蒙药草乌花及其提取物化学成分的红外光谱法整体结构解析

采用傅立叶变换红外光谱法并借助于二阶导数谱以及二维相关红外光谱(2D-FTIR)研究了蒙药草乌花原药材及不同溶剂提取物(依次采用乙醚,乙醇和水提取)所含化学成分的红外谱图整体变化规律.结果显示:在草乌花原药材中具有明显的多糖类化合物的红外特征吸收峰,证明该药材中含有大量多糖类成分.草乌花药材乙醚和醇提物的红外光谱较相似...     

溪黄草及其不同提取物的红外光谱研究

采用一维红外光谱、二阶导数谱和二维相关红外光谱对溪黄草原药材及其不同溶剂提取物进行了红外光谱研究。结果表明:溪黄草原药材中含有酯类、芳香类和糖苷类等物质,溪黄草水提物中主要为糖类物质,乙醇提取物中主要为黄酮类物质,石油醚提取物中主要为酯类物质。红外光谱能够快速、简便地提供中药及其提取物中主要化学成分的宏观信息,从而为后续的化学成分分析和中药提取分离方法的改进和优化提供有效参考。     

不同产地黄芪的红外光谱鉴别研究

采用红外光谱、二阶导数红外光谱和二维相关红外光谱,对四种不同产地的黄芪原药材进行了鉴别研究。结果表明:不同产地黄芪的红外光谱和二阶导数红外谱具有一定的相似度,与淀粉的红外谱图比对,4个不同产地的黄芪均含有淀粉,其中陕西绥德产黄芪的淀粉含量比其它3个产地黄芪的都要高。山西浑源和山西天镇产黄芪谱图的1 510、1 425cm-1木质素特征峰比内蒙古固阳和陕西绥德产黄芪的更为明显,说明前二者产黄芪中木质素含量高于后二者产黄芪。在二维相关红外谱图上,根据4个产地黄芪的相对峰强度的差异,可进行产地的鉴别。研究结果表明对于不同产地黄芪的鉴别,红外三级鉴定法是一种快速有效的新方法。     

松杉灵芝不同部位的红外光谱分析研究

采用红外光谱三级鉴定法对松杉灵芝菌盖、表皮、菌柄、子实体不同部位的红外光谱图进行了整体分析。结果表明:松杉灵芝的各部位均含萜类、甾醇类、氨基酸、多肽、蛋白质和糖苷类等物质。在松杉灵芝的一维红外光谱中,菌盖的1 649cm-1峰的相对强度明显比表皮、菌柄和子实体强,说明菌盖中所含的氨基酸、多肽、蛋白质物质的量比其它部位高;在二阶导数谱中,四者在1 720~1 600cm-1范围内峰形差别较大,进一步说明松杉灵芝不同部位所含氨基酸、多肽、蛋白质物质不一致;而二维相关红外光谱中,各部位自动峰的数目、峰位置和峰相对强度都有所不同,可推断松杉灵芝各部位本身所含的糖苷类物质是不一致的。     

红外光谱法分析酵母蛋白质的二级结构

采用红外光谱法分析了酵母蛋白质的二级结构。测定了不同温度下酵母酰胺Ⅲ带的一维红外光谱、二阶导数红外光谱及去卷积红外光谱。结果表明:随着测量温度的升高,酵母中的蛋白质α-螺旋结构的红外吸收强度降低;而β-转角结构、无规卷曲结构和β-折叠结构红外吸收强度均有所增加。还研究了酵母酰胺Ⅲ带的二维红外光谱,以确定酵母中蛋白质红外吸收强度的变化次序,进一步证明了酵母蛋白质的β-折叠结构的热不稳定性。     

党参及其水提取物的红外光谱研究

采用傅里叶变换红外光谱法,并结合二阶导数红外光谱法,研究了党参原药材及其水提取物所含化学成分的红外谱图整体变化规律。结果表明,党参水提取物中主要为糖类成分,含有935、868、817、779cm-1等一系列糖环的振动吸收峰,通过谱峰的指认可以判定党参水提取物中主要含有甘露糖、果糖和葡萄糖等单糖;水提取物药渣中则是提取后剩余的淀粉、纤维素、木质素等原药材的基体成分和一些不易溶于水的酯类、酮类和芳香类成分。     

