A rapid and sensitive method for determination of trace amounts of glucose by anthrone-sulfuric acid method

Anthrone-sulfuric acid assay, a rapid, sensitive microanalytic method, was modified to quantify carbohydrate in a colorimetric tube. A single test methodology was applied to design and optimize the factors including solvents, heating, anthrone concentration, sulfuric acid concentration, amount of anthrone reagent and reaction duration. The tube with the reaction system of total volume 5.0 mL, which contained 3.0 mL of anthrone-sulfuric acid solution, 1.0 mL of distilled water and 1.0 mL of glucose solution, was kept in a water bath at 93°C for 15 min. Under these conditions, the absorption values at 520 nm for different glucose concentrations were in linear relationship with the fitting equation of linear regression with a correlation coefficient R of 0.997. The linear range was 0 ~ 0.01 mg/mL of glucose. Standard addition test results revealed that the method has a relative deviation of 2.42%, the tagged recoveries were 101.4%. The method developed in this work proved to be simple, valid, stable, and repeatable with little interference based on the precision test and the interference test, and could be applied for total sugar content determination.