ABSTRACT
Objective: To establish an ion chromatography (IC) method to determine the content of chloride ion and sulfate ion in ethylparaben, and evaluate the quality status of chloride ion and sulfate ion in ethylparaben at different levels.Methods: Ion chromatograph was used.The column was Dionex IonPac AS 18 (250 mm ×4 mm,5 μm) using potassium hydroxide as the mobile phase with gradient elution, the flow rate was 1.0 ml·min-1 , the injection volume was 25 μl, and the quantitative method was standard curve.Results: The method showed good linear relationship within the range of 0.02-4.00 μg·ml-1 for chloride ion (r=0.999 9) and 0.10-10.00μg·ml-1 for sulfate ion (r=0.999 5).The average recovery was 90.12% (RSD=3.4%) and 85.54% (RSD=6.2%) for chloride ion and sulfate ion, respectively (n =9).The content range of chloride ion and sulfate ion was 0.000 3%-0.015 7% and 0.000 9%-0.024 4% in 63 batches of samples, respectively.Conclusion: The established method is simple, fast and accurate, which can be used to determine the contents of chloride ion and sulfate ion in ethylparaben and is helpful to its quality control.
ABSTRACT
OBJECTIVE:To establish a method to determine and compare the contents of sodium benzoate in medicinal(phar-maceutical excipients and active pharmaceutical ingredients) and non-medicinal (chemical reagents and food additives) grade. METHODS:HPLC was conducted for content determination,SPSS 18.0 software was adopted to compare the results. The column was Purospher STAR LP RP-18 endcapped with mobile phase of acetotrile-0.02% formic acid(adjusted pH to 4.0 with aqua ammo-nia)(30∶70,V/V)at a flow rate was 1.0 ml/min,the detection wavelength was 230 nm,column temperature was 35 ℃,and vol-ume injection was 20 μl. RESULTS:The linear range of sodium benzoate was 10.5-525.3 μg/ml(r=0.999 9);RSDs of precision, stability,reproducibility and durability tests were lower than 0.5%;recovery was 99.38%-101.26%(RSD=0.56%,n=9). The av-erage contents of sodium benzoate in medicinal and non-medicinal grade were between 99.400%-99.875%,but the average content of non-medicinal grade is lower than the medical grade. CONCLUSIONS:The method is accurate and simple with high specificity and good reproducibility,and can be used to determine and compare the content of sodium benzoate in medicinal and non-medici-nal grade.
ABSTRACT
OBJECTIVE@#To establish a new high performance liquid chromatography (HPLC) method for determining the concentration of cefazolin, cefradine, cefoperazone and cefotaxime in blood and urine, as well as to investigate its applicability.@*METHODS@#Protein in blood and urine was precipitated directly by acetonitrile with acetanilide was used as the internal standard using Agilent Zorbax SB-Aq column (250 mm x 4.6 mm, 5 microm). The mixed solvents of water (triethylamine 0.12%, acetic acid 0.12%) and acetonitrile were used as the mobile phase to separate cephalosporins using gradient elution method at 1 mL/min (flow rate) and 254 nm (detection wavelength).@*RESULTS@#The working curve of four cephalosporins showed a good correlation (r = 0.9993), with the detection limit up to 0.01 microg/mL. The recovery rate was more than 81.2%.@*CONCLUSION@#This method is fast, easy and accurate. It is suitable for biological analysis of the 4 cephalosporins of the blood and urine in practical cases.
Subject(s)
Adult , Humans , Male , Anti-Bacterial Agents/urine , Cefazolin/urine , Cefoperazone/urine , Cefotaxime/urine , Cephalosporins/urine , Cephradine/urine , Chromatography, High Pressure Liquid/methods , Forensic Toxicology , Sensitivity and Specificity , Specimen HandlingABSTRACT
OBJECTIVE@#To establish a new method for the analysis of paraquat in blood and urine by sodium borohydride/nickel chloride chemical reduction-gas chromatography/thermionic specific detector.@*METHODS@#An initial procedure of precipitation was performed by adding hydrochloric solution with sodium chloride and a mixture of chloroform and ethanol. Then the analyte contained in supernatant was reduced by a reduction system of sodium borohydride and nickel chloride and extracted by acetic ether. Ethyl paraquat (EPQ) was used as internal standard. GC/TSD was used to identify and quantify the analyte.@*RESULTS@#The limits of detection (S/N=3) in blood and urine were 0.002 and 0.004 microg/mL, respectively. The linear ranges were 0.050-30.0 microg/mL. Correlation coefficients in blood and urine were 0.999 and 0.998, respectively. The recoveries exceeded 80% both in blood and urine.@*CONCLUSION@#This method is applicable for quantification of paraquat in biological fluids.