Quantitative analysis by thin-layer scanning method mostly uses reflection method. The behavior of diffuse reflection light is complicated, and the optical path of instrument is complicated. Quantitative analysis of reflection absorbance is only applicable to low concentration range, and the linear range is narrow. Data is collected at single wavelength or dual wavelength. The amount of data is small and the precision is low, while the multi-wavelength scanning instrument is more expensive. Accordingly, an urgent need to increase the optical resolution of TLC scanner, adjust the optical path to reduce the influence of stray light, reducing equipment cost TLC scanner apparatus and methods for quantitative analysis studies.

The research mainly includes the following four aspects:

(1) A test system for constructing a thin layer in-situ reflection spectrum is to scan the spots in a "bow" shape two-dimensional movement mode, and set the interval recording time to record the photometric response values ​​at a plurality of wavelengths corresponding to the spots. Taking phenacetin and coffee as the analysis object, the results showed that the spotting amount of phenacetin was in the range of 2.00-24.00μg, and the linear correlation coefficient r between the reflection absorbance and the KM function value and the spot spotting amount was 0.9805 and 0.9990, respectively. The spotting amount range was reduced to 2.00-10.00μg and 8.00-24.00μg, and the linear relationship was above 0.9933. Compared with the reflected absorbance, the KM value was linearly correlated with the spot spotting amount.

The effect of velocity scanning on quantitative analysis was investigated. The K/S value on the caffeine spot area decreased with the increase of scanning speed. The scanning speed was in the range of 0.962-3.282mm/s. The linear relationship between KM value and speckle content was not significant. .

(2) Taking chlorogenic acid as the analysis object, the accuracy of thin layer in-situ reflectance spectroscopy analysis was investigated. TLC quantitative relationship identified sources of error in the position of the spot light collecting point corresponding to the intensity of the response analysis; 230.49-374.00nm in the wavelength range, the linear spot area value KM chlorogenic acid content correlation coefficient r = 0.9995; TLC chromatography scanner honeysuckle extract background, sample recovery experiment, recovery was 100.67%, the relative standard deviation (RSD) of 1.61% (n = 7), show that the method has good precision and accuracy, can be Meet the needs of quantitative analysis.

(3) A method for determining the content of chlorogenic acid in honeysuckle by multi-wavelength thin-layer in situ reflectance spectroscopy. The chlorogenic acid in the honeysuckle extract was separated on the polyamide film with a water content of 75% microemulsion and formic acid (6:1) as a developing agent. The experimental results show that there is a good linear relationship between the KM value and the chlorogenic acid content in the spot area. The content of chlorogenic acid in the honeysuckle is 4.983mg/g and the RSD is 2.35% (n=6). The recovery rate was 98.87%, the RSD was 2.90%, and the detection limit was 19 ng. The content of chlorogenic acid in honeysuckle was 5.158 mg/g as determined by high performance liquid chromatography. The results measured by this method are basically consistent with the results of high performance liquid chromatography.

(4) The analysis of the thin-layer chromatographic separation process of honeysuckle extract was carried out by thin-layer chromatography .

After thin layer separation, the honeysuckle extract showed 10 spots on the polyamide film, and the spectrum on the peak of the chromatogram was extracted and separated. The thin layer separation process was analyzed to provide a research basis for the optimization of the conditions of thin layer chromatography.

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