Simultaneous Determination of 6 Organic Solvents in Tosufloxacin Tosylate by Headspace GC / 中国药房

OBJECTIVE:To establish a method for the residual simultaneous determination of methanol,alcohol,dichlorometh-ane,n-hexane,tetrahydrofuran and benzene in tosufloxacin tosylat. METHODS:Headspace GC was performed on the capillary col-umn with 6%cyanopropylphenyl-94%dimethylpolysiloxane(DB-624)as fixative lipid,temperature programmed,the inlet temper-ature was 180 ℃,detector was flame ionization detector with temperature of 300 ℃,carrier gas was high purity N2 at a flow rate of 1.5 mL/min,split ratio was 10:1,headspace equilibrium temperature was 100℃,equilibrium time was 40 min,headspace sam-ple volume was 10 mL,and the headspace sample volume was 1 mL. RESULTS:The linear range was 178.3-1782.7 μg/mL for methanol (r=0.9991),301.2-3012.1 μg/mL for alcohol(r=0.9997),33.81-338.10 μg/mL for dichloromethane(r=0.9993), 18.02-180.22 μg/mL for n-hexane(r=0.9991),43.26-432.58 μg/mL for tetrahydrofuran(r=0.9991)and 0.1268-1.2681 μg/mL for benzene(r=0.9991);limits of quantification were 0.31,3.00,0.67,0.02,0.005,0.10 μg/mL,limits of detection were 0.15, 1.51,0.22,0.01,0.001,0.05 μg/mL;RSD of precision test was no higher than 3.1%;RSDs of methanol and n-hexane in stabili-ty and reproducibility tests were no higher than 5%;recoveries were 93.72%-102.20%(RSD=3.1%,n=9),90.10%-101.79%(RSD=4.0%,n=9),97.07%-103.11%(RSD=2.0%,n=9),92.38%-103.83%(RSD=3.9%,n=9),95.44%-103.62%(RSD=2.8%,n=9),and 94.00%-104.73%(RSD=4.1%,n=9). CONCLUSIONS:The method is rapid,sensitive,accurate,and suitable for the residual determination of methanol,alcohol,dichloromethane,n-hexane,tetrahydrofuran and benzene in tosufloxacin tosylat.

Study on inhibitory effect of reinioside C on asymmetric dimethylanginine-induced soluble interacellular adhesion molecule-1 expression and its mechanisms / 中华老年医学杂志

Objective To investigate the inhibitory effect of reiniosidc C (RC) on asymmetric dimethylarginine (ADMA)-induced soluble interacellular adhesion molecule-1 (slCAM-1) expression and its mechanisms. Methods Human umbical vein endothelial cells (HUVEC 12) were cultured.The level of slCAM-1 in the conditioned medium was determined by ELISA. Changes in intracellular reactive oxygen species (ROS) levels were determined by measuring the oxidative conversion of cell permeable 2', 7'-dichlorofluorescein diacetate (DCFH-DA) to fluorescent dichlorofluorescein (DCF) in fluorospectro- photometer, and the nuclear factor-κB (NF-κB) DNA-binding activity was determined by electrophoretic mobility shift assays (EMSA). Results sICAM 1 expressions [(138.02±16.40), (194.52±11.14), (274.28±13.11)ng/L]and the generation of ROS[(75.64±5.22),(100.18±11.15),(107.23±13.45)units] in HUVEC-12 were time dependently increased by ADMA (30 μmol/L). Furthermore, thc generation of ROS [(85.33±8.68), (70.69±7.65),(59.12±4.15)units], activation of NF-κB activity and expression of sICAM-1 [(336.58±23.32),(203.27±25.18) ,(174.13±14.53)ng/L] induced by ADMA were inhibited by reinioside C (1,3,10μmol/L) in a dose-dependent manner. This effect was found to be the same by L-arginine (0.5 mmol/L) as NOS substrate and by pyrrolidine dithiocarbamate (PDTC) (10 μmol/L)as inhibitor of NF-κB.Conclusions Reinioside C attenuates the increase of sICAM-1 induced by exogenous ADMA

Determination of six active components in three species of genus Swertia by HPLC multiwavelength with detection / 中国中药杂志

<p><b>OBJECTIVE</b>To develop an HPLC method for the quantification of six active components in three species (Swertia davidi, S. nervosa and S. mussotii) .</p><p><b>METHOD</b>The determination was performed on a Hypersil BDS colunm (4. 6 mm x 200 mm, 5 microm). Acetonitrile and 0.5% phosphoric acid solution were used as the mobile phases with a gradient elution. The flow rate was 1.0 mL x min(-1). The UV detection wavelength was at 240, 274, 325 and 334 nm. The column oven temperature was at 25 degrees C.</p><p><b>RESULT</b>Six components were separated commendably in 60 minutes. The calibration curves of swertiamarin, gentiopicroside, norswertianolin, swertianolin, demethylbellidifolin and bellidifolin were in good linearity over the range of 0.520-20.8, 0.202-8.06, 0.107-4.28, 0.097-3.86, 0.094-3.77, 0.101-4.02 microg, respectively (r = 0.999 9). The average recoveries were 98.7%, 98.1%, 98.3%, 98.8%, 98.1% and 98.6%, respectively, and the RSD were less than 3.0% (n = 6).</p><p><b>CONCLUSION</b>The method is accurate,simple and reproducible, and can be used to control the quality of Swertia.</p>

Determination of caffeic acid in leaves of Ipomoea batatas (Simon Ⅰ) by HPLC / 中草药

Object To develop a method for the determination of caffeic acid in Simon Ⅰ. Methods An HPLC method was developed. Kromasil C 18 column and methanol acetic acid as mobile phase. Results Linearity was found in the range of 10 33 165 28 ?g/mL, the average recovery was 99 38%, RSD=1 36%(n=6). Conclusion This method is reliable, accurate and suitable for the determination of caffeic acid.