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51.
采用高效液相色谱法测定盐酸二氧异丙嗪的含量。色谱柱为 DIKMATMRPC18(4 .6 mm× 2 0 cm,5 μm) ,流动相为乙腈 - 0 .5 %磷酸二氢钾 -三乙胺 (5 0∶ 5 0∶ 0 .2 ) ,用磷酸调 p H值至 6 .8± 0 .1;流速为1.0 m L/ min,检测波长为 2 6 4nm。该法回收率为 99.6 % ,RSD=0 .6 1%。盐酸二氧异丙嗪在浓度为0 .0 184 8— 0 .0 4 312 mg/ m L范围内线性关系良好。相关系数为 r=0 .9999。该方法操作简便 ,结果准确可靠。  相似文献   
52.
F. Al-Rimawi 《Talanta》2009,79(5):1368-336
A simple, and stability-indicating liquid chromatographic method was developed and validated for the analysis of metformin hydrochloride and its related compound (1-cyanoguanidine) in tablet formulations. Liquid chromatography with a UV detector at a wavelength of 232 nm using a Nova-Pak silica column was employed in this study. Isocratic elution was employed using a mixture of ammonium dihydrogen phosphate buffer and methanol (21:79, v/v). This new method was validated in accordance with USP requirements for new methods for assay determination, which include accuracy, precision, specificity, linearity and range. The current method demonstrates good linearity over the range of 0.01-0.03 mg mL−1 of metformin hydrochloride. The accuracy of the method is 100.4%. The precision of this method reflected by relative standard deviation of replicates is 0.30%. Validation of the same method for 1-cyanoguanidine determination was also performed according to USP requirements for quantitative determination of impurities which include accuracy, precision, linearity and range, selectivity, and limit of quantification (LOQ). Low LOQ of 1-cyanoguanidine using this method enables the detection and quantification of this impurity at low concentration.  相似文献   
53.
秦宗会  谢兵 《光谱实验室》2005,22(5):1025-1027
通过紫外扫描,发现盐酸西布曲明在波长196nm、222nm处产生吸收,其中在196nm处吸收最大,从而建立测定西布曲明紫外光谱法。在196nm波长处,吸光度A与盐酸西布曲明的浓度在0—4.65×10-5mol·L-1范围内,遵守比耳定律,检出限1.513×10-7mol·L-1。本法操作简便快捷,灵敏度较高,体系稳定,用于曲美胶囊中的盐酸西布曲明的测定,结果令人满意。  相似文献   
54.
张轶华  姜建国  韩学静  张世亮 《色谱》2010,28(10):1005-1008
建立了高效液相色谱(HPLC)-双波长检测-梯度洗脱同时测定小儿氨酚烷胺颗粒中对乙酰氨基酚、咖啡因和马来酸氯苯那敏含量的分析方法。采用的色谱条件: 以Diamonsil C18色谱柱(4.6×200 mm, 5 μm)为分离柱,以乙腈和0.1%三乙胺水溶液(用磷酸调pH至3.7±0.5)为流动相进行梯度洗脱,流速1.0 mL/min,检测波长为280 nm和210 nm,柱温为30 ℃,进样量为5 μL。结果表明,对乙酰氨基酚、咖啡因和马来酸氯苯那敏的线性范围均比较宽(依次为2.4~60、0.14~3.6、0.019~0.48 μg),平均加标回收率均不低于99.0%,而且方法操作简单,重现性好,测定结果准确,可用于更好地控制该制剂的质量。  相似文献   
55.
