ABSTRACT
The level of fructosamine was determined in the serum of 278 individuals ranging in age from 20 to 80 years who passed a physical check-up. The 130 males and 148 females had mean ages + standard deviation of 44.0+15.0 and 40.3+12.0 years, respectively. Serum fructosamine concentration was assayed using nitroblue tetrazoleum (NBT) reduction in alkaline medium. The reference values of serum fructosamine were 226 µmol/L to 296 µmol/L (Mean = 260.7, SD = 17.6 µmol/L). The serum fructosamine is unaffected by sex. Effect of food intake on fruc tosamine level has been carried out on a group of healthy subjects (n = 36). The means and SDs of serum fructosamine at eight-hour fasting, two-hour post-prandial and non-fasting specimens were studied and values of 269.4+17.9, 269.3+14.8 and 268.6+15.3 µmol/L respectively, were obtained. Results reveal that food intake has virtually no effect on fructosamine values (Analysis of variance p>0.05). Parallel assays of 46-paired sera was Y = 17.5 + 0.95 X, whereas X and Y were serum and plasma fructosamine levels, respectively. Values of plasma fructosamine were statistical significantly difference from those of serum (p<0.001). A small discrepancy of 1.9 percent was observed. Thus, whenever plasma is used as sample for fructosamine test, a slightly higher value of fructosamine would be obtained.
ABSTRACT
Tested serum of donors from the Blood Bank unit of Siriraj Hospital was collected. Only negative hepatitis B-antigen determined by RPHA (reverse passive haemagglutination) method was selected. The sera were pooled as one pooled serum. Filtrations were performed after adjusting some biochemical constituents. To obtain lyophilized serum, the pooled serum was subjected to freeze-dry process. It was divided into aliquot of 5.0 ml in each vial, then quick freezed and dried in the lyophilizer. Precision of between-vial filling volume was studied. We found that the coefficient if variation was 0.01%. Reconstitution of the lyophilized serum before use was performed by adding 5.0 ml of distilled water to each vial. The coefficient variation of between-vial biochemical constituents was found to be less than 0.5%. The precision of 19 routine biochemical tests in these Home-Made lyophilized human serum were compared to those of 3 batches of well-known commercial control materials (ORTHO, MONITROL, VALIDATE). By F-test analysis, the coefficient variation of most biochemical tests in the Home-Made lyophilized human serum was not significant different from those of the commercial ones (P>0.05). The long-term consistency of the biochemical constituents was studied. In a duration of one year, from March 1985 to February 1986, three-month periods means and standard deviations were analyzed. The results showed no significant difference for these period of study (P>0.05). Since 1985, the Home-Made lyophilized serum has been used as internal control material in our Central Clinical Chemistry Laboratory, Faculty of Medicine Technology, Mahidol University in place of imported control serum. The external control evaluation was successfully reported by the International External Quality Control Assessment Scheme. (Birmingham UK) and the improvement of Overall Mean Running Variance Index Score (OMRVIS) is obviously seen in the graphic curve.