变温傅里叶红外光谱技术研究硬脂酸C-H伸缩振动

采用傅里叶红外光谱技术研究了温度对于硬脂酸C-H伸缩振动、分子脂肪链构象改变和分子间作用力的影响。运用变温红外技术在293~393K范围内,分别测定了硬脂酸C-H的一维红外光谱、二阶导数红外光谱、四阶导数红外光谱和去卷积红外光谱。结果表明:1在293~333K范围内,一维红外光谱中2 965,2 870cm-1附近的弱吸收谱带分别归属于甲基的不对称伸缩振动模式νas(-CH3)和对称伸缩振动模式νs(-CH3),相应的导数光谱及去卷积红外光谱能提高一维红外谱的分辨率;2在293~333K范围内,硬脂酸脂肪链处于全反式构象,在348~353K范围内,硬脂酸分子脂肪链构象由全反式构象向无序构象转变;3随着测量温度的升高,硬脂酸分子间的作用力不断降低。     

变温傅里叶红外光谱技术研究硬脂酸结构及相变机理

采用傅里叶红外光谱法研究了温度对于硬脂酸分子结构影响。通过变温红外技术在293~393K范围内,分别测定了硬脂酸羰基的傅里叶红外光谱、二阶导数红外光谱及去卷积红外光谱。结果表明,硬脂酸主要存在反式二聚体1、顺式二聚体2、开环二聚体3及单体4等4种结构。     

红外二阶导数指纹图谱用于紫花地丁药材的产地分类

建立了紫花地丁药材的红外二阶导数指纹图谱。采用傅里叶变换-红外光谱法测定10个不同产地紫花地丁试样的红外光谱,红外分辨率为8 cm-1,扫描范围为4 000~400 cm-1,利用二阶导数重构指纹图谱后,进行系统聚类分析和Fisher′s判别分析。结果表明所建立的方法能够能有效地对样品产地进行预测,可为紫花地丁药材质量控制提供一种简便、有效的手段。     

二维红外光谱法分析纤维素

采用二维红外光谱法分析纤维素。在293~393K范围内,分别测定脱脂棉纤维的一维红外光谱、二阶导数红外光谱和去卷积红外光谱。结果表明:脱脂棉纤维中的α-纤维素在559cm-1有一个的红外特征吸收峰,β-纤维素在893,1 206,1 235cm-1处有红外特征吸收峰;随测定温度的升高,559cm-1处红外吸收强度降低,893,1 206,1 235cm-1处红外吸收强度增加。进一步采用二维红外光谱研究温度对于脱脂棉纤维结构的影响,结果表明:随测定温度的升高,脱脂棉纤维红外特征吸收峰强度增加的顺序为893cm-11 235cm-11 206cm-1559cm-1。     

二维相关红外光谱法与阿胶的真伪鉴别

采用傅里叶变换红外光谱法(FT-IR)和二维相关红外光谱技术(2D-IR)对几种阿胶进行了真伪鉴别。实验结果表明,伪品阿胶和黄明胶与标本东阿阿胶的谱图较为相似,尤其是黄明胶与阿胶极其相似,仅仅在1648cm^-1的酰胺I带的吸收峰和东阿阿胶有9个波数的区别;不同批次和厂家的正品阿胶的红外光谱图更为相似,难以区分开,借助于二维相关红外光谱法,获取了物质的微观结构信息,提高了谱图的分辨率,几种真品阿胶得到了直观有效的鉴别。     

Noninvasive Surface Detection of Papillary Thyroid Carcinoma by Fourier Transform Infrared Spectroscopy

