[Studies of Male Fertility with Raman Spectroscopy].

Raman spectroscopy which belongs to scattering spectroscopy obtained molecular vibrational and rotational information to achieve detection and analysis of molecular structure and corresponding changes through recording the frequency shift when light interacted with materials. Compared with routine biochemical analysis, Raman spectroscopy has the advantage of non-invasive, label-free and no sample requirement. Raman spectroscopy has been widely applied in biomedical field such as human tissue, organs, cells and human body fluids for disease diagnosis. This article mainly focuses on recent research advances of Raman spectroscopy in human semen. Firstly, Raman spectroscopy(including surface-enhanced Raman spectroscopy, SERS) employed in forensic science for semen analysis, and some related data processing methods were introduced, then Raman spectroscopy involved investigations of male fertility was highlighted, more specifically, the Raman-based qualitative and quantitative analysis which assist the objective detection and evaluation of male fertility. Furthermore, studies of single sperm cell based on micro-Raman system to characterize and evaluate sperm quality and the preliminarily obtained Raman biomarkers which indicate high-quality sperm cell were introduced. Finally, the potential development of Raman spectroscopy involved in reproduction and fertility field was also discussed.

[Advances in Raman Spectroscopy for Nasopharyngeal Carcinoma Tissue].

Nasopharyngeal carcinoma is a unique malignant tumor that has a distinct geographic and racial distribution, with a high incidence in southeast Asia and southern China. High degree of malignancy, poor prognosis and difficulty in early diagnosis remain a problem in nasopharyngeal carcinoma. Raman spectroscopy technique based on inelastic scattering is a rapid and nonivasive detection method, which is capable of providing the information of biochemical components at molecular vibration level.This article reviewed the recent research progress of nasopharyngeal carcinoma based on Raman spectroscopy. It mainly introduces the study of detecting nasopharyngeal carcinoma tissue by using Raman spectroscopy as well as surface-enhanced Raman scattering spectroscopy (SERS). The emphasis is put on the latest works by our research group, including high wavenumber Raman spectroscopy of tissue, Raman spectroscopy of tissue smears, and a specially designed endoscopic device combined with Raman spectroscopy for in vivo nasopharyngeal cancerous tissue detection, which was firstly developed by our group. Finally, the prospects of the development of Raman spectroscopy for nasopharyngeal carcinoma were discussed.

[Raman spectral analysis of theanine].

The L-theanine was tested using confocal Raman microscopy. Obvious Raman bands were showed in the range of 250 -1 700 and 2 800-3 000 cm(-1). The Raman bands were assigned with a preliminary analysis and the characteristic vibrational modes were gained in different range of wave numbers. Eight strong Raman bands were observed in the Raman spectra at 321, 900, 938, 1 153, 1 312, 1 358, 1 454 and 1 647 cm(-1), respectively. They are the characteristic Raman bands of L-theanine. The results showed that Raman spectroscopy might be a new kind of precise, direct and fast detecting method for theanine.

[Surface-enhanced raman spectroscopic analysis of largehead Atractylodes rhizome decoction].

The normal Raman spectra and surface-enhanced Raman spectra (SERS) of largehead atractylodes rhizome decoction were tested and analyzed. The characteristic Raman bands of largehead atractylodes rhizome decoction were tentatively assigned. Six obvious Raman bands (396, 548, 617, 730, 955 and 1327 cm(-1)) were observed in the SERS of largehead atractylodes rhizome decoction. The absorption spectra of largehead atractylodes rhizome decoction and the mixture of silver colloids and largehead atractylodes rhizome decoction were tested. A new resonance absorption peak (999 nm) appeared in the long-wavelength region in UV-Vis absorption spectra of the mixture. The adsorption characteristics and possible enhancing mechanism of the largehead atractylodes rhizome decoction on silver colloid were speculated. The results showed that the surface-enhanced Raman spectroscopy might provide a new kind of precise, direct and fast detecting method for the largehead atractylodes rhizome decoction or other traditional Chinese medicine.

