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21.
Mohammed Shahid Ali Syed Rafiuddin Mohsin Ghori Aamer Roshanali Khatri 《Chromatographia》2008,67(7-8):517-525
A simple and specific hydrophilic interaction liquid chromatography (HILIC) procedure for the quantification of metformin
hydrochloride (MFH) and its impurities in bulk pharmaceuticals and finished dosage forms has been developed. The method is
based on hydrophilic interaction of the analytes with silica. The influence of the weaker solvent, acetonitrile, pH and the
nature and ionic strength of the buffer was studied. Linearity range and percent recoveries for MFH were 100–400 μg mL−1 and 100.62%, respectively. Good validation data were obtained for all compounds. The method separates impurities cyanoguanidine
(CGD), melamine (MLN) and other degradation products with a run time of less than 13 min. Degradation studies involved thermal
stress, hydrolysis at various pHs and chemical and photolytic oxidation. 相似文献
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Introduction Metformin (1,1-dimethylbiguanide) (Fig. 1) is an oral anti-hyperglycemic agent used in the treatment of non-insulin-dependent diabetes mellitus (type Ⅱ). Owing to its weight-decreasing and serum lipid-normalizing effects, it is especially recommended for obese patients[1,2] Various analytical methods have been described for the measurement of metformin in biological fluids, including gas chromatography(GC)[3-5], capillary electrophoresis (CE)[6] and HPLC[7~16]with UV detection[7-12,17] HPLC-Mass spectrometry (LC/APCIMS/MS ) offers an attractive alternative to HPLC[18]. 相似文献
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Simultaneous analysis of metformin and cyanoguanidine by capillary zone electrophoresis and its application in a stability study 下载免费PDF全文
Athiporn Doomkaew Brompoj Prutthiwanasan Leena Suntornsuk 《Journal of separation science》2014,37(13):1687-1693
A capillary zone electrophoresis method was established for stability study of metformin (MET). MET and cyanoguanidine (CGN; a major degradation product) were well separated (with a resolution of 38.9) in 40 mM citrate buffer (pH 6.7) using a fused‐silica capillary with an effective length of 60 cm and an inner diameter of 50 μm, injection at 50 mbar for 5 s at 30°C with an applied voltage of 15 kV and diode array detection at 214 nm. Method validation showed good linearity (r2 > 0.99), precision (%RSDs < 1.98%), and accuracy (%recovery between 98.3 and 100.9%). Limits of detection and quantification were <30 and 100 μg/mL, respectively. The method was robust upon alteration of pH and voltage (%RSDs < 1.99%). Stability profiles of metformin from 11 stress conditions and the degradation kinetics could be established, using the simple capillary zone electrophoresis system. A mechanism for the degradation of MET was also proposed. MET was stable in neutral hydrolysis, but degraded under alkaline hydrolysis and oxidation. Under both conditions, CGN was quantified as the degradation product. An assay of MET in raw material and tablets showed that content of the drugs in all samples met the requirements of pharmacopeias and CGN was not detected. 相似文献
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用N-N二甲基甲酰胺和纳米银对导电玻璃(ITO)进行修饰得到了N-N二甲基甲酰胺/纳米银修饰电极。研究了电极的电化学行为,在pH=6.64的PBS缓冲溶液中,盐酸二甲双胍在0.075~0.2mg/mL浓度范围内与氧化峰电流呈现很好的线性关系,线性方程为y=317.19x+30.076,最低检出限为0.000 7mg/mL,线性相关线性系数R2为0.959 5。平行测量5组数据,其RSD值为0.75%,在盐酸二甲双胍缓释片溶液中5次加标回收率平均值为101%。精密度和准确度的分析结果表明方法可应用于药物中盐酸二甲双胍含量的测定。 相似文献
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Developing imprinted polymer nanoparticles for the selective separation of antidiabetic drugs 下载免费PDF全文
Isma Haq Adnan Mujahid Adeel Afzal Naseer Iqbal Sadia Zafar Bajwa Tajamal Hussain Khurram Shehzad Hadia Ashraf 《Journal of separation science》2015,38(19):3469-3476
In this study, new molecularly imprinted polymer (MIP) nanoparticles are designed for selective recognition of different drugs used for the treatment of type 2 diabetes mellitus, i.e. sitagliptin (SG) and metformin (MF). The SG‐ and MF‐imprinted polymer nanoparticles are synthesized by free‐radical initiated polymerization of the functional monomers: methacrylic acid and methyl methacrylate; and the crosslinker: ethylene glycol dimethacrylate. The surface morphology of resultant MIP nanoparticles is studied by atomic force microscopy. Fourier transform infrared spectra of MIP nanoparticles suggest the presence of reversible, non‐covalent interactions between the template and the polymer. The effect of pH on the rebinding of antidiabetic drugs with SG‐ and MF‐imprinted polymers is investigated to determine the optimal experimental conditions. The molecular recognition characteristics of SG‐ and MF‐imprinted polymers for the respective drug targets are determined at low concentrations of SG (50–150 ppm) and MF (5–100 ppm). In both cases, the MIP nanoparticles exhibit higher binding response compared to non‐imprinted polymers. Furthermore, the MIPs demonstrate high selectivity with four fold higher responses toward imprinted drugs targets, respectively. Recycled MIP nanoparticles retain 90% of their drug‐binding efficiency, which makes them suitable for successive analyses with significantly preserved recognition features. 相似文献
27.
RP-HPLC测定黄连上清片中盐酸小檗碱含量 总被引:2,自引:0,他引:2
用反相高效液相色谱法测定中药复方制剂黄连上清片中有效成分盐酸小檗碱含量。采用Agilent 1100 ODS色谱柱(4.6mm×150mm,5μm),乙腈-0.05mol/L磷酸二氢钠溶液(用磷酸调pH值至3)(30∶70,V/V)为流动相,检测波长为345nm,流速1.0mL/min,柱温25℃。盐酸小檗碱在0.16—4.0μg/mL范围内与峰面积呈良好的线性,r=0.9999,平均加样回收率为98.96%(n=6),RSD=1.09%。该法快速简便,灵敏度和稳定性高,可有效控制黄连上清片的内在质量。 相似文献
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