Analytical Sciences


Abstract − Analytical Sciences, 19(11), 1477 (2003).

Application of Polyaniline/Sol-Gel Derived Tetraethylorthosilicate Films to an Amperometric Lactate Biosensor
Asha CHAUBEY, K. K. PANDE, and B. D. MALHOTRA 
Biomolecular Electronics & Conducting Polymer Research Group, National Physical Laboratory, Dr K. S. Krishnan Marg, New Delhi-110012, India
The electrochemical entrapment of polyaniline (PANI) onto sol-gel derived tetraethylorthosilicate (TEOS) films deposited onto indium-tin-oxide (ITO) coated glass has been utilized for immobilization of lactate dehydrogenase (LDH). The performance of these sol-gel/PANI/LDH electrodes has been investigated as a function of the lactate concentration, applied potential, pH of the medium and interferents. The amperometric response of the electrodes under optimum conditions exhibited a linear relationship from 1 mM to 4 mM. An attempt has been made to extend the linearity up to 10 mM for lactate by coating an external layer of polyvinyl chloride (PVC) over the sol-gel/PANI/LDH electrodes with a correlation coefficient of 0.89. These sol-gel/PANI/LDH electrodes have a response time of about 60 s, a shelf life of about 8 weeks at 0 - 4°C and have implications in a lactate biosensor.