the fi nancial support of the National Science Funds for
Distinguished Young Scholars (20325518) and Creative Research Groups (20521503),
the Key (20535010) and General (20275017) Programs from the National Natural
Science Foundation of China, the Specialized Research Fund for Excellent Young
Teachers from Ministry of Education of China and the Science Foundation of Jiangsu
(BS2006006, BS2006074). V.S. Tripathi and V.B. Kandimalla are extremely thankful
to Nanjing University for providing postdoctoral fellowships.
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