ABSTRACT
Two methods including gas chromatography tandem mass spectrometry (GC-MS/MS) and high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) were established to detect common alkyl sulfonates and aryl sulfonates genotoxic impurities. Four alkyl sulfonates and methyl benzenesulfonate were determined by GC-MS/MS using butyl methanesulfonate as the internal standard, the chromatographic column was HP-5MS UI (30 mm × 0.25 mm, 0.25 µm), the carrier gas was helium, the flow rate was 1.0 mL·min-1 in a constant flow mode, the sample inlet temperature was set to 250 ℃, the split ratio was 10∶1, and the initial temperature of the heating program was 80 ℃, maintained for 1 minute, and then increased to 240 ℃ at a heating rate of 30 ℃·min-1 for 2 minutes. The mass spectrometry detector was an electron bombardment ion source (EI source), the data collection condition was multi reaction monitoring mode (MRM), and method validation using the raw material of clinical drug citalopram hydrobromide as a sample. The results showed that the linear range of four alkyl sulfonates and methyl benzenesulfonate were good at 3-50 ng·mL-1 and 9-150 ng·mL-1, with a correlation coefficient of r > 0.999, The spiked recovery was 80%-120%. The detection limits were 1 and 3 ng·mL-1; Ten aryl sulfonates determined by LC-MS/MS, the chromatographic column was CSH Fluoro phenyl (100 mm × 2.1 mm, 1.7 µm), the mobile phase was methanol (B)-5 mmol·L-1 ammonium formate (D), with a flow rate of 0.2 mL·min-1, and gradient elution was performed. The gradient program (T/% B) was set as 0/20, 25/90, 35/90, 42/20. The mass spectrometer detector was electro spray ionization with positive ionization mode (ESI+), the data collection was in dynamic multi reaction monitoring mode (dMRM), and the method was validated using the raw material of the clinical drug citalopram hydrobromide as a sample. The results showed that the linear range of aryl sulfonates were good at 9-2 000 ng·mL-1, 3-100 ng·mL-1 and 0.9-30 ng·mL-1, respectively. The correlation coefficient r > 0.999, the spiked recovery was 80%-120%. The detection limits were 30, 1 and 0.3 ng·mL-1. Two detection methods did not detect potential sulfonate genotoxicity impurities in the above APIs. The established analytical methods are reliable and effective, which can provide reference for drug quality control and detection.
ABSTRACT
<p><b>OBJECTIVE</b>To analyze the phenotype and genotype of a family with congenital dysfibrinogenemia.</p><p><b>METHODS</b>Assays of coagulation, including activated partial thromboplastin time(APTT), pro-thrombin time(PT)and thrombin time(TT) were carried out with Sysmex CA-7000 in the proband and his family members. The quality and quantity of fibrinogen in plasma were determined by Clauss and electrophoresis, respectively. Fibrinogen and inconstituent were analyzed by Native-PAGE. All exon and exon intron boundaries of fibringen genes were analyzed by direct sequencing.</p><p><b>RESULTS</b>The proband had normal APTT, but prolonged PT and TT. The activity of fibrinogen in plasma was decreased while its quantity was normal. These abnormalities were also found in his sisters and daughter, while his wife was normal. Genetic analysis revealed heterozygous G1233A in the exon 2 of FGA which resulted in Arg16His missense mutation.</p><p><b>CONCLUSION</b>Inherited dysfibrinogenemia is caused by Arg16His mutation in exon 2 of FGA.</p>