Quantitative analysis of bucillamine and its pharmaceutical formulation using FT-IR spectroscopy

A Fourier transform infrared (FT-IR) spectrometric method was developed for the rapid, direct measurement of bucillamine. Conventional KBr-spectra and DRIFTS spectra were compared for best determination of active substance in its tablet formulation. Two chemometric approaches, partial least squares (PLS) and principal component regression (PCR+) methods were used in data processing. Similar results were obtained with both chemometric methods.     

Rapid identification of nicotine in electronic cigarette liquids based on surface-enhanced Raman scattering

Nicotine-containing electronic cigarette liquid (e-liquid) is prohibited in many countries, creating requirements for rapid detection approaches for on-site inspection or screening for large amounts of samples. Here, we demonstrate a simple way to identify nicotine using surface-enhanced Raman scattering (SERS) with substrates made of silver nanoparticle arrays imbedded in anodic aluminum oxide nanochannels (Ag/AAO). Compared with the reported colloidal nanoparticle-based SERS, that required serial dilutions to enable colloid aggregation in the viscous e-liquid, a small amount of undiluted e-liquid sample can be directly added onto our solid-phase Ag/AAO substrate without any pre-treatment. The sensitivity of our SERS measurements is 2–3 orders of magnitude higher than that required for identification of nicotine in e-liquid, which is typically around 1000–18,000 ppm. Using such nanoparticle array-based SERS, we have tested 22 commercially available e-liquid products, using the corresponding gas chromatography-mass spectrometry (GC–MS) reports as the reference. The SERS measurements were done within one hour and successfully identified 20 samples. Only 2 samples showed SERS interference from ingredients that were not suitable for SERS analysis.     

人参、红参、西洋参3种配方颗粒的傅里叶变换红外光谱快速鉴别方法

目的 建立人参、红参、西洋参3种配方颗粒的傅里叶变换红外光谱快速鉴别方法。方法 采用红外光谱及其二阶导数光谱、二维相关光谱,分析不同配方颗粒的红外光谱特征。结果 傅里叶变换红外光谱能够从整体上反映化学成分的不同情况,二阶导数光谱和二维相关光谱在800~1800 cm^-1能够对不同配方颗粒进行不同程度的区分,二维相关光谱的区分效果明显。结论 通过综合比较傅里叶变换红外光谱、二阶导数光谱和二维相关光谱,可以准确、快速鉴别人参、红参、西洋参3种配方颗粒。     

纸基-表面增强拉曼光谱法快速鉴别染色南五味子药材

目的 采用纸基-表面增强拉曼光谱法(SERS)对染色南五味子进行快速鉴别。方法 选用浸泡法制备的银胶纸作为SERS基底,擦拭经乙醇-水溶液润湿的南五味子,银胶纸立即进行SERS检测;先后对银溶胶的浓缩倍数、银胶纸的SERS增强效果及稳定性等因素进行考察。结果 成功鉴别低浓度酸性红、赤藓红染色的南五味子。结论 纸基-SERS法可实现非法染色南五味子的快速、准确、无损的鉴别,有望应用于快检领域。     

Raman spectroscopy using plasmonic and carbon-based nanoparticles for cancer detection,diagnosis, and treatment guidance. Part 2: Treatment

Raman spectroscopy and surface-enhanced raman scattering (SERS) have the potential to improve the detection and monitoring of various diseases, particularly cancer, with or without the support of multifunctional active nanosystems. This review is focused on the recent advances that have made Raman a major tool for treatment guidance for surgical tumor resection or for analytical monitoring of various therapies, such as photodynamic therapy, photothermal therapy, and drug delivery. The potential of Raman spectroscopy and nanosytems to further improve cancer treatments is also discussed.     

Study of flavonoids/beta-cyclodextrins inclusion complexes by NMR,FT-IR,DSC, X-ray investigation

Flavonoids are natural substances with a lot of biological activities, including the antioxidant one. Their use in pharmaceutical field is, however, limited by their aqueous insolubility. As the formation of the inclusion complexes can improve their solubility in water, the flavonoids hesperetin, hesperidin, naringenin and naringin have been complexed with β-cyclodextrin (β-CD) by the coprecipitation method and studied in solution and in solid state by NMR, FT-IR, differential scanning calorimetry and X-ray techniques. The effects of complexation on the chemical shifts of the internal and external protons of β-CD in the presence of each flavonoid were observed.     

