| 초록 |
Purpose: If early diagnosis is not made, patients with metabolic disorders as homocystinemia rapidly progress to physical defect or mental retardation resulted in storage of the toxic material into the brain. Therefore, it is necessary to develop an analytical method for a rapid screening and/or correct confirmation diagnosis. Methods: The standard solution of sulfur amino acids spiked plasma was subjected to protein precipitation with methanol, and then consecutively derivatized with trimethylsilyl (TMS) and trifluoroacyl (TFA) and determined by GC-MS. The formation of TMS derivative of the hydroxyl and TFA derivative of amino functional group was performed by BSTFA and MBTFA, respectively. Selective ion monitoring (SIM) mode was used for quantification with selected specific ions. Results: A calibration curve on standard spiked pooled plasma showed a linear relationship with correlation coefficient of 0.9936-0.9992 for all compounds over the range of 0.1-300 ng. The precision and accuracy were within S.D. of 1-15% and RSD of 1-15% for intra-day assay at 2 ng/mL, 15 ng/mL and 30 ng/mL. LOD and LOQ was 0.4 ng/mL and 4 ng/mL respectively. Conclusion: A rapid analytical method was developed to quantify sulfur amino acids and methyl malonic acid, after two-step derivatization procedure with good sensitivity and specificity on human plasma. Advantages of a new method are simplicity and rapidity. The method could be useful for routine analysis, diagnosis of homocysteinemia. |
