Detection of glucose by silver nanoplates paper-based sensor

Abstract

Silver nanoplates (AgNPls) were employed to detect a low level of hydrogen peroxide (H2O2) and glucose based on the decomposition of AgNPls. A new AgNPls-modified paper was fabricated by depositing AgNPls on a filter paper coated with (3-mercaptopropyl) trimethoxysilane (MPTMS). For H2O2 detection, the color of AgNPls-modified paper was bleached due to the oxidation of AgNPls by H2O2, when immersed in H2O2 solution. It could be used to detect H2O2 in the concentration range from 0.7 to 3.0 mM by naked eyes detection and the quantitative data was measured via ImageJ software. For glucose detection, glucose oxidase was added into urine samples to react with glucose and generate H2O2. AgNPls-paper strip was prepared and used in this method. The standard addition method and sample dilution were performed to overcome the matrix effect from human urine. Chloride, sulfate and phosphate ions in urine samples were eliminated by adding AgNO3 into the urine sample solutions to form precipitates. In the determination of glucose in urine samples, the dynamic linear range was in the range from 0 to 1.4 mM. The recovery of glucose added to urine samples in the range of 94 to 105% was obtained with the relative standard deviation of the results in the range of 5.9–21.4%. The paper-based method could be used for glucose detection in human urine with acceptable accuracy and precision.