Raman spectroscopy using plasmonic and carbon-based nanoparticles for cancer detection,diagnosis, and treatment guidance.Part 1: Diagnosis

Optical techniques, including Raman, photothermal and photoacoustic microscopy and spectroscopy, have been intensively explored for the sensitive and accurate detection of various diseases. Rapid advances in lasers, photodetectors, and nanotechnology have led to the development of Raman spectroscopy, particularly surface-enhanced Raman scattering (SERS), as a promising imaging modality that can help diagnose many diseases. This review focuses on the major recent advances in Raman spectroscopy and SERS-enhancing contrast nanoagents, as well as their potential to transition from a proof-of-concept approach to a cancer detection tool in vitro and in vivo.     

偏最小二乘法用于近红外漫反射光谱快速测定异福片

目的:采用近红外光谱技术,建立一种快速测定异福片中利福平和异烟肼含量的方法。方法:将光谱分别进行卷积平滑、一阶导数、二阶导数预处理,应用偏最小二乘法(PLS)建立定量分析模型,以校正集的交互验证均方根误差(RMSECV)及相关系数(r)为优化参数,选择最佳预处理方法和波长范围。通过留一交互验证法,以预测残差平方和(PRESS)为优化参数,选择最适主因子数。结果:校正集样品利福平和异烟肼的 r 分别为0.9940和0.9910,RMSECV 分别为0.00764和0.00445。对预测集样品利福平和异烟肼的预测均方根误差(RMSEP)分别为0.00397和0.00383;平均加样回收率分别为100.88%和100.87%;重复性试验 RSD 分别为0.672%和1.08%。结论:结果表明该方法预测精度高,且具有方便快捷、非破坏、无污染、可在线检测、重复性好等优点,可作为异福片原位质量检测和在线质量监控的方法予以推广。     

Rapid screening of antioxidants in pharmaceutical formulation development using cyclic voltammetry--potential and limitations

Cyclic voltammetry (CV) is a unique technique for the electrochemical characterization of compounds by providing their oxidation/reduction potentials. This technique is widely used in evaluating antioxidants in the oil, food, diagnostic and agricultural industries; however, CV is rarely used in the development of pharmaceutical formulations. This review briefly describes the basic principles of CV and its application in other industries along with the potential and limitations of CV in the rapid evaluation of antioxidants in pharmaceutical formulations. An extensive survey of the literature shows that there is a good correlation between the oxidation potentials of various antioxidants and their antioxidant efficiency. In conclusion, CV should be useful in the development of pharmaceutical formulations where a small group of the preferred antioxidants is rapidly identified. This small group of the most preferred antioxidants can then be employed in a conventional drug stability study thereby providing a rapid approach for the selection of the most suitable antioxidant for a pharmaceutical formulation.     

A Raman spectroscopic study of the diclofenac sodium–β-cyclodextrin interaction

The inclusion complex of diclofenac sodium (DCFNa) and β-cyclodextrin (βCD) was prepared and analyzed by using Raman and SERS spectroscopy. The interaction between DCFNa and βCD molecules was evidenced by monitoring the change in the peak positions and the widths of some guest molecule bands relative to those observed in the spectra of the free compound and 1:1 DCFNa–βCD physical mixture. Raman data have shown that the interaction between the guest and host molecules in the 1:1 DCFNa–βCD complex is maintained both through the dichlorophenyl ring and the phenylacetate group. SER spectra revealed that depending on the pH value of the solution different isomeric forms of the 1:1 guest–host complex are preferentially adsorbed on the silver surface via the nonbonding electrons of the oxygen atom. The orientation of the adsorbed species with respect to the metal surface was also elucidated.     

The use of FT-IR for the determination of stratum corneum hydration in vitro and in vivo

Measurement of the water content of stratum corneum plays an important role in physiological and therapeutic inquiries in dermatology. There are many techniques available for non-invasive determination of skin hydration such as measurement of electrical, mechanical, thermal and spectroscopic properties of the skin. Most techniques, however, suffer from the fact that they do not employ a direct measurement of water content rather a property caused by skin hydration. Recently, Potts et al., (Arch. Derm. Res. 277, 489–495, 1985) developed an FT-IR method for the determination of water content of the skin both in vitro and in vivo. The method employed attenuated total reflectance infrared (ATR-IR) to measure a weak OH stretch formed by the presence of water at 2100 cm⁻¹. This absorbance is distant from interferences due to skin and most topically applied substances and therefore may be used in the quantitation of skin water content (hydration). This report describes the use of this technique in an investigation into the effect of occlusion on the water content of the skin. Method development and validation employing an in vitro system is also discussed.     

