33 results about "High pressure liquid chromatography procedure" patented technology

In one aspect the invention is a composition comprising a prepolymer which is the reaction product of di(isocyanatophenyl)methane or a polymeric di(isocyanatophenyl)methane having an isocyanato functionality of about 2.1 to about 3.0 with a mixture of one or more diols and one or more triols wherein the ratio of isocyanate equivalents to hydroxyl equivalents in the reaction mixtures used to prepare the prepolymer is from about 1.2 to about 1.8 and the ratio of diol to triol where the diisocyanate is a di(isocyanatophenyl)methane in the reaction mixture is from about 5:1 to about 1:1. and where the isocyanate is a polymeric di(isocyanatophenyl)methane is from about 8:1 to about 4:1; wherein the prepolymer could further react with an isocyanate reactive monofunctional compound. The prepolymer herein has an isocyanate content of about 0.5 to about 1.5 percent by weight, a free isocyanate monomer content of about 1.0 percent by weight or less as measured by high pressure liquid chromatography. These prepolymers can be used in many applications including adhesive, sound dampening sealer and coating and especially in making adhesives or adhesive systems with a low content of monomeric isocyanate to bond together similar or dissimilar substrates such as metal, glass, ceramics, plastic and painted steel panel.

The invention belongs to the technical field of natural product extraction from oranges, and specifically relates to a method for continuously extracting natural activated products such as synephrine, hesperidin and limonin from physiological orange drops. The method comprises the following steps: using orange drops which are dried and crushed into 20-100 meshes as raw materials, adding 50-90% ethanol according to a weight/volume ratio of (1:10)-(1:50), extracting under reflux at 40-80 DEG C for 1-3 hours, filtering, recovering ethanol from the filtrate, and obtaining a concentrated solution for later use; adding a small number of chloroform crystals into the concentrated solution, adding water for layering, directly heating the water layer to 75 DEG C, filtering, adding 0.1mol/L hydrochloric acid to regulate the pH value to 3-4, and precipitating to obtain a hesperidin crude product; carrying out spin drying on the obtained chloroform layer solution, adding a right number of acetone crystals, and carrying out vacuum drying to obtain a synephrine crude product; and carrying out spin drying on the acetone solution after the crystal filtration, adding dichloromethane for dissolution, filtering, adding isopropanol into the solution according to a volume ratio of 1:2, and crystallizing to obtain a limonin crude product. Qualitative and quantitative analysis are carried out on the three resulting activated products through high-pressure liquid chromatography, and the result shows that the hesperidin has the highest purity (91.41%).

A polycarbonate resin that after alkaline hydrolysis with sodium hydroxide contain an amount of 0.01 to 150 ppm of carbamate compounds according to formula (1)

wherein

• • R¹ and R² independently of one another denote hydrogen or C₁-C₁₂-alkyl, or together denote C₄-C₁₂-alkylidene,
  • and R³ and R⁴ independently of one another denote hydrogen, C₁-C₁₂-alkyl or phenyl, or together with the carbon atom to which they are bonded form cyclohexyl or trimethylcyclohexyl, said amount measured after alkaline hydrolysis with sodium hydroxide by high pressure liquid chromatography.

The invention relates to a method for preparing momordica grosvenori squalene, which comprises the following step: breaking kernels or seeds of the momordica grosvenoris, leaching the liposolubility substance by organic solvent, then removing the organic solvent in the liposolubility substance to get the crude momordica grosvenori squalene, getting raw momordica grosvenori squalene through a silica gel chromatography column and eluting by organic solvent, collecting the achromatic color part of the eluent, removing the organic solvent using vacuum distillation process to get the momordica grosvenori squalene super quality. The content of squalene is more than 40 % in the crude production and more than 95 % in the exquisite production. The production has the special perfume and can substitute completely squalene abstracted from the liver of abyssal sea sharks.

The invention discloses aspergillus niger and a method for catalytically producing fructo-oligosaccharide by virtue of whole-cells of aspergillus niger. The aspergillus niger FOS-0620 is an aerobe, has black spores and milk-white hyphae, and is collected in China General Microbiological Culture Collection Centre (CGMCC for short) on September 28, 2012. The method for catalytically producing fructo-oligosaccharide by virtue of whole-cells of aspergillus niger comprises the following steps of: (1) preparing aspergillus niger whole-cells by virtue of the aspergillus niger FOS-0620 according to claim 1; and (2) catalytically producing fructo-oligosaccharide by virtue of the aspergillus niger whole-cells. The product obtained by the method disclosed by the invention is detected that the content (occupying total solids) of the fructo-oligosaccharide is not less than 50% via high-pressure liquid chromatography; and the method disclosed by the invention is simple in process, convenient to operate, high in enzymatic activity, high in conversion efficiency, and important in industrial value.

