A Novel Fully Enzymatic Method for Determining Glucose and 1,5-Anhydro- d -Glucitol in Serum of One Cuvette

The aim of the study was to set up a novel fully enzymatic method for screening glucose and 1,5-anhydro- d -glucitol (1,5-AG) in one cuvette. We have determined glucose and 1,5-AG, based on glucokinase (GK) converting glucose to G6P, a compound that can be catalyzed ultimately into 6-PGA by G-6PD and its coenzyme NADP + , and then calculated glucose concentration according to absorbance variety. Furthermore, pyranose oxidase was used to oxidize 1,5-AG with the formation of 1, 5-anhydro-fructose and H 2 O 2 . Measurement was done according to Trinder’s reaction principle. The mean within-run and day-to-day precision (CV) of this method for glucose was 0.88% and 1.4%, and also that for 1,5-AG was 1.05% and 1.94%, respectively. The mean recovery rate of two targets was 100.2% and 101.6%, respectively. The correlation ( R 2 ) between the results of 1,5-AG obtained with our proposed method ( y ) and those obtained with LanaAG method ( x ) was 0.999 ( y = 1.002 x − 0.675 μmol/l; n = 86), and the correlation ( R 2 ) of glucose between the results obtained with our GK method ( y ) and those obtained with recommendatory hexokinase method ( x ) was 0.9999 ( y = 1.0043 x + 0.1229 mmol/l; n = 86). The reference range (95%) of serological glucose and 1,5-AG was 3.7 to 5.7 mmol/l (4.70 ± 0.51 mmol/l) and 83.1 to 240.7 μmol/l (161.9 ± 40.2 μmol/l), respectively; and there was no difference with age and sex ( P > 0.05). This newly developed method was dependable and steady-going, with analysis automatization, and allows quicker and easier measurement of serum glucose and 1,5-AG in one identical reaction cuvette in-phase than previously described methods.