LAUSR

Compared with traditional filter paper, high-purity cellulose membrane prepared via green pathway was used to attempt to enhance their performance of glucose detection. In this work, cellulose-based strips (CBS) for the low concentration of glucose detection had been designed based on a fast, sensitive and easy enzyme colorimetric assay from the porous and high-purity cellulose membranes (CM). Different from the traditional paper-based sensors that were made of commercially available filter paper, the cellulose-based membranes matrix was fabricated by a "green" route that cellulose was dissolved in an aqueous NaOH/urea solution, and then modified by sodium periodate oxidation method to immobilize the glucose oxidase (GOX) and horseradish peroxidase (HRP) with Schiff-base reaction. The structure and properties of CM and CBS were characterized by SEM, EDS, FT-IR and XPS, etc. SEM images showed a porous, interpenetrating structure of CM, which benefited to the enzyme immobilization and enzymatic reaction. When glucose solution was dropped onto the CBS, the color changing from colorless to blue was only 5 min. The limit of detection (LOD) is 0.45 mM in the linear range of glucose from 1 to 11 mM. Moreover, the CBS had also been successfully used for glucose determination in real urine samples, and the color changes can be easily recorded by a simple camera to achieve the semi quantitative detection of glucose. This work provided a new design strategy for the cellulose-based functional materials which could be applied in biosensors, drug carriers and biomedicine. Keywords: Cellulose-based strips; Enzyme colorimetric assay; Glucose detection; Sodium periodate oxidation method; Schiff-base reaction.