日立270—50型红外分光光度计简介

<正> 红外分光光度计可记录物质在一定波长区域的红外吸收光谱,根据记录的吸收光谱对被测物质进行定性或定量分析,为确定分子结构,提供丰富、准确的信息,是药学上最常用的重要工具之一。辽宁省药物所新引进一台日立270—50型红外分光光度计,是八十年代产品,基本上具备了当今红外光谱仪进展的新特点。一、该仪器的关键部件检测器有了改进。早期的     

一种使用傅里叶红外光谱仪进行波长测量的新方法

目的开发在药物分析中常用的现有设备的功能,实现一机多用。方法使用Equinox 55傅里叶红外光谱仪,移除自带光源,对某型号多功能红外光谱治疗仪进行红外波段波长测量,用常用的可见光区段光谱照度计对可见光区域光谱进行测量,并对红外光绝对强度的测定进行了讨论。结果该光谱治疗仪工作波长为0.42～2.5μm,所测红外光强度与计量结果基本一致。结论傅里叶红外光谱仪可用于红外光源波长测量。     

串联双电极电化学检测HPLC测定核黄素

在电化学检测液相色谱中已广泛采用双电极检测以提高选择性和灵敏度,利用维生素B_2的可逆电化学反应,本文采用串联双电极还原-氧化检测维生素B_2。使用一实验室装置的伏安分析计,循环伏安法采用三电极的电池系统:玻璃碳工作电极、银-氯化银参比电极和铂辅助电极。色谱系统包括Waters510型泵、U 6 K进样阀、481型可变波长检测器。进样量20μl,检测波长254 nm,流动相流速每分钟     

反相HPLC法测定血清和尿液中普鲁卡因酰胺和其三种代谢产物

本文介绍一种同时测定血清或尿液中普鲁卡因酰胺(PA)和其三种代谢产物〔N乙酰普鲁卡因酰胺(NAPA)、去乙基普鲁卡因酰胺(EDPA)和去乙基N-乙酰普鲁卡因酰胺(DENAPA)的反相高效液相色谱方法。仪器:色谱系统由2010型泵、2050型可变波长紫外检测器、7125型手动注射阀和记录仪组成。4.5×150mm IBM苯基柱,粒度5μm。流速每分钟1.0 ml,柱压80 atm。检测器输出10mV,时间1秒。记录仪纸速每分钟0.25 cm,检测波长270nm。流动相:以0.075 M乙酸盐缓冲液(pH     

替硝唑葡萄糖注射液中替硝唑标示含量测定法的研究

替硝唑葡萄糖注射液是我公司研制的四类新药 ,在试验过程中 ,对替硝唑标示含量的检验方法进行了广泛研究 ,最后认为用紫外分光光度法中的对照品比较法检测替硝唑的标示含量 ,简便可靠 ,可满足生产和检验的需要。1 仪器与检测条件仪器 :ＵＶ - 2 5 0型紫外分光光度计 (日本 ) ,检测波长为 2 77ｎｍ。2 方法与结果2 1检测波长的确定　精密称取替硝唑对照品适量 ,以 0 1ｍｏｌ/ＬＨＣｌ为溶剂 ,制备成每ｍｌ含约16 μｇ的溶液 ,然后在紫外分光光度计上进行紫外扫描 ,波长范围定为 2 0 0— 4 0 0ｎｍ ,结果替硝唑在 2 77ｎｍ波长处有最大吸收…     

海洛因及其盐型的红外光谱分析

目的:探讨红外光谱技术在海洛因及其盐型分析中的作用。方法:采用红外光谱技术对海洛因样品进行谱图采集,并对海洛因及其盐型的红外谱图进行谱图解释和分析。结果:应用红外光谱技术,可以很好地鉴别海洛因及其盐型。结论:红外光谱技术可用于海洛因及其盐型的区分。     

漫反射FT-IR和单晶XRD法研究盐酸林可霉素多晶型

目的：研究盐酸林可霉素2种晶型晶体结构中不同分子构象对其漫反射红外光谱行为的影响。方法：单晶X射线衍射法、傅立叶变换漫反射红外光谱法。结果：盐酸林可霉素2种晶型分属不同晶系及空间群。它们在晶胞中的分子内、分子间氢键与分子构象不同，从而造成其漫反射红外光谱行为的显著差别。结论：可用傅立叶变换红外漫反射光谱法鉴别盐酸林可霉素2种晶型。     

红外光谱法在药物分析中的应用

红外光谱法在化学领域中已得到广泛的应用,对有机化学的发展作出了重要的贡献。红外光谱法现已成为药物分析中不可缺少的工具之一。本文就红外光谱法在控制药品质量(定性鉴别、多晶型的研究以及药品顺反异构体的研究)、制剂研究(制剂中药物的鉴别、含量测     

