Construction of an amperometric TG biosensor based on AuPPy nanocomposite and poly (indole-5-carboxylic acid) modified Au electrode

Abstract

A method is described for construction of an amperometric triglyceride (TG) biosensor based on covalent co-immobilization of lipase, glycerol kinase and glycerol-3-phosphate oxidase onto gold polypyrrole nanocomposite decorated poly indole-5-carboxylic acid electrodeposited on the surface of a gold electrode. The enzyme electrode was characterized by transmission electron microscopy, scanning electron microscopy, electrochemical impedance studies, Fourier transform infrared spectroscopy and cyclic voltammetry. Biosensor showed optimum response within 4 s at pH 6.5 and 35 °C, when polarized at +0.1 V against Ag/AgCl. There was a linear relationship between sensor response and triolein concentration in the range 50-700 mg/dl. Biosensor was employed for determination of TG in serum. Detection limit of the biosensor was 20 mg/dl. Biosensor was evaluated with 91-95 % recovery of added triolein in sera and 4.14 and 5.85 % within and between batch coefficients of variation, respectively. There was a good correlation (r = 0.99) between sera TG values by standard method (Enzymic colorimetric) and the present method. The biosensor was unaffected by a number of serum substances at their physiological concentration. Biosensor lost 50 % of its initial activity after its 100 uses over 7 months, when stored at 4 °C.

Construction of a Hydrogel Pectin-Based Triglyceride Optical Biosensor with Immobilized Lipase Enzymes

“…This optimum pH is similar to studies reported before, which used amperometry and electrochemical methods [35,36]. However, a different optimum pH is reported by Narang et al [37]. This difference can be caused by a different membrane matrix, type of substrate, enzyme, and immobilization method [38].…”

Polyindole and polypyrrole as a sustainable platform for environmental remediation and sensor applications

“…Fabricated electrodes exhibited ultrasensitivity and fast response to dopamine and enables the RP as a suitable enzyme system for dopamine detection in an aqueous solution. 283 . For TG concentrations in the range of 50-700 mg/dl, a linear response was observed.…”

Boosting the Electrochemical Performance of PI-5-CA/C-SWCNT Nanohybrid for Sensitive Detection of E. coli O157:H7 From the Real Sample

“…The = CH-N stretching vibration of the monomer near 890 cm −1 disappeared in the polymer spectrum. The peaks near 1,478–1,838 cm −1 showed the presence of carboxyl groups in the monomer I-5-CA and the polymer PI-5-CA ( Narang et al, 2013 ). Compared with the FT-IR spectra of PI-5-CA, the FT-IR spectra of PI-5-CA/C-SWCNT nanocomposites showed a one-point positive shift in the C=C bond, which should be attributed to the π–π interaction between PI-5-CA and C-SWCNTs ( Yang et al, 2019 ).…”