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151.
贺美莲  郭常川  冷佳薇  张迅杰  咸瑞卿  巩丽萍  石峰  姜玮 《色谱》2018,36(11):1099-1104
采用超高效液相色谱-串联质谱(UHPLC-MS/MS)技术,建立了快速、简单、灵敏的测定人血浆中盐酸氨溴索含量的方法,并用于盐酸氨溴索人体生物等效性预试验研究。取50 μL血浆样品,采用蛋白沉淀法处理,以盐酸氨溴索-d5为内标。采用Waters XBridge BEH C18色谱柱(50 mm×2.1 mm,2.5 μm),以0.1%(v/v)甲酸水-含0.1%(v/v)甲酸的甲醇为流动相,在0.4 mL/min流速下进行梯度洗脱。采用电喷雾电离(ESI)源以正离子模式进行MRM检测。结果显示,盐酸氨溴索在2~400 ng/mL范围内线性关系良好,相关系数(r)为0.998,准确度为97.1%~108.7%,精密度为1.0%~5.6%。将该方法用于6名健康受试者口服盐酸氨溴索受试制剂和参比制剂30 mg后血药浓度的测定,结果显示二者相对生物利用度为(102.3±14.8)%,血药浓度-时间曲线下面积(AUC0-t、AUC0-∞)和最大血药浓度(Cmax)的90%置信区间均在80.0%~125.0%范围内,两种制剂生物等效。  相似文献   
152.
Novel glucosamine hydrochloride functionalized water‐soluble conjugated polyfluorene was easily synthesized through Cu(I)‐catalyzed azide/alkyne “click” ligation and Suzuki coupling polymerization. The water‐solubility and biocompatibility of the polymer were improved after grafting glucosamine hydrochloride to the side chains of the conjugated polymer. As a fluorescent model system of chitosan, its interaction with single‐stranded DNA was studied by spectrofluorometric titration.

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153.
盐酸曲马多离子选择性电极的研制与应用   总被引:4,自引:1,他引:3  
介绍了盐酸曲马多离子选择性电极的制备,特性以及在药物分析方面的应用。综合考虑活性物质的含量和增塑剂种类及含量的影响,选择了以盐酸曲马多—四苯硼钠缔合物为活性物质,以DOP为增塑剂的电极体系。该电极在5×10-5~1×10-2mol/L范围内表现能斯特响应,斜率为57.1mV/pC,检测下限为1×10-5mol/L。电极对多种异质离子表现良好的选择性。运用电位法测定药物中的盐酸曲马多,回收率为94.9%~106.0%。  相似文献   
154.
在pH=1.2的Clark Lubs缓冲溶液条件下,曙红B与盐酸洛美沙星复合物的最大吸收峰位于535nm,比曙红B本身红移30nm,复合物的表观摩尔吸光系数为5.82×103L·mol-1·cm-1。方法的线性范围为10~40mg·L-1,检出限为2.2mg·L-1。实验考察了反应条件的影响,初步讨论了反应机理。  相似文献   
155.
冉林松  程新路 《结构化学》2009,28(3):377-380
In the present paper, the electronic band structure, density of states (DOS), and projected density of states (PDOS) analysis of thiocarbamide hydrochloride are reported. Calculations of the electronic properties have been carried out on the basis of fully self-consistent pseudopotential method using DFT. The results show that near the Fermi level, more prominent densities of states are seen between -8 eV and -6 eV in the valence band mainly due to the Cl-3p, N-2p and S-3p orbitals.  相似文献   
156.
流动注射光度法测定药物中的盐酸氯丙嗪   总被引:1,自引:0,他引:1  
在pH 4.04的HAc-NaAc缓冲液中, 刚果红与盐酸氯丙嗪在室温下迅速结合生成缔合物, 且缔合物在480 nm处有最大吸收. 基于此建立了流动注射光度法测定药物中盐酸氯丙嗪的含量. 方法线性范围为0.25~50.0 μg/mL, 检出限为0.082 μg/mL, 测定频率达80次/h.  相似文献   
157.
以L-半胱氨酸甲酯盐酸盐为起始原料,经4步反应合成了(R)-2-甲基半胱氨酸盐酸盐.在关键中间体(2R, 4R)-2-叔丁基-3-甲酰基-4-甲基-1,3-噻唑烷-4-甲酸甲酯(4)的合成中,采用Self-regeneration of stereocenters原理,用六甲基二硅胺钠取代文献方法中的二异丙基胺基锂,4的收率由文献的56%提高至90%.化合物的结构经1H NMR和MS表征.  相似文献   
158.
A simple isocratic reversed-phase high-performance liquid chromatographic method (RP-HPLC) was developed for the simultaneous determination of buprenorphine hydrochloride, naloxone hydrochloride dihydrate and its major impurity, noroxymorphone, in pharmaceutical tablets. The chromatographic separation was achieved with 10 mmol L−1 potassium phosphate buffer adjusted to pH 6.0 with orthophosphoric acid and acetonitrile (17:83, v/v) as mobile phase, a C-18 column, Perfectsil Target ODS3 (150 mm × 4.6 mm i.d., 5 μm) kept at 35 °C and UV detection at 210 nm. The compounds were eluted isocratically at a flow rate of 1.0 mL min−1. The average retention times for naloxone, noroxymorphone and buprenorphine were 2.4, 3.8 and 8.1 min, respectively. The method was validated according to the ICH guidelines. The validation characteristics included accuracy, precision, linearity, range, specificity, limit of quantitation and robustness. The calibration curves were linear (r > 0.996) over the concentration range 0.22-220 μg mL−1 for buprenorphine hydrochloride and 0.1-100 μg mL−1 for naloxone hydrochloride dihydrate and noroxymorphone. The recoveries for all three compounds were above 96%. No spectral or chromatographic interferences from the tablet excipients were found. This method is rapid and simple, does not require any sample preparation and is suitable for routine quality control analyses.  相似文献   
159.
Detection of drug vapors and volatile products of their decomposition is an important, and sometimes the only way to determine the presence of illegal drug traces at the surface of mail items, documents, hands and banknotes. This paper gives the results of experimental studies on the effect of UV irradiation on the sensitivity of a vapor phase detection of cocaine of different origin by a technology of ion mobility increment spectrometry (IMIS). It is shown that the influence of UV irradiation on the surface of cocaine hydrochloride and crack increases the amplitude of IMIS signals by about eight times. We analyzed ions emerged by photolysis of tested cocaine samples using mass-spectrometry with atmospheric pressure ionization (API-MS). The assumption is made about structural formula of volatile products of photolysis of crack and cocaine hydrochloride. By the results of API-MS and IMIS studies on photolysis of cocaine samples it is assumed that compound C10H15NO3 with a molecular weight of 197 amu and ecgonidine methyl ester with a molecular weight of 181 amu are responsible for the increase of an amplitude of IMIS signals upon UV irradiation of samples of crack and cocaine hydrochloride.  相似文献   
160.
An HPLC method for quantitative determination of adrenaline hydrochloride injection and noradrenaline bitartrate injection was established and validated with a substitute for the reference substance.Phenylephrine hydrochloride was selected as the substitute for the reference substance of adrenaline and noradrenaline bitartrate.The correction factor of phenylephrine hydrochloride with respect to the reference substance of adrenaline and noradrenaline bitartrate was determined under defined conditions.Adrenal...  相似文献   
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