RESUMEN
Objective To analyze and compare the Eucommia ulmoides leaves from different producing areas by IR;To establish a TLC method for identification of Eucommia ulmoides leaves;To provide a reference for its quality control. Methods The characteristic absorption peaks were identified and the positions and intensities of Eucommia ulmoides leaves from 6 producing areas were compared by IR and second derivative spectrum, including clustering analysis; Separation and identification of the active components in Eucommia ulmoides leaves were conducted by TLC. Results There a difference exited in the characteristic absorption peaks in peakshapes, positions and intensities. And the samples from 6 producing areas could be divided into one category. Results found 6 batches of sample spots of consistent by TLC, but between samples of different producing areas trace components spots existed differences. Conclusion The two methods are direct, simple, fast and convenient, which can provide a reliable evidence for identification and quality control of the Eucommia ulmoides leaves.
RESUMEN
A new method of determination of COHb is reported in this paper by two- wavelength second-derivative spectrophotometry.Blood was diluted with a solution of THAM containing Na_2S_2O_4.The second-derivative spectrum was measured in the region of 500-600 nm and the derivative absorbance differerce ?Ax was deter mined at the wavelengths of 564 nm and 576 nm.Then the solution was satura- ted with CO gas.The second-derivative spectrum of COHb was measured in the same region.The derivative absorbance difference ?A_(100) was determined at the same wavelengths.The COHb in blood was calculated by the ratio of ?Ax to ?A_(100).The results of determination of COHb in standard blood samples were in good agreement with the theoretical values.