《印度化学会志》2021,98(10):100170
Morus rubra (red mulberry) is a folk medicine used in management of diabetes. The aim of this article to investigate the antidiabetic activity of hydro alcoholic leaf extracts of Morus rubra in the sprague dawley male rats (SD) model. Authentication of plant material, total Phenolic contents, total flavonoid contents, HPLC analysis, in-vitro antioxidant activity, acute toxicity, in-vivo oral glucose tolerance test, in-vivo STZ induced antidiabetic activity along with biochemical parameters (triglycerides, low-density lipoprotein, high-density lipoprotein, total cholesterol, serum glutamate phosphotransferase, serum glutamate oxaloacetic acid transferase, urea and creatinine). The total phenolic contents 60.32 ​± ​0.80 ​mg/g GAE (gallic acid equivalent) were found higher in ethanolic extract. The total flavonoids 16 ​± ​0.42 ​mg/g QE (quercetin equivalent) were found in petroleum ether extract. M. rubra leaf extracts were tested by HPLC for qualitative and quantitative analysis. 100 ​mg of the dried powder of Morus leaves was dissolve in methanol: water (80:20, v/v) for analysis. Chromatograms of HPLC show the presence of chlorogenic acid 0.55 mg/gm, quercetin 1.90 ​mg/g, isoquercetin 0.68 mg/gm and rutin 0.10 mg/gm. IC50 (Inhibitory concentration) value has been found higher in chloroform extract (92.89 ​μg/ml). Metformin drug is used for positive control, which causes 14.6% improvement in glucose tolerance while M. rubra has been found 11.4. % at the dose of 300 ​mg/kg body wt in normal rats. In STZ treated diabetic rats, it reduces 13.0% blood glucose level while metformin reduces 21.9% up to dosing level of 300 ​mg/kg body wt. It produces reduction in biochemical parameters like, total cholesterol (TC), triglycerides (TG), SGPT, LDL, urea, creatinine and SGOT while HDL has been increased. Results show the hydro-alcoholic leaves extract of Morus rubra exhibited antidiabetic, antioxidant and hypolipidemic properties. This suggests that M. rubra has great potential to develop novel antidiabetic drug to manage this disastrous disease.  相似文献   
56.
林园 《光谱实验室》2007,24(5):976-977
研究了火焰原子吸收光谱法测定盐酸金霉素中Zn、Fe、Mg的方法.方法的检出限Zn:0.006、Fe:0.03、Mg:0.003 mg/L,回收率98%-104%,RSD小于1.45%.结果表明,该方法准确、快速、结果令人满意.  相似文献   
57.
陈玉花 《光谱实验室》2006,23(6):1147-1149
荧光薄层扫描法测定沙日嘎-4汤中盐酸小檗碱和盐酸巴马汀的的含量.沙日嘎-4汤中盐酸小檗碱的含量为0.16mg/0.2g;盐酸巴马汀的含量0.12mg/0.2g;RSD为0.36%、0.45%;平均回收率为98%、103%.该方法操作简单,分离效果好,灵敏度高,可作为沙日嘎-4汤的质量控制标准.  相似文献   
58.
采用十八烷基硅烷键合硅胶(200mm×4.6mm,5μm)为固定相,以0.01mol/L磷酸二氢钾-甲醇-三乙胺(95∶5∶0.5)为流动相(用磷酸调节pH值至3.0),在210nm波长测定金贝痰咳清颗粒中盐酸麻黄碱含量;以乙腈-0.4%磷酸溶液(13∶87)为流动相,在327nm波长测定金贝痰咳清颗粒中绿原酸含量。盐酸麻黄碱在0.204—1.02μg范围内线性关系良好(r=0.9998),回收率为99.31%(RSD为0.70%)。绿原酸在0.09—0.45μg范围内线性关系良好(r=0.9996),回收率为99.05%(RSD为0.65%)。该方法简便准确,重复性好,处方中其他成分对测定无干扰,可作为本产品的质量控制方法。  相似文献   
59.
介绍一种高效液相色谱法测定含量的不确定度计算方法.通过黄柏中盐酸小檗碱含量测定结果,对产生不确定度的各分量进行计算,研究测量不确定度的主要分量,以控制检验环节的质量,保证结果准确度.  相似文献   
60.
A novel and simple chemiluminescence (CL) method has been developed and validated for determination of metformin. This method is based on hydroxyl radical chemiluminescence—the hydroxyl radical generated by reaction of Cu(II) and hydrogen peroxide oxidizes rhodamine B (RhB) to produce weak CL which can be enhanced by metformin. At the same time, metformin molecularly imprinted polymer (MIP) was synthesized. After enrichment based on the selectivity of metformin-MIP, the CL method was successfully applied to the determination of metformin in human serum. The linear range was from 1.0×10−8 to 1.0×10−6 g mL−1 and the detection limit was 4×10−9 g mL−1. The relative standard deviation at 2.0×10−7 g mL−1 by use of MIP was 3.67% (n=7).  相似文献   
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