[Infrared spectrum analysis of admixture decoction of herba Ephedrae with Ramulus cinnarnomi].

The infrared spectra of decoction of herba ephedra and ramulus cinnarnomi and the mixed decoction of herba ephedra + ramulus cinnarnomi were tested. The change in the mixed decoction was discussed to study the relationship between herba ephedra and ramulus cinnarnomi after decoction. The results showed that some components of herba ephedra and ramulus cinnarnomi were retained in the mixed decoction of herba ephedra + ramulus cinnarnomi, such as 1 205 and 1 074 cm(-1), but some components that never appeared in the two component spectra increased, such as 1 394 and 678 cm(-1). New absorption peaks were generated in the mixed decoction of herba ephedra + ramulus cinnarnomi, such as 757 and 407 cm(-1). It can be showed that there are differences in the chemistry environment of the various chemical groups in the three decoctions introduced above, and with the variation in absorption peak position, possibly some new chemical compositions were created. Medical ingredients in the decoction are not simply the addition of herba ephedra and ramulus cinnarnomi based on the studies of infrared spectrum of the mixed decoction of herba ephedra + ramulus cinnarnomi, and the new notion of prescription spectroscopy was proposed.

Gold nanoparticle based surface-enhanced Raman scattering spectroscopy of cancerous and normal nasopharyngeal tissues under near-infrared laser excitation.

The capabilities of using gold nanoparticle based near-infrared surface-enhanced Raman scattering (SERS) to obtain biochemical information with high spatial resolution from human nasopharyngeal tissue were presented in this paper. The gold nanoparticles used have a mean diameter of 43 nm with a standard deviation of 6 nm. The SERS bands of nasopharyngeal tissue were assigned to known molecular vibrations of nucleic acids, amino acids, proteins, and metabolites. We also observed the blinking phenomenon at the tissue level when measuring the nasopharyngeal tissue SERS spectra, most frequently in signal intensity but also occasionally in peak positions. This phenomenon is excitation light intensity dependent. This work demonstrated great potential for using SERS imaging for distinguishing cancerous and normal nasopharyngeal tissues on frozen sections without using any dye labeling or other chemical species as functionalized binding sites.

[Measurement of nasopharyngeal carcinoma tissue ex vivo by Raman spectroscopy].

Raman spectroscopy has shown its potential and advantages in detecting molecular changes associated with tissue pathology, which makes it possible to diagnose with optical methods non-invasively and real-time. A compact and rapid near-infrared (NIR)Raman system was developed using 785 nm diode laser, volume phase technology (VPT)holographic grating system and NIR intensified charge-coupled device (CCD)with a specially designed Raman fibre probe which can effectively reduce the interference of fluorescence and Rayleigh scattering, maximize the ability of Raman collection as well as correct the image aberration of a planar grating diffraction. Adopting this method, signal-to-noise ratio has been greatly improved and human tissue signals can be acquired in a short time. Raman signals from fat and musculature of fresh pork were measured and referenced for further optimization, then Raman spectra of nasopharyngeal carcinoma in vitro and the effect of storage time on them were measured in 1-5 s and discussed. The sensitivities and performance of the system will be further enhanced and more Raman data will be acquired and compared between normal and cancerous nasopharyngeal tissue, expecting to discover the statistical characteristics, which will benefit the diagnosis and treatment of early nasopharyngeal carcinoma or other tumors.

[Near infrared Raman spectra analysis of rhizoma dioscoreae].

