Design and characterization of a biosensor with lipase immobilized nanoparticles in polymer film for the detection of triglycerides

High levels of triglycerides in blood can harden and block the arteries increasing the risk of heart disease and strokes. Triglycerides are important constituents of oils and fats used in various foods. The triglyceride content in commercial preparations of oils is estimated using conventional methods. In the present study, an electrochemical biosensor with lipase immobilized novel conductive polymer film has been developed for estimating triglyceride content in a variety of products. The portable biosensor can bring down the detection costs dramatically and can be used for varied purposes. It is based on cyclic voltammetry and has a three-electrode configuration system. Glassy carbon electrode is functionalized with nanoparticles embedded in polyethyleneimine and lipase is immobilized using glutaraldehyde. The strategy increases the electrochemical conductance manifold and overcomes the hindrance to lipase posed by membranes as it is oriented on the outside of the membrane. Thus, it increases the sensitivity and selectivity of detection. Results of scanning electron microscopy and FT-IR spectroscopy were used for characterizing the electrode surface. Linear range of the electrode for triglycerides is 100-500 mg/dL. The sensor was used successfully to determine triglyceride content in several real samples and the average recovery values lie from 95.47 % to 101.05 %.