37 results about "Post column derivatization" patented technology

The invention discloses a method for detecting a complete degradation product of low molecular weight heparin based on post-column derivatization. The method comprises the following steps: degrading low molecular weight heparin to obtain a complete enzymatic product, separating the product by virtue of ion pair reversion phase chromatography, further carrying out post-column fluorescence derivation reaction, subsequently carrying out fluorescence detection, and analyzing to obtain the complete degradation product. In such a mode, the method of ion pair reversion phase chromatography with the combination of post-column fluorescence derivation is adopted, both detectable fluorescent groups are provided for low molecular weight heparin without ultraviolet absorption, and fluorescence detection with high sensitivity is achieved, and great practical values are achieved for development, production control and medicine security guarantee in low molecular weight heparin medicines.

The invention provides a pre-column electrochemical derivatization one-time total quantity measuring method for malachite green and leucomalachite green in aquatic products and belongs to one-time total quantity measuring methods for converting leucomalachite green into malachite green. The key of the method is that it is found that after a leucomalachite green solution is subjected to oxidation voltage +650 mv of an electrochemical Coulomb detector (ECD), averagely 98.86% of leucomalachite green is converted into malachite green, original malachite green is unchanged, and the total concentration of leucomalachite green and malachite green can be measured through a high performance liquid chromatograph in the one-time measurement process of leucomalachite green and malachite green in a sample. Sample pre-treatment time is greatly shortened, use of reagent consumables is reduced, and electrochemical precolumn derivatization is used for replacing post-column derivatization of lead dioxide in the national standard. The method has the advantages of being simple in sample pre-treatment, good in purification effect, high in derivatization rate and high in recovery rate.

The invention relates to a method for determining contents of cystine, cysteine and salt thereof in amino acid injection. The method comprises the following steps: measuring a sample to be detected and a reference solution precisely, adding 0.1-1% of sodium pyrosulfite solution, shaking up, heating by 70-100 DEG C. for 10-60 minutes, fetching out, adding formic acid 1.5 ml and 30% superoxol 1.0 ml, shaking up, placing in 30+-2 DEG C. for 30 minutes, adding water to the scale, shaking up, fetching the sample to be tested and injecting into a chromatograph with cation exchange resin, carrying out gradient elution and regeneration balance by a special-purpose mobile phase A6 solution and a special-purpose sodium hydroxide regeneration liquid, carrying out a post-column derivatization reaction by a special-purpose derivatization reagent ninhydrin solution, recording a chromatogram with the detection wavelength 570 nm, and obtaining the contents by calculating peak areas according to external standard method. The invention has the beneficial effects that (1) short analysis time and saved detection time; (2) high sensitivity; (3) low price and saved detection cost; (4) good specialization.

The invention discloses a liquid chromatography pre-column derivatization method for detecting glyphosate in water. The method comprises the steps as follows: S1, production of a standard curve; S2, preparation of a standard working solution; S3, preparation of a sample; S4, glyphosate derivatization; S5, online testing; S6, result determination; S7, quantitative measurement; S8, result calculation. With the adoption of the method, the glyphosate in water can be effectively detected and measured in the absence of a post-column derivatization instrument, a special detection chromatographic column and a post-column derivatization reagent, so that the laboratory cost is greatly saved, and the working efficiency is improved.