高效液相色谱法测定风湿骨痛丸中双酯型生物碱的限度

目的建立高效液相色谱法测定风湿骨痛丸中双酯型生物碱的限度。方法供试品采用超声处理法,双酯型生物碱中三种成分通过菲罗门C18被检测,柱温30℃,以乙腈—四氢呋喃—0.1 mol.L-1的乙酸铵溶液(每1 000 mL中加冰醋酸0.5 mL)(12.5∶7.5∶80)为流动相,检测波长230 nm。结果乌头碱、次乌头碱、新乌头碱峰分离度均良好,且无干扰。结论此法准确,重复性好,可用于控制该处方中制川乌、制草乌中双酯型生物碱的限度。     

浅谈红外光谱法定性分析苯巴比妥的一点体会

1红外光谱定性分析的基本原理及特性红外光谱法（IR）是分子吸收光谱的一种。利用物质对红外光区的电磁辐射的选择性吸收来进行结构分析及对各种吸收红外光的化合物的定性和定量分析的方法。一种被测物质的红外光谱记录了其分子的振动,而振动的频率取决于组成原子的量、化学键的强弱和物质内部的结构基团。原子的种类、健力的变化及基团的组合都可以在红外光谱图上表现出来。因此,每一种具有确定化学组成和结构特征的相同物质,都应具有相同的吸收谱带数目、谱带位置、谱带形状和谱带强度的红外光谱。对红外光谱进行剖析,可对物质进行定性分析。     

Physical characterization of solid forms of urapidil

Polymorphic forms of urapidil were prepared by various techniques. Three polymorphic forms were identified and their solid-state properties were characterized by thermal behaviour, X-ray powder diffraction, IR spectra, intrinsic dissolution rates, solution calorimetry and scanning electron microscopy. Solution calorimetry was used to determine each polymorph in mixtures of Forms I and II, with a reproducibility of +/-3 per thousand The stability of the three polymorphic forms was followed over a period of three months under different conditions and it was concluded that Forms I, II and III of urapidil were enantiotropic.     

吲哚拉新药物的多晶型研究——(1)多晶型的制备与鉴别

本文分别选择乙醇、乙醇-水、丙酮、丙酮-水、甲醇、乙腈、丙酮-石油醚、苯、无水乙醚等溶剂,制备了吲哚拉新的多晶型,通过差热分析、红外吸收分光光度法及X射线粉末衍射法等鉴别,确定吲哚拉新药物结晶至少存在三种不同的晶型。     

Polymorphism of spironolactone

Single crystals of two polymorphic and four solvated crystalline forms of spironolactone (C24H32O4S) were obtained using different solvents. The morphology, symmetry, and crystallographic parameters were determined for all crystal forms except for the one obtained from methanol. The stability and transformation of each type of crystal were studied by DSC, TGA, and X-ray diffraction analysis. The structural data of three forms allowed the observation of the change of conformation of the molecules of spironolactone in the three different lattices.     

甲苯咪唑的不同晶型对巴西日本圆线虫驱除效果的研究

甲苯咪唑具有三种不同晶体结构[I(或B)、Ⅱ(或C)、I(或A)型],用大鼠——巴西日本圆线虫模型进行生物鉴定的结果表明,I及Ⅱ型驱虫效果好,I型无驱虫作用。本药混晶(Ⅱ+Ⅲ型)中,Ⅲ型的比例在30％以下,而给药剂量大于250mg/kg/dx3时对驱虫效果无明显影响。三种晶型可以直接或间接互相转换,I型转为Ⅱ型,驱虫效果不变;I型转为Ⅱ型驱虫有效;而Ⅱ型转为I型则丧失驱虫作用。本药的驱虫效果仅与晶型有关,而与制备方法无关。     

Polymorphism and crystal structure of 2R,4S,6-fluoro-2-methyl-spiro[chroman-4,4'-imidazoline]-2',5-dione (M79175)

Two polymorphic forms, alpha and beta, of 2R,4S,6-fluoro-2-methyl-spiro-[chroman-4,4'-imidazoline]-2',5-dione (1, M79175) were studied by X-ray crystallography and solid-state infrared spectroscopy. The molecular and crystal structures of the beta-form were determined by single-crystal X-ray diffraction analysis. The molecules in the beta-form crystal are arranged orderly along the b-axis, and the plate-like moieties (chroman ring) of 1 are stacked by van der Waals forces. The molecular packing structure of each crystalline form was investigated by comparing wave numbers of hydantoin rings from which solid-state infrared photoacoustic spectra (FT-IR-PAS) were obtained. From the FT-IR-PAS data of both forms, it became clear that the hydrogen bond in an alpha-form crystal is stronger than that in the beta-form crystal. The cohesion of the polymorphic crystal system is mainly due to hydrogen bonds and van der Waals forces. Based on the polymorphism of 1, it was clarified that thermodynamic stability depends on the mode of hydrogen bonding, while the enthalpy of fusion results from van der Waals forces.     

