Rapid and highly sensitive colorimetric biosensor for the detection of glucose and hydrogen peroxide based on nanoporphyrin combined with bromine as a peroxidase-like catalyst

摘要

Peroxidase is a popular amplifier of biosensor signals, but its application is limited by chemical instability and expensive purification. We developed a sensitive, novel colorimetric biosensor to detect glucose and hydrogen peroxide (H_2O_2) using Zinc tetrakis (4-pyridinyl) porphyrin (ZnTPyP)-dodecyl trimethyl ammonium bromide (DTAB) nanoparticles (NPs) as peroxidase-like catalysts. ZnTPyP-DTAB NPs can oxidize colorless 3, 3′, 5, 5′-tetramethylbenzidine to a blue product (652 nm) in the presence of H_2O_2 via electron transport between porphyrin and bromine. This peroxidation mechanism was further verified using quantum chemical calculations. The detection limits of the colorimetric ZnTPyP-DTAB NP sensor were 0.15 and 0.5 μmol L~(-1) for glucose and H_2O_2, respectively, and the linear range was 3-70 and 8-50 μmol L~(-1), respectively. Recovery ratios of the biosensor in spiked human serum and saliva samples were 100 % ± 10 %. This simple method is robust, color stable, and reliable, thus providing an effective colorimetric biosensing platform for biomedical diagnosis.