Infrared Spectrum Combining With Chemometric Methods Is Applied To The Research Of Fern Hemp Of National Medicine

National medicine in China, which has two thousand years, is animportant part of traditional medicine, and it has a history of more thantwo thousand years. Because national medicine has unique efficacy, richresources of pharmaceutical, treatment of diseases and so on, its role，showing the irreplaceable unique role by other drugs，has became moreand more popular among people. Used a variety of chemometrics methods，This paper that establishes fern hemp’s quality evaluation methodtries to find out this medicine’s infrared spectroscopy feature andregularities of distribution through Infrared spectrum technologyresearch, so that we can use modern analytical technique and themethod of the information analysis to identify the Tibetan medicine.All these will provide much better scientific basis for Tibetan medicine.Infrared spectrum and the application of fern hemp’s work is notmore systematically studied in the literature. This paper selects twelvedifferent samples of fern hemp from different areas, then throughIRPrestge-21Fourier transformation infrared spectrometer, the twelveinfrared spectra of fern hemp samples are studied. Used a variety ofchemometrics techniques, the experimental data is analyzed to set upTibetan medicine quality evaluation method of the infrared spectrophotometry by MATLAB Engineering design software and SPSSsoftware，and the main content are as follows:1、Infrared spectrum of fern hemp in different places have moresystematically been obtained, then infrared spectrum of typical fern hempwere analyzed. As fern hemp of same species, the infrared spectrumcharacteristics and distribution regulation of different parts prove thatbecause the main chemical components are the same, the spectrum as a wholeand the quality of medicinal materials are mainly similar. Because thereare differences in producing area, climate, soil and other factors, itwill be different in chromatogram fingerprint of each sample.2、In data preprocessing of the standard normal transformation, themultiple scattering correction, the derivative correction and the wavelettransform, the Wavelet denoising effect is best.3、Signal noise reduction of wavelet analysis, the basic principleof compression and the evaluation index are set up. It determines theappropriate mother wavelet function and threshold. When they are denoised,the root mean square error of all samples, reaching10-4orders of magnitude,is very small. Its precision is the same as the spectral accuracy. Theoriginal data that was denoised is compressed. The1868figures arecompressed to241, for one-eighth of the original data. The root meansquare error of all samples of the compression is very small, up to10-5orders of magnitude, showing that the compression effect is very good. 4、 Used the principal component analysis, the two principalcomponents are determined, accounting for99.44%of the total amount ofinformation. Through revealing the infrared spectrum characteristics anddistribution regulation of different places, they achieve the correctclassification of the samples, thus the fern hemp quality evaluationmethod in medicine has been established. The clustering analysis, whichwas adopted, has verified the results.5、The quality evaluation indexes of fern hemp are identified bysimilarity, included Angle cosine and grey correlation analysis.correlation coefficients and Angle cosine, whose most are around0.99witha tiny part of0.98to0.97, are more concentrated, but grey correlationcoefficient data is more scattered, distributing0.9to0.6.6、The fern hemp pattern recognition of different regions isestablished through the PCA-ANN-BP method.7、These analysis results of the chemometrics pattern recognitionshow us that the infrared spectroscopy which combines with thechemometrics spectra analysis can be regarded as the analysis test methodfor the Tibetan medicine. Compared with the chromatographic process, thismethod can be much easier for us to use it widely because it can figureout the accurate result quickly with simple sample preparation.