Graphene Oxide Enabled Colorimetric Detection of Triglyceride

Graphene oxide (GO) is the most sought-after constituent in developing solutions for problems across biosensing and diagnostics to implants, automotive to space missions, and manufacturing to waste rehabilitation. GO is costly if procured externally and time-intensive if produced by conventional processes. In this paper, GO is synthesized using an efficient, cost-effective method at a much faster rate. The quality of GO is at par with the standards, and techno-economic analysis reveals that the proposed method took 20–25% less time for synthesis than practised methods. The proposed method is profitable, and the payback period is around 6 to 7 months. Lipase, successfully immobilized on synthesized GO, showed four times free enzyme activity with 75% enzyme loading. This work indicates that the GO from the proposed method, on ultrasonication generates nanometric GO (nano-GO) that are highly biocompatible for lipase-immobilized biosensor applications. The biorecognition module fabricated using GO showed a response time of under 10 min and compatibility with samples with pH between 6 and 9 with a temperature range of 20–45 °C. The biosensor showed a 5.28 µg/mL limit of detection (LOD) and a 1 U/µg/mL sensitivity with a limit of quantitation (LOQ) of 5–250 µg/mL. Retention of 60% activity when stored at 10 °C after ten days was observed. The biorecognition module showed resilience to up to 30 mg/L of metal interferents and contaminants. The biorecognition was found to be significant for colorimetry-based paper biosensing.

A colorimetric biorecognition module to detect triglyceride (TG) was designed using graphene oxide (GO) nanomaterial, synthesized by modifying previously reported methods. The method reported in the study is 20 to 25% fast and simultaneously provides an excellent quality product. The proposed method was 200% more economical. It was observed that as part of the solid matrix, the GO NPs are an excellent candidate for lipase-immobilized colorimetric biosensors for triglyceride detection. The matrix met the necessary benchmarks of a colorimetric biosensor.