Colorimetric biosensing of triglyceride in waste water using lipase immobilized ZnO nanoparticle enriched chitosan nanoconjugate

Abstract

We constructed a liquid-phase colorimetric biosensor to detect Triglycerides (TG) contamination in water using a Porcine Pancreatic Lipase Immobilized Zinc – chitosan nanocomposite matrix with Phenolsulfonphthalein as the chromophore. The nanoparticle-augmented matrix was characterized using an SEM—the change in the chromophore colour from red to yellow indicated vegetable oil hydrolysis and fatty acid release. The biosensor showed a LOQ between 25–500 µg/mL at an operating temperature between 25–45 °C, over a pH range of 4–9 within 5 minutes. The biosensor showed resilience to samples contaminated up to 50 times the BIS permissible limits for iron, copper and manganese. The sensor showed repeatability of nearly 100% with the LOD 3 µg/mL, sensitivity 47.1 U/µg/cm2 and retained up to 80% of its activity till the 10th day when stored at 10 °C. A fully adept version of the biosensor can be applied to detect TG in water and wastewater.

KEYWORDS:

• Biosensor
• colorimetry
• triglycerides
• immobilized lipase
• nanoconjugate
• nanoparticle

Acknowledgement

The authors are grateful to the Department of Bioengineering and Biotechnology at the Birla Institute of Technology (BIT), Ranchi, for an engaging environment. The authors acknowledge the support from the Central Instrumentation Facility, BIT and BIT, Ranchi, for their support. MBI acknowledges BIT, Ranchi, for their Institutional Research Fellowship.

Data availability

Not Applicable

Disclosure statement

No potential conflict of interest was reported by the author(s).