Previously Fourier transform infrared(FTIR) spectroscopy has been applied to detecting thyroid cancer during operations and to discriminating cervical metastatic ones from non-metastatic lymph nodes. This study explored the possibility of establishing a sensitive, accurate and noninvasive screen or diagnosis by preoperative FTIR spectroscopy. 111 patients undergone a thyroid operation and 50 healthy volunteers were enrolled in the study. The FTIR spectra were obtained by two mid-infrared optical fibers with an attenuated total reflectance(ATR) probe closely contacting the subjects' skin on the thyroid nodules. The FTIR spectra obtained from normal thyroid, nodular goiter(NG) and papillary thyroid carcinoma(PTC) patients were compared. A Fisher's discriminant analysis was created based on these data. There were 41 PTC patients and 70 NG patients according to their histopathological examinations. A total of 23(of 39) parameters were statistically different among the three groups(P<0.05). The F₁₃₀₀ and F₁₀₈₀ parameters were significantly different between the three groups. In total, 9 out of 39 FTIR parameters were selected as independent factors by the Wilks' lambda stepwise discriminant analysis. The discrimination accuracy of papillary thyroid carcinoma in the three groups was 88.8%. Surface detection of PTC by FTIR spectroscopy is feasible. FTIR spectroscopy can be used for rapid and noninvasive PTC screen and auxiliary diagnosis.     

HATR-FTIR-排序法识别中药材紫花地丁及其伪品的研究

采用水平衰减全反射傅里叶变换红外光谱(HATR-FTIR)法测定了紫花地丁及其伪品如白花地丁、犁头草、辽宁堇菜及匍伏堇的根木质部和茎外表皮部的傅里叶变换红外光谱,采用主成分分析法(PCA)比较了正伪品之间的差异程度。结果表明：基于傅里叶变换红外光谱的主成分分析在反映同科同属不同种植物化学组成差异程度上具有应用价值。     

傅里叶变换红外光谱和核磁共振法对土壤中腐殖酸的表征

采用氢氧化钠碱提法提取和纯化了我国４种典型土壤中腐殖酸,分别用元素分析、傅里叶变换红外光谱（ＦＴＩＲ）、固仿核磁共振（ＮＭＲ）等方法对提取腐殖酸进行了表征。结果表明,４种土壤中腐殖酸原ＦＴＩＲ图谱相似,含有相同类型的官能团。对ＮＭＲ不同化学位移域的谱峰积分获得４种土壤腐殖酸的各组成比例,组成中以烷氧基Ｃ的含量最高,脂类Ｃ略高于芳香Ｃ含量。     

中药配方颗粒红外光谱法的快速鉴别

采用红外光谱法对中药配方颗粒及其辅料进行了鉴别研究。结果表明：不同生产厂商的配方颗粒中所添加的辅料类型及用量有较大差别；不同种的配方颗粒在辅料含量较低的情况下有较明显的指纹性，而辅料含量较高时，采用差谱技术可以提高谱图的指纹性，达到中药配方颗粒--鉴别的目的。该法简便、快速、可靠，是中药配方颗粒宏观质控的一个强有力的手段。     

中药配方颗粒红外指纹图谱研究

采用傅里叶变换红外光谱(FTIR)技术分析鉴别了350种中药配方颗粒红外指纹图谱的结构特征。结果表明，借助于各种药用植物和动物配方颗粒的FTIR指纹图谱的差别可进行快速分类鉴别；根据配方颗粒与中药原药材谱图之间的相关性，以及中药材经过炮制、加热、水提处理后，配方颗粒与原药材之间在谱图上所代表的化学成分上的异同可以进行中药配方颗粒的质量控制；凭借不同炮制方法与未经炮制处理的配方颗粒间FTIR谱图的差别，可以进一步分析炮制后配方颗粒化学成分的变化，不同炮制方法对配方颗粒化学成分的影响；对于不同厂家的配方颗粒及同一厂家不同生产批号的配方颗粒也进行了较系统的分析研究。方法快速，简便，专属性强，不需对样品进行分离提取。     

