Drug analysis by Raman and micro-Raman spectroscopy

The technique of Raman spectroscopy, resonance Raman spectroscopy and micro-Raman spectroscopy is described for application to drug analysis and investigation. Possibilities and limits are mentioned for qualitative and quantitative analyses as well as for studies of structure and interactions. Some principal interaction modes, such as hydrogen bonding, proton transfer, charge transfer and ion-molecule attraction, are shown to explain drug reactivity. Illustrations are given based on several drug families, in particular vitamins, anti-depressants, cardio-active and anticancer drugs.     

拉曼光谱在药物分析中的应用

自1928年发现拉曼现象和随之建立拉曼光谱法以来,经过近八十年来科学工作者的不懈努力,拉曼光谱已经得到了很大的发展。特别是20世纪90年代之后,随着光纤样品探头、组合光学设计、计算机以及数据获取、处理、分析等技术的发展,解决了仪器的一些局限,从而使拉曼光谱仪的性能得到很大提高,使其更具有实际应用的价值。本文将着重介绍近年来傅立叶变换拉曼光谱和表面增强拉曼光谱技术在药物分析中的一些应用。     

应用拉曼光谱技术诊断动脉粥样硬化的展望

简要评述目前各种动脉粥样硬化诊断方法和技术发展现状以及未来有可能在临床上实现的技术和方法.分析和展望拉曼光谱作为一种具有应用潜力的新技术,在动脉粥样硬化诊断中的实现手段及应用前景.     

Probing tumor and peritumoral tissues in superficial and nodular basal cell carcinoma using polarized Raman microspectroscopy

Abstract:  Basal cell carcinoma (BCC) can sometimes lead, through a possible invasion of the dermis and the subcutaneous tissue, to serious local damage to the patient. Several histological types of BCC are reported, among them, the superficial, nodular and infiltrative forms. This study reports the use of polarized Raman microspectroscopy on the nodular and superficial types to discriminate between healthy epidermis and tumor, and between normal and peritumoral stroma. This technique probes additional information than conventional Raman spectroscopy because it is sensitive to the molecular ordering of tissue components. Depolarization ratios and hierarchical cluster analysis demonstrate that polarized Raman microspectroscopy can better identify the tumor and the peritumoral dermis than conventional Raman microspectroscopy, and hence gives potential complementary data about their molecular characteristics (molecular composition, secondary structure of proteins, intra- and/or inter-molecular bonding). Our findings also show that although superficial and nodular types of BCC were analysed, clear differences between the spectra of peritumoral and normal dermis could be detected.     

胶质瘤术中快速病理精准诊断的研究进展

胶质瘤是最常见的中枢神经系统恶性肿瘤，手术切除是临床治疗胶质瘤最成熟、治愈率最高的方法。在术中术者面临的主要难题是尽可能保留功能的前提下彻底切除病灶，而不断发展的术中快速病理诊断技术给予了术者极大帮助，可以使术者在术中对肿瘤的性质和类型、浸润程度、范围及手术切缘等做出快速、精确的判断，从而在第一时间为患者制定更科学、更准确的治疗方案。该文概述了目前各类术中快速病理诊断技术的主要特点，对胶质瘤术中快速病理精准诊断的研究进展做一综述。 [国际神经病学神经外科学杂志, 2023, 50(2): 71-76]     

Cell Death Discrimination with Raman Spectroscopy and Support Vector Machines

In the present study, Raman spectroscopy is employed to assess the potential toxicity of chemical substances. Having several advantages compared to other traditional methods, Raman spectroscopy is an ideal solution for investigating cells in their natural environment. In the present work, we combine the power of spectral resolution of Raman with one of the most widely used machine learning techniques. Support vector machines (SVMs) are used in the context of classification on a well established database. The database is constructed on three different classes: healthy cells, Triton X-100 (necrotic death), and etoposide (apoptotic death). SVM classifiers successfully assess the potential effect of the test toxins (Triton X-100, etoposide). The cells that are exposed to heat (45 °C) are tested using the classification rules obtained. It is shown that the heat effect results in apoptotic death, which is in agreement with existing literature.     

The elastin network: its relationship with collagen and cells in articular cartilage as visualized by multiphoton microscopy

A combination of two‐photon fluorescence (TPF), second harmonic generation (SHG) and coherent anti‐Stokes Raman scattering (CARS) imaging has been used to investigate the elastin fibre network in healthy equine articular cartilage from the metacarpophalangeal joint. The elastin fibres were identified using their intrinsic two‐photon fluorescence and immuno‐staining was used to confirm the identity of these fibres. SHG was used to reveal the collagen matrix and the collagen fibre orientations were determined from their SHG polarization sensitivity, while CARS was used to clearly delineate the cell boundaries. Extensive elastin fibre networks were found in all the joint regions investigated. The elastin was found predominantly in the superficial zone (upper 50 μm) and was aligned parallel to the articular surface. Elastin was also detected in the pericellular matrix surrounding the superficial chondrocytes; however, individual fibres could not be resolved in this region. Variations in the density and organization of the fibres were observed in different regions on the joint surface.     

Raman Spectroscopy Detects Cardiac Allograft Rejection with Molecular Specificity

Spatially resolved Raman spectroscopy is shown here to be capable of molecular‐specific detection without exogenous labeling. This molecular specificity is achieved by detecting the strong and characteristic Raman spectral signature of an indole derivative, serotonin, whose selective existence in rejected heart transplants serves as the biomarker. The study also corroborates the increasingly recognized role of serotonin receptors in various immune responses, including cardiac allograft rejection. Combining both medical and physical sciences, this work demonstrates the potential use of Raman spectroscopy in replacing the invasive endomyocardial biopsy as the standard for post‐transplantation rejection surveillance and presents a new paradigm in advancing clinical care through interdisciplinary studies.     

伢典去龋后牙本质表面的激光拉曼光谱分析

目的:评价伢典去龋后牙本质表面的化学性质.方法:选取无龋坏离体牙3颗和龋坏到牙本质的离体牙9颗,分为4组,正常组、龋坏组、伢典组、机械组,前两组不做处理,后两组分别伢典去龋和车针去龋.利用激光共聚焦显微拉曼光谱仪分别检测4组样本的牙本质表面的拉曼光谱信号.结果:正常组、伢典组、机械组牙本质均在430、581、960、1071、1650、1451、1245 、2940 cm-1处出现拉曼峰.龋坏组无法采集到特征信号.结论:伢典处理牙本质表面类似于于车针去龋牙本质表面和正常牙本质表面.