The invention relates to a high-pressure liquid chromatography of a diode array detector for detecting tripolycyanamide in foods, which is characterized by comprising the following steps of: sampling and then extracting tripolycyanamide by 0.2-0.3% trichloroacetic acid; precipitating protein in extracting liquid by a precipitating agent; centrifugally separating supernatant in the extracting liquid, purifying and filtering; setting the method of a liquid chromatography instrument of the diode array detector to recognize the tripolycyanamide and a hydrolysis product; preparing a standard curve to obtain a regression equation of an analyzing method; detecting the tripolycyanamide by a liquid chromatograph and calculating the tripolycyanamide content. The 0.2-0.3% trichloroacetic acid extracting liquid has good extracting effect and less detecting interference; the protein is precipitated by zinc acetate and potassium ferrocyanide, the precipitation efficiency is high, and the pollution is less; the tripolycyanamide and the hydrolysis product can be detected, the result is more accurate, the used instrument and reagent are cheap and are easy for popularization, and the liquid chromatography is suitable for the detection of a plurality of samples.

The invention discloses a method for preparing kestose and nystose through yacon. Method of water extraction by alcohol sedimentation is adopted and supernate thereof is taken, concentrated, frozen and dried to obtain faint yellow yacon oligosaccharide. The yacon oligosaccharide is analyzed through high pressure liquid chromatography with a chromatography condition as follows: a chromatographic column is APS-2HYPERSIL, a column temperature is 30 DEG C, a moving phase is acetonitrile-water (75 to 25, V/V), a flow velocity is 0.8ml/min, a sample size is 20 Mul and a differential detector is arranged. The yacon oligosaccharide comprises fructose, glucose, saccharose, kestose, nystose and 1F-Fructofuranosyl nystose with contents respectively as 38,30 percent, 16.44 percent, 14.58 percent, 12.29 percent, 12.17 percent and 6.2 percent. Silicagel column chromatography is implemented on a prepared oligosaccharide sample; glacial acetic acid, chloroform, absolute ethyl alcohol and water with a proportion of 3 to 11 to 11 to 1 are used as an eluant for elution; the eluant is collected in sequence and then is concentrated, frozen and dried to obtain the kestose and nystose. The purity of the kestose and nystose prepared through high pressure liquid chromatography can be more than 90 percent.

A cannabis based therapeutic product for treatment of chronic pain produced by separating hash resin from plant material of the cannabis plant, pressing the hash resin to expel oil, leaving spent hash resin, extracting further cannabinoids from the spent hash resin using MCT oil, separating the cannabis compounds from the oils using high pressure liquid chromatography, flash chromatography, or similar techniques, and processing selected cannabis compound formulations into a pill, tablet, liquid, or other form suitable for administration as a therapeutic product for treatment of chronic pain, optionally with the further step of enriching the product with a formulation comprising at least 1% by weight purified -myrcene, prior to processing into a final product.

An installation for separating components, in particular by high-pressure liquid chromatography along a plurality of channels in parallel, the outlets from the channels being connected via controlled selective connection means to the inlets of parallel temporary storage means whose outlets are connected via controlled selective connection means to ducts for depositing in collector means or in disposal means.

This invention relates is a label-free, enzyme-free, aptamer-free method for simultaneously measuring adenosine, and its intracellular metabolites, e.g., AMP, ADP and ATP, using high pressure liquid chromatography coupled to electrochemical detector (HPLC-ECD).

A cannabis-based therapeutic product for treatment of chronic pain produced by separating hash resin from plant material of the cannabis plant, pressing the hash resin to expel oil, leaving spent hash resin, extracting further cannabinoids from the spent hash resin using MCT oil, separating the cannabis compounds from the oils using high pressure liquid chromatography, flash chromatography, or similar techniques, and processing selected cannabis compound formulations into a form suitable for administration as a therapeutic product for treatment of chronic pain. The therapeutic product has at least 28% w/w cannabinol (CBD), and at least 2% w/w β-myrcene.

The present invention provides a process for purifying the cinnamoyl-C-glycoside, <DEL-S DATE="20020625" ID="DEL-S-00001"/>8-C-beta-D-[2-O-(E)-cinnamoyl]glycopyranosyl-2- [(R)-2-hydroxy]propyl-7-methoxy-5-methyl-chromone.<DEL-E ID="DEL-S-00001"/> <INS-S DATE="20020625" ID="INS-S-00001"/>8-C-beta-D-[2'-O- (E)-cinnamoyl]glycopyranosyl-2-[(S) -2-hydroxy]propyl-7-methoxy-5-methylchromone, <INS-E ID="INS-S-00001"/>referred to herein as the "540 compound." In one embodiment of the present invention the 540 compound is purified by extraction from a decolorizing agent with an organic solvent. The extracted product can be purified by high pressure liquid chromatography. In a second embodiment crude 540 compound, which has not been treated with a decolorizing agent, is purified by passage over neutral alumina or sephadex.

The present invention discloses a fingerprint detection method of white ginseng bacteria. The fingerprint is determined by using a high-pressure liquid chromatography with reference to a schizophyllanreference substance. According to the method provided by the present invention, the HPLC characteristic fingerprint of white ginseng bacteria is established, and the singularity and one-sidedness ofthe existing quality standards can be overcome; the quality information of white ginseng bacteria can be fully reflected, so that the purpose of more comprehensively and effectively controlling the white ginseng bacteria quality can be achieved; and the fingerprint of the white ginseng bacteria obtained by using the method provided by the present invention has many peaks, a good peak shape, easy identification, high similarity, and accuracy and reliability.