Development of a label-free electrochemiluminescence biosensor for the sensitive detection of porcine gelatin using carbon nanostructured materials

Abstract

In this study, a carbon nanofiber fabricated screen-printed electrode (CNF-SPE) was modified using carbon nano-horns (CNHs) and nafion (NAF) for the development of a label-free electrochemiluminescence (ECL) biosensor. The goal was to design a robust and sensitive biosensor for the detection of porcine gelatin in food products, which will globally have a significant impact on the halal food industry. Gelatin derived from porcine has major religious and ethical concerns worldwide and its use is gradually increasing in food-based products without proper monitoring and observation. Henceforth, a biosensor was developed over a CNFs-SPE/CNHs/NAF platform by immobilizing biorecognition molecules (anti-gelatin), followed by non-specific blocking by 0.1% bovine serum albumin (BSA). Further, energy dispersive X-ray (EDX) and Fourier-transform infrared (FTIR) spectroscopy were employed to characterize the CNHs/NAF nanocomposite. Moreover, biosensor development was studied both by ECL and electrochemical impedance spectroscopy. Interestingly, the developed biosensor CNFs-SPE/CNHs/NAF/anti-gelatin/BSA demonstrated extensive linearity of 1 pg mL⁻¹ to 8 ng mL⁻¹ with a detection limit of 1 pg mL⁻¹. Therefore, with a demonstrated wide linear range and low detection limit, this proposed biosensor could be used to analyze real food samples. Furthermore, the biosensor showed remarkable reproducibility for porcine gelatin detection.