METHOD FOR DETECTING NOTOGINSENG USING TERAHERTZ TECHNOLOGY

• US 20190323956A1
• Filed: 04/18/2019
• Published: 10/24/2019
• Est. Priority Date: 04/18/2018
• Status: Active Grant

• Current Assignee: University of Shanghai For Science and Technology
• Original Assignee: University of Shanghai For Science and Technology
• Inventors: PENG, Yan, ZHU, Yiming, KOU, Tianyi, SUN, Zhaozhao, XIAO, Haicheng, SHI, Chenjun, WANG, Liping, ZHUANG, Songlin
• Granted Patent: US 10,837,900 B2
• Time in Patent Office: Days
• CPC Class Codes: G01N 2021/3572 Preparation of samples, e.g. salt matrices
• CPC Class Codes: G01N 21/3563 for analysing solids; Preparation of samples therefor
• CPC Class Codes: G01N 21/3586 by Terahertz time domain spectroscopy [THz-TDS]

Abstract

A method for detecting notoginseng using terahertz technology. The notoginseng samples are pulverized in pulverizer. The pulverized samples are mixed with polyethylene powder in the ratio of 1:4 to 1:6. The powder mixture is pressed in a tablet press to obtain notoginseng tablet. Terahertz spectrograph is started. A peak is saved, and a background signal is measured. The time-domain graph of the background without sample is acquired. The time-domain graphs of the notoginseng tablets are acquired. The time-domain graphs are transformed into frequency-domain graphs by Fourier transform. The frequency-domain graphs are converted to obtain absorption spectrum of the notoginseng tablets. The absorption peak position of test tablet is compared with that of standard tablet to determine its authenticity. The concentration of key active substances of the notoginseng test sample is quantitatively analyzed by integrating the area under absorption peak curve of the notoginseng test sample.

Claims

1. A method for detecting notoginseng using terahertz technology, comprising:

1) pulverizing a notoginseng standard sample and a notoginseng test sample separately in a pulverizer;

then mixing the pulverized standard sample and the pulverized test sample respectively with a polyethylene powder with the same ratio of between 1;

4 and 1;

6 to obtain a standard powder mixture and a test powder mixture;

2) pressing the standard powder mixture and the test powder mixture separately in a tablet press to obtain a standard tablet and a test tablet for detection;

3) reducing the humidity in the sample chamber of a terahertz spectrograph to less than 3%;

storing a peak position;

measuring a single channel of background; and

acquiring a time-domain graph of the background without sample;

4) placing the standard tablet and the test tablet on a sample holder successively;

acquiring a time-domain graph of the standard tablet and a time-domain graph of the test tablet, respectively;

5) transforming the time-domain graphs of the background, the standard tablet and the test tablet into frequency-domain graphs by Fourier transform;

6) converting the frequency-domain graphs of the standard tablet, the test tablet and the background to obtain absorption spectra of the standard tablet and the test tablet by the following equation;

2. The method of claim 1, wherein in step 7), whether the position errors of absorption peak are within the resolution range of the terahertz spectrograph is further determined.