Immobilization of platinum nanoparticles and glucose oxidase on eggshell membrane for glucose detection

A novel glucose biosensor based on the catalytic effect of platinum nanoparticles (PtNPs) on the enzymatic reaction for the glucose determination has been developed. PtNPs were in-situ synthesized on the surface of the eggshell membrane (ESM) upon which glucose oxidase (GOx) had been simultaneously immobilized accompanied by the synthesis of the PtNPs to produce a GOx-PtNPs/ESM. The glucose biosensor was fabricated by positioning the GOx-PtNPs/ESM on the surface of a dissolved oxygen sensor. The glucose concentration was quantified by the decrease of dissolved oxygen. The effect of the amount of K₂PtCl₄ (0.1 M), the volume of the GOx (1%, w/v), reaction time, pH, phosphate buffer concentration and temperature on the response of the glucose biosensor were studied in detail. This biosensor exhibited a response time of less than 30 s, a wide linear concentration range of 10-225 μM and a detection limit of 5 μM, good repeatability (RSD = 1.03%, n = 10), and satisfactory reproducibility (RSD = 0.54%, n = 5). The biosensor retained 90.0% of its initial response after 8 months at 25 °C. Common interferents such as d-fructose, citric acid, sucrose, l-ascorbic acid and so on did not any give significant interference. The proposed biosensor was successfully applied for the determination of glucose concentration in human blood serum with recoveries between 93.6% and 102.8%.