Quantitation of crystalline and amorphous forms of anhydrous neotame using 13C CPMAS NMR spectroscopy

Although most drugs are formulated in the crystalline state, amorphous or other crystalline forms are often generated during the formulation process. The presence of other forms can dramatically affect the physical and chemical stability of the drug. The identification and quantitation of different forms of a drug is a significant analytical challenge, especially in a formulated product. The ability of solid-state 13C NMR spectroscopy with cross polarization (CP) and magic-angle spinning (MAS) to quantify the amounts of three of the multiple crystalline and amorphous forms of the artificial sweetener neotame is described. It was possible to quantify, in a mixture of two anhydrous polymorphic forms of neotame, the amount of each polymorph within 1-2%. In mixtures of amorphous and crystalline forms of neotame, the amorphous content could be determined within 5%. It was found that the crystalline standards that were used to prepare the mixtures were not pure crystalline forms, but rather a mixture of crystalline and amorphous forms. The effect of amorphous content in the crystalline standards on the overall quantitation of the two crystalline polymorphic forms is discussed. The importance of differences in relaxation parameters and CP efficiencies on quantifying mixtures of different forms using solid-state NMR spectroscopy is also addressed.     

Characterizing the conversion kinetics of carbamazepine polymorphs to the dihydrate in aqueous suspension using Raman spectroscopy

In an aqueous environment, polymorphic forms I-III of carbamazepine all convert to the dihydrate. This study investigated the conversion of each polymorphic form individually and of a mixture of forms III and I to the dihydrate. Two batches of form I with different crystal morphology were used. Samples were dispersed independently in water at 23+/-1 degrees C and recovered at various timepoints varying from 10 to 210 min. Scanning electron microscopy, X-ray powder diffraction and Raman spectroscopy were used to characterize the initial polymorphic forms and the recovered samples after 210 min. Raman spectroscopy combined with partial least squares analysis was used to generate quantitative models of binary and ternary mixtures of the different polymorphic forms with the dihydrate. On the basis of these models the conversion kinetics of the polymorphic forms I-III were characterized. First-order kinetics with an unconverted portion were used to model the data (R2> or =0.95). The unconverted portions ranged from 16 to 51% after dispersion for 210 min. The conversion kinetics were similar between polymorphic forms with comparable crystal morphology, but differed significantly between batches of the same polymorph (form I) with different crystal morphology. Furthermore, the conversion of forms III and I in the aqueous suspension was not influenced by the presence of the other polymorph when dispersed together.     

C型甲苯咪唑的红外光谱定量测定

本文用红外光谱法测定了甲苯咪唑中晶型C的含量。取高铁氰化钾细粉(6mg)为内标物,与样品细粉(30mg)在0.25ml液体石蜡中仔细研磨均匀。将糊状物放入0.1mm铅片隔开的KBr窗片之间,分别于800～850cm^-1和2050～2150cm^-1以吸收度的方式扫描谱图。最后以834和842cm^-1,2114和2140cm^-1吸收度之差按内标法计算甲苯咪唑C型晶型的百分含量。该法对甲苯咪唑原料和片剂都适用,操作简便、专属性高,结果满意。     

Assessment of the solid-state composition of an active salicylanilide compound by FT-Raman spectroscopy

A biologically active salicylanilide compound currently appears in three known solid-state forms: polymorph I (Pol I), polymorph II (Pol II) and the amorphous form (Amorph). The obtained FT-Raman spectra revealed several regions of interest (ROIs) qualitatively distinguishing the different forms, allowing samples with an unknown polymorphic composition to be quantitatively analysed by FT-Raman spectroscopy. The Markov-transformed peak areas of the Raman-bands in the ROIs from the samples were determined and compared with the transformed peak areas obtained for the reference solid-state forms. A constrainted linear regression model estimated the contribution of each reference to the different samples. The applicability of this approach was demonstrated by analysing commercially available batches.     

The effect of crystal forms of some barbiturates on their pharmaceutical properties. Part 1: Phenobarbitone.

Up to 13 polymorphic forms of phenobarbitone have been reported in the literature. By melting the commercial sample and cooling under specified controlled conditions, three polymorphic forms II, II, XII, and a mixed form of II and III were obtained. The interconversion of the different forms was studied by special procedures including suspension in water, heating, and heavy dry grinding. The hydrated form XIII and a new hydrated one, designated XIV, were produced by suspending different other forms in water. Heating was found to affect transformation from any form to form I. IR spectroscopy and hot stage microscopy were used for the identification of the different polymorphic forms. Initial dissolution rate studies were carried out on only five forms. The dissolution rate constants were in the following decreasing order: II greater than III greater than I greater than XIV greater than XIII. Form II was found to dissolve at a rate constant about twice that of both hydrated forms.