Capillary gas chromatographic determination of methylglyoxal from serum of diabetic patients by precolumn derivatization with 1,2-diamonopropane.

Capillary gas chromatographic (GC) determination of methylglyoxal (MGo) was developed on the basis of precolumn derivatization with 1,2-diaminopropane (DAP) at pH 3. The elution was carried out on an HP-5 (30 m x 0.32 mm i.d.) connected with FID. The linear calibration curve was obtained for MGo within 0.09-1.04 microg/ml with detection limit of 40 ng/ml. Dimethylglyoxal (DMGo) also formed derivative with DAP and eluted and separated from MGo at column temperature 100 degrees C for 1 min with heating rate 30 degrees C/min up to 200 degrees C with run time 4.6 min. The nitrogen flow rate was 1.5 ml/min with split ratio of 10:1, v/v. MGo was determined from serum and urine of diabetics and healthy volunteers. The amounts of MGo from serum and urine of diabetic patients were 0.180-0.260 microg/ml and 0.170-0.250 microg/ml with relative standard deviation (R.S.D.) within 1-4% and 1-3%, respectively. The amounts of MGo from serum of healthy volunteers were 0.032-0.054 microg/ml with an R.S.D. of 1.5-3%. DMGo was not detected from the biological fluids and was used as an internal standard.