Study on similar traditional Chinese medicines Cornu Cervi Pantotrichum, Cornu Cervi and Cornu Cervi Degelatinatum by FT-IR and 2D-IR correlation spectroscopy

As complicated mixture systems, traditional Chinese medicines (TCM) are very difficult to identify and discriminate, especially for the drug samples have the same source. Therefore, finding a rapid and effective identification method for the similar TCM is the most pressing task in TCM research. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative spectra and two-dimensional correlation infrared spectroscopy (2D-IR), were applied to studying and identifying three very similar traditional Chinese animal drugs Cornu Cervi Pantotrichum (CCP), Cornu Cervi (CC) and Cornu Cervi Degelatinatum (CCD). On the basis of the different FT-IR and 2D-IR spectra ratios of amide I bands, amide II bands and Ca₃(PO₄)₂, three similar animal drugs of the same source were successfully identified and discriminated. Then the FT-IR spectra data of total 30 samples, comprising 10 samples each of above three drugs, were obtained and analyzed with the soft independent modeling of class analogy (SIMCA) pattern recognition technique. The result showed that the three kinds of drug samples located in three different clusters separately. As a result, it was demonstrated that the macroscopic IR fingerprint method could discriminate the three similar TCM, CCP, CC and CCD, rapidly, effectively and non-destructively.     

Synthesis and activity of partial retro-inverso analogs of the antimetastatic laminin-derived peptide,YIGSR-NH2

This paper describes the synthesis and biological evaluation of six partial retro-inverso peptidomimetic analogs of YIGSR-NH₂, a synthetic peptide from the β1 chain of laminin, which has antimetastatic activity. The intent was to improve the antimetastatic potency of YIGSR-NH₂ by limiting the in vivo enzymatic degradation through the incorporation of fraudulent peptide bonds. We have prepared the following retro-inverso peptides, Tyr-Ile-Gly-Ser-gArg-CHO (1), Tyr-gIle-mGly-Ser-Arg-NH₂ (2), Tyr-glle-mGly-Ser-gArg-CHO (3), gTyr-D-rIle-mGly-Ser-Arg-NH₂ (4), Tyr-Ile-Gly-gSer-o-rArg-CHO (5) and Tyr-glle-rGly-D-rSer-D-rArg-CHO (6). In vitro assays for B16F10 melanoma cell adhesion showed no significant activity for these six peptides. Peptides 1-3, 5 and 6 were further tested, in vivo, for their ability to inhibit tumor metastases to the lung in mice injected in the tail vein with B16F10 melanoma cells. All five of the retro-inverso peptides tested showed statistically significant inhibition of metastasis, but the most active peptides were 5 and 6, which showed 57 and 69% inhibition of metastasis, respectively. © Munksgaard 1997.     

HPLC法测定八维钙锌片中维生素D_2和维生素E的含量

目的:建立RP-HPLC法测定八维钙锌片中维生素D2和维生素E含量的方法。方法:采用Phenomenex-C18柱(4.6 mm×150 mm,5μm);以为甲醇流动相;紫外检测波长为265 nm;流速为1 mL.min-1。结果:维生素D2的线性范围为0.8473～4.2365μg.mL-1(r=0.9996),平均回收率为99.7%,RSD%为1.82%(n=9);维生素E的线性范围为0.1625～0.8125mg.mL-1(r=0.9996),平均回收率为100.3%,RSD%为1.93%(n=9)。结论:本方法操作简便,结果准确、可靠,可同时测定八维钙锌片中维生素D2和维生素E的含量。     

Non-destructive determination of TiO2 concentration in cream formulation using Raman spectroscopy

The concentration of TiO₂ in a cream formulation has been non-destructively measured using Raman spectroscopy without further sample pretreatments. The distribution of TiO₂ particles in a highly viscous cream may not be homogeneous on a microscopic scale and local aggregation of the particles is possible; therefore, acquisition of Raman spectra capable of representing the whole sample identity rather than the localized chemical information was critically necessary to ensure reliable quantitative analysis. A wide area illumination (WAI) scheme, applying 6-mm diameter laser illumination area (total coverage: 28.3 mm²) on a sample, was used to achieve representative sample presentation and improved accuracy. When Raman spectra were collected for the same sample using a conventional scheme with a much smaller laser spot (∼100 μm), the spectral reproducibility was degraded, as expected. The local aggregation of TiO₂ particles was confirmed by analyzing both SEM (scanning electron microscopy) and Raman images of a cream sample. When the WAI scheme was used, the resulting error in the determination of TiO₂ concentration was 0.03 wt%, while 0.17 wt% in the case of using the conventional scheme. The proposed Raman scheme would be advantageous over the conventional titration method that requires destructive incineration of the organic cream matrix, as well as a large consumption of chemical reagents.     

