Polyaniline nanotubes for impedimetric triglyceride detection

Polyaniline nanotubes (PANI-NT) based film electrophoretically deposited onto indium–tin–oxide (ITO) coated glass plate has been utilized for covalent immobilization of lipase (LIP), via glutaraldehyde (Glu), for triglyceride detection using impedimetric technique. It is shown that fatty acid molecules produced during triglyceride hydrolysis result in change in charge transfer resistance (RCT) of PANI-NT film with varying triglyceride concentration. LIP/Glu/PANI-NT/ITO bioelectrode has linearity as 25–300 mg dL−1, sensitivity as 2.59 × 10−3 KΩ−1 mg−1 dL, response time as 20 s and regression coefficient as 0.99. A low value of apparent Michaelis–Menten constant (∼0.62 mM) indicates high enzyme affinity to tributyrin. The LIP/Glu/PANI-NT/ITO bioelectrode has been utilized to estimate triglyceride in serum samples.