Biomedical subjects

Jun-ming Tang

Publications and source records attributed to Jun-ming Tang.

5 recordsLinked to original sources

PubMed2005

[Ion solvation and ion association in high-concentration of NaBF4/DMF solutions].

Ion solvation and ion association in solutions of NaBF4/DMF were studied by infrared and Raman spectroscopy and ab initio quantum chemistry. It was found that the sodium cation interacts on oxygen atom of C=O group in DMF molecules. The solvation number of Na+, four, was obtained according to the change analysis of CH3 rocking band. The splitting of the nu1 mode of BF4(-) anion indicates the presence of contact ion pairs. Ionic association degree increases with increasing molality of the salt. The solvated structure of Na+ and the geometry of Li+ BF4(-) ion pair were also suggested based on the ab initio calculations.

Algorithms↗

PubMed2004

[Study on the rapid and nondestructive identification of TCM formula particles by FTIR].

Formula particles made by Traditional Chinese Medicines (TCM) were studied systematically via Fourier Transform Infrared Spectroscopy (FTIR) in this paper. The products quality of different pharmaceutical factories (Guangdong Yifang, Jiangyin Tianjiang, Sanjiu Yiyao, Hongkong Purapharm) could be revealed directly in the FTIR spectra. Also the spectra of different batch numbers (same factory), particles before and after processing, and particles with different processing methods were studied. It is proved that FTIR is an effective, fast and advanced method to evaluate the production qualities.

Drugs, Chinese Herbal↗

PubMed2003

[The effect of crystallization of calcium carbonate on the secondary structure of pepsin].

The effect of crystallization of calcium carbonate on the secondary structure of pepsin was studied by Fourier transform infrared spectroscopy, derivative, deconvolution and curve-fitting techniques in this paper. The result shows that the pure protein is composed of 24.38% alpha-helices, 29.91% beta-sheets, 39.22% beta-turns and 6.49% random structures, and the pepsin in the CaCO3/pepsin solution is composed of 2.09% alpha-helices, 93.304% beta-sheets, 4.60% beta-turns and 0.006% random structures. From these data we can see that the alpha-helices decrease and the beta-turns increase with the formation of the crystal of calcium carbonate. The essence of these changes is discussed in the paper.

Calcium Carbonate↗

PubMed2003

[FTIR and classification study on trueborn tuber dioscoreae samples].

To identify the origin of tuber dioscoreae, 45 samples were studied by soft independent modeling of class analogy (SIMCA) in this paper. The combination of Fourier transform infrared spectroscopy (FTIR) with mathematic method was used to classify the trueborn and non-trueborn samples. The samples were chosen randomly as modeling group and predicting group. The correctness of classification was 70%. This approach was proved to be a reliable and practicable method for trueborn quality analysis of tuber dioscoreae.

Dioscorea↗

PubMed2003

[Study on the kinetic fluorimetric determination of tannins in tea].

A simple and highly sensitive kinetic fluorimetric method is proposed for the determination of trace tannins, based on the activation of tannins on the oxidation of pyronine Y by hydrogen peroxide catalyzed by Cu(II) ion. The effects of some experimental conditions were investigated and discussed in detail. The fixed reaction time procedure was used to determine the fluorescence intensity of the system. The calibration curve of tannin was linear in the range of 0.06-0.96 mg.L-1, and the detection limit for tannin was 0.032 mg.L-1. The relative standard deviation for the measurement of 0.32 mg.L-1 tannin (n = 11) was 2.3%. The proposed method has been successfully applied to the determination of tannins in tea. The results obtained were compared with those provided by the Folin-Ciocalteu method.

Calibration↗