复方缬沙坦双层片的处方筛选及优化

目的:优选由硝苯地平缓释层与缬沙坦速释层组成的双层片处方。方法:先制备硝苯地平固体分散体,以丙烯酸树脂Eudragit NE30D为缓释骨架材料,采用正交试验设计优选处方;然后以缬沙坦在30 min的释放度为评价指标优化速释层的处方。结果:硝苯地平缓释层的最佳处方为Eudragit NE30D(以聚合物干重计)3.0%,乳糖为40%,磷酸氢钙为35%;缬沙坦速释层的最佳处方为乳糖18%、微晶纤维素40%、羧甲基淀粉钠6%、十二烷基硫酸钠10%。结论:正交试验优化的双层片处方良好,达到了设计要求。     

Rapid determination of nitazoxanide in tablets using reversed-phase ultra-performance liquid chromatography (UPLC) and high-performance liquid chromatography

A simple and rapid determination method for nitazoxanide (NTZ), an antiprotozoal agent, was developed using reverse-phase HPLC and Ultra Performance Liquid Chromatography (UPLC). Only six minutes gradient condition for NTZ analysis using UPLC was achieved. The mobile phase consisted of a mixture of phosphate buffer (pH 6.0) and acetonitrile. The repeatability (relative standard deviation (RSD), n = 6) and the correlation coefficient from linearity (the range from 80% to 120% of amount) were 0.25% and 0.9963 for UPLC and 0.15% and 0.9988 for HPLC, respectively. The quantitative values of NTZ in tablets were 103.2% for HPLC and 98.7% for UPLC. The RSDs of quantitative values of sample solution were calculated to be 4.06% to 4.64% for HPLC and 0.15% to 0.36% for UPLC.     

Cloning,pharmacological characterization,and polymorphism screening of the guinea pig beta(2)-adrenoceptor

Beside its physiological function as a powerful host defense, neutrophil elastase is also known as one of the most destructive enzymes in the body. Current notion holds that neutrophil elastase is able to escape from regulation by multiple protease inhibitors at inflammatory sites. Once unregulated, this enzyme disturbs the function of the lung permeability barrier and induces the release of pro-inflammatory cytokines. These actions then cause symptoms that are typical in the pathophysiology of acute lung injury. In this article, we review recent progress in the understanding of the physiological activity of neutrophil elastase and its role in acute lung injury. Evidence in this review that supports the involvement of neutrophil elastase in the pathophysiology of acute lung injury includes: (1) neutrophil elastase levels are increased in both clinical and animal models of acute lung injury; (2) topical or systemic administration of neutrophil elastase produces typical symptoms of acute lung injury both in vitro and in vivo; and (3) inhibition of increased neutrophil elastase activity reduces symptoms of acute lung injury in animal models. A greater understanding of the role of this enzyme in the pathophysiology of acute lung injury will lead to better treatments for this complicated disease.     

FT-IR and Raman spectroscopic methods for identification and quantitation of orthorhombic and monoclinic paracetamol in powder mixes

FT-IR and Raman spectroscopic methods are suggested for identification of orthorhombic (form II) and monoclinic (form I) paracetamol and for their quantitative determination in mixes. The intensity ratio of the 836 cm(-1) FT-IR band (attributed to the presence of both forms) to the 806 cm(-1) monoclinic band plotted against the inverse monoclinic molar fraction (X) yields a straight line: I(836)/I(806)=0.515/X+0.700, r=0.9965 for eight calibration points on the regression line. Similarly, the area under the 454 cm(-1) band in FT-Raman spectra (which is attributed to both forms) over the area under the 465 cm(-1) band of monoclinic form is inversely related to its molar fraction (X): A(454)/A(465)=0.482/X-0.324, r=0.9954 for eight calibration points. Precision (RSD%) was <5% for both methods. Linear regression analysis between content and intensity of characteristic XRD reflections for four different samples gave r=0.9964 at 4.62 A and r=0.9894 at 3.70 A, for form II. For the content of form I, r=0.9596 at 3.37 A. The limit of detection for monoclinic form was estimated to be 0.012 mole fraction for both methods.     

环氧化酶-2抑制剂体外筛选模型在药物抗炎机制研究中的应用

目的考察化合物ZA-76和中药单体LM、XR和HQ对环氧化酶-2(COX-2)的影响。方法利用作者建立的COX-2抑制剂体外筛选模型。结果发现化合物ZA-76对COX-2有较强抑制作用，中药单体LM、XR对COX-2有一定的抑制作用，HQ对COX-2有较弱抑制作用。结论可以应用模型进行COX-2抑制剂的筛选，并能阐明部分抗炎药物的作用机制。