36种灵芝产品傅里叶变换红外光谱快速鉴别研究

利用傅里叶变换红外光谱法（FTIR）无损快速鉴别了36种灵芝类产品。灵芝、孢子粉和菌丝体的红外谱图差别较显著;不同厂家所生产的灵芝产品由于所选用灵芝的产地不同、所用辅料的种类以及辅料所添加的多少不同,均引起了谱图的相对峰强度和波数位置的改变。结果表明：36种灵芝产品均可以根据红外的特征谱图进行分类鉴别。该方法快速、不需对灵芝产品进行分离提取。     

Detection of Cholangiocarcinoma with Fourier Transform Infrared Spectroscopy and Radial Basis Function Neural Network Classification

The aim of this study was to explore the possibility of applying Fourier transform infrared(FTIR) spectroscopy as a medical diagnostic tool based on a neural network classifier for detecting and classifying cholangiocarcinoma. A total of 51 cases of bile duct tissues were obtained and later characterized by FTIR spectroscopy prior to pathological diagnosis. The criteria for classification included 30 parameters for each FTIR spectra, including peak position(P), intensity(I) and full width at half-maximum(FWHM), were measured, calculated and subsequently compared against the normal and cancer groups. The FTIR spectra were classified by the radial basis function(RBF) network model. For establishing the RBF, 23 cases were used to train the RBF classifier, and 28 cases were applied to validate the model. Using the RFB model, nine parameters were observed to be pronouncedly different between cancerous and normal tissue, including I₁₆₄₀, I₁₅₅₀, I₁₄₆₀, I₁₄₀₀, I₁₂₅₀, I₁₁₂₀, I₁₀₈₀, I₁₀₄₀ and P₁₀₄₀. In the RBF training classification, the accuracy, sensitivity, and specificity of diagnosis were 82.6%, 80.0%, and 84.6%, respectively. While validating the classification, the accuracy, sensitivity, and specificity of diagnosis were 78.6%, 75.0%, and 81.2%, respectively. The results suggest that FTIR spectroscopy combined with neural network classifier could be applied as a medical diagnostic tool in cholangiocarcinoma diagnosis.     

甲状腺癌微转移淋巴结的红外光谱检测

采用衰减全反射(ATR)探头和傅里叶变换红外光谱(FTIR)仪测定了新鲜离体的甲状腺癌微转移颈部淋巴结(16枚)和非转移性淋巴结(16枚)的FTIR光谱, 配对比较了两组光谱13个谱带的峰位、相对峰强及半高宽等38个FTIR参数, 明确了甲状腺癌微转移淋巴结的光谱特征.结果表明, 与非转移性淋巴结相比, 微转移淋巴结光谱中与蛋白、脂质、糖类和核酸相关的谱带均发生了明显变化:与蛋白质相关的谱带的相对峰强I₃₂₈₀/I₁₄₆₀和I₁₆₄₀/I₁₄₆₀显著升高, 半高宽F₁₆₄₀显著增宽, 而F₁₅₄₆则变窄; 与脂类相关的相对峰强I₁₄₀₀/I₁₄₆₀明显增高; 与糖类相关的1165 cm^-1处谱带的相对峰强I₁₁₆₅/I₁₄₆₀显著降低; 与核酸相关的1240 cm^-1处谱带的相对峰强I₁₂₄₀/I₁₄₆₀显著升高.结果表明, FTIR能够检测出甲状腺癌的微转移淋巴结, 可能应用于甲状腺癌病人的精准手术治疗.     

Polarization Dependent Time-Resolved Infrared Spectroscopy and Its Applications

Polarization dependent time-resolved infrared (TRIR) spectroscopy has proven to be a useful technique to study the structural dynamics in a photochemical process. The angular information of transient species is obtainable in this measurement, which makes it a valuable technique for the investigation of electron distribution, molecular structure, and conformational dynamics. In this review, we briefly introduce the principles and applications of polarization dependent TRIR spectroscopy. We mainly focused on the following topics: (i) an overview of TRIR spectroscopy, (ii) principles of TRIR spectroscopy and its advantages compared to the other ultrafast techniques, (iii) examples that use polarization dependent TRIR spectroscopy to probe a variety of chemical and dynamical phenomena including protein conformational dynamics, excited state electron localization, and photoisomerization, (iv) the limitations and prospects of TRIR spectroscopy.