A novel and compact near-infrared (NIR) Raman system was developed using 785 nm diode laser, volume-phase technology holographic system, and NIR intensified charge-coupled device (CCD). The Raman spectra and first derivative spectra of rhizoma dioscoreae were obtained. The Raman spectra of rhizoma dioscoreae showed three strong characteristic peaks at 477, 863 and 936 cm(-1), respectively. The major ingredients are protein, amino acid, starch, polysaccharides and so on, matching the known basic biochemical composition of rhizoma dioscoreae. In the first derivative spectra of rhizoma dioscoreae, the distinguishing characteristic peaks appeared at 467, 484, 870 and 943 cm(-1). Contrasted with rhizoma dioscoreae Raman spectra in the ranges of 600 to 800 cm(-1) and 1 000 to 1 400 cm(-1), the changes in rhizoma dioscoreae Raman first derivative spectra are represented more clearly than the rhizoma dioscoreae Raman spectra. So the rhizoma dioscoreae Raman first derivative spectra can be an accurate supplementary analysis method to the rhizoma dioscoreae Raman spectra.

[Two-photon excitation fluorescence of 5-ALA induced PpIX in DHL cells].

Two-photon fluorescence microscopy is a novel imaging technique, which is primarily sensitive to a specimen's response coming from an in-focus plane, thus has low photo-bleaching and photo-damage to biological samples. 5-ALA induced production of PpIX in DHL cells was excited by 820 nm femtosecond laser; two-photon excitation fluorescence of single cell was obtained in Lambda mode of laser scanning confocal microscope. The specific fluorescence intensity of PpIX which accumulated in DHL cells was measured at 2, 4 and 10 mmol x L(-1) concentration of 5-ALA with different incubation time, which reflected the kinetics of 5-ALA accumulated in DHL cells. Accumulation of PpIX in DHL cells was a dynamic change process. Biphasic alterations of PpIX accumulation were noted: PpIX content enhanced with the increasing time and reached the maximal value around 3 h, however PpIX content decreased in the subsequent incubation time. Results indicate that two-photon fluorescence based on laser scanning microscope can be a useful technology for studying the kinetics of 5-ALA induced PpIX production in DHL cells and other leukemia cells.

[Infrared spectrum analysis of admixture decoction of herba ephedrae with semen armeniacae amarum].

The infrared spectra of decoction of herba ephedra and semen armeniacae amarum and the mixed decoction of herba ephedra + semen armeniacae amarum were tested. The change in the the mixed decoction was discussed to study the relationship between herba ephedra and semen armeniacae amarum after decoction. The results showed that some absorption peaks of herba ephedra and semen armeniacae amarum were retained in the mixed decoction of herba ephedra + semen armeniacae amarum, such as 1402 and 1076 cm(-1), but some absorption peaks that never appear in the two ingredient spectra increased such as 1394 and 682 cm(-1). New absorption peaks were generated in the mixed decoction of herba ephedra + semen armeniacae amarum, such as 688 and 1187 cm(-1). It can be showed that there were differences in the chemistry environment of the various chemical groups in the three decoctions introduced above, with the variation in absorption peak position, and the biochemical structure of the material changed, possibly with some new chemical compositions created. Medical ingredients in the mixed decoction of herba ephedra + semen armeniacae amarum were not simply the addition of herba ephedra and semen armeniacae amarum based on studies of infrared spectrum of decoction, and the new notion of prescription spectroscopy was proposed.

[Spectral properties of the hemoporphyrin derivative interacting with hemoglobin].

The quenching reaction of hemoporphyrin derivative with hemoglobin (Hb) was studied by using fluorescence spectra and absorption spectra. It was shown that HpD has a powerful ability to quench the Hb fluorescence via a nonradiative energy transfer mechanism. The formation constants of them were analyzed at different temperature according to Stern-Volmer equation and double-reciprocal equation, which are bigger at high temperature than at low temperature. The critical binding site was calculated (R0 = 3.22 nm) by Föster energy transfer mechanism, and the thermodynamic parameters were obtained.

[Fourier transform infrared and near-infrared Raman spectra of human red blood cell].

The human red blood cell was studied by Fourier transform infrared and near-infrared Raman spectroscopy.The assignment of the characteristic groups of human red blood cell structure was basically confirmed. At the same time, the authors observed that the intensity of different Raman shift signal has different varying law when the power of laser is changing. Near-infrared laser Raman spectroscopy combined with infrared spectroscopy is an effective method to study the structure of human red blood cell.