30results about How to "High derivatization efficiency" patented technology

The invention relates to an flatoxin and sulfanilamide drug light derivatization device. An array ultraviolet LED is taken as an excitation light source, and an excitation wavelength is between 280 nmand 380 nm. A fine internal-diameter pipeline which allows ultraviolet light to pass is taken as a derivatization reaction tank, the derivatization reaction tubes are arranged in a linear mode, the internal diameter of the derivatization reaction tube is 0.15-0.5 millimeters, a length is 0.5-12 meters, and the volume of the derivatization reaction tank is 100-1000 [mu]L. The fluorescence intensity of flatoxin B1 is increased by 6.5 times by the light derivatization device, and the light derivatization device is suitable for requirements of derivatization after high performance liquid chromatography columns and flow injection analysis derivatization.

The invention discloses a chemical derivatization method and an application thereof to nucleic acid modification detection by a liquid chromatogram-mass spectrometer (LC-MS) method. A derivatization strategy is performed on 5-methylcystein, 5-hydroxymethylcytosine, 5-aldehyde cytosine and 5-carboxylcytosine in deoxyribonucleic acid (DNA) by means of 2-bromo-1-(4-dimethylamino-phenyl)-ethyl ketone (BDAPE). Retention behaviors of modified nucleosides in reversed phase liquid chromatography are remarkably improved, and meanwhile, the detection sensitivity of the modified nucleosides in mass spectra is greatly improved. The chemical derivatization method has the advantages that the sensitivity and the selectivity are high, the operation is simple and convenient, quantitative detection of cytosine modification with extremely low abundance in the DNA can be achieved without complicated sample pretreatment, and the method can be applied to analysis of diseases and study on mutual relation among the 5-methylcystein, the 5-hydroxymethylcytosine, the 5-aldehyde cytosine and the 5-carboxylcytosine.

The invention relates to a method for detecting the content of an etimicin sulfate raw material and preparation of the etimicin sulfate raw material and relevant substances. The method adopts precolumn derivatization, the derivatization condition comprises taking 4ml sample with appropriate concentration, adding 1ml O phthalic aldehyde (OPA) solution into the sample, diluting the mixed solution with isopropyl alcohol to 10ml, heating the mixed solution at 30-60 DEG C in water bath away from light, and obtaining derivatization solution. The novel method for detecting etimicin sulfate adopts a high efficiency liquid chromatograph, the chromatographic condition is that an octadecylsilane chemically bonded silica filler chromatographic column has particle size ranging from 4-10mum, column specification is 150-250mmX4.6-8.0mm; flowing phase is divided into organic phase and aqueous phase, wherein the volume rate of the organic phase to the aqueous phase is 55-75:45-25, the organic phase is methyl alcohol or acetonitrile, the aqueous phase is glacial acetic acid containing 0.01M-0.03M ion pair reagent sodium heptanesulfonate, potential of hydrogen (PH) range is adjusted by ammonia water or ammonium acetate; flow speed is 0.5-1.0ml / min; sample feeding amount is 10-20mul; a detector is a conventional ultraviolet-visible light detector, and detection wavelength is from 330-350nm. The novel method for detecting etimicin sulfate adopts the conventional detector and the high efficiency liquid chromatograph, can achieve on-line detection of the content of the etimicin sulfate, the preparation of the etimicin sulfate and the relevant substances, and is simple, convenient, feasible, accurate and reliable.