36results about How to "Excellent chromatographic performance" patented technology

The present invention is a surface-modified base matrix comprised of a porous polymeric base matrix onto which branched hydrophilic polyhydroxy-functional polymers have been covalently attached, wherein the polyhydroxy-functional polymers are hyperbranched polymers presenting a degree of branching (DB) of at least about 0.2 and each polymer is tethered to the base matrix at two or more points. The present matrix can for example be a cross-linked carbohydrate material, such as agarose, and the hyperbranched hydrophilic polymer can e.g. be a copolymer of epichiorohydrin and a sugar. The invention also relates to a method of surface-modification of a porous base matrix by activating functional hydroxy groups thereon and contacting the activated matrix with a hydrophilic hyperbranched hydroxy-functional polymer.

The invention discloses a solid-phase dehydration extraction-supercritical fluid chromatography-mass spectrometry online analysis system, which includes an online enrichment-removal-cleaning device and an online dehydration-desorption-dilution-chromatographic separation device, and the device includes a carbon dioxide pump , three chromatographic pumps, two six-way switching valves, autosampler, extraction column, mixer, chromatographic column, three-way connector, mass spectrometer detector, through online enrichment-removal-cleaning device and online dehydration- The combination of desorption-dilution-chromatographic separation device realizes the online combination of supercritical fluid chromatography technology and pretreatment technology, enabling supercritical fluid chromatography technology to directly analyze aqueous samples. The entire analysis process is automatically controlled, with good chromatographic performance, high accuracy and precision, and can be effectively applied to the rapid analysis and detection of trace organic compounds in complex aqueous samples or aqueous extracts.

The invention discloses preparation and application of a zeolite imidazate framework material ionic liquid organic polymer fixed-phase capillary electrochromatography monolithic column, and belongs tothe field of analytical chemistry. By an in-situ polymerization method and an embedding method, the zeolite imidazate framework material ionic liquid organic polymer fixed-phase capillary electrochromatography monolithic column is synthesized by one step, zeolite imidazate framework materials are effectively fixed, an idea is provided for development of a novel capillary electrochromatography monolithic column, and chromatographic fixed-phase sources are greatly extended. The preparation method of the capillary electrochromatography monolithic column is simple, the fixed-phase material sources are wide, chromatographic performance is excellent, column efficiency is high, electroosmotic flow can be generated at the pH (potential of hydrogen) of 2.0-12.0, alkyl benzene series and phenol substances are rapidly and efficiently separated and detected, and the monolithic column has a great application potential in separation of complicated component substances.

The invention discloses a technique for extracting and purifying tea polyphenols by using spherical polyamide resin, in which tea leaves are extracted and filtered; the filtered tea extract solution is loaded into a chromatographic column equipped with spherical polyamide chromatographic resin Carry out chromatography; first use citric acid aqueous solution as the eluent to wash away caffeine and pigment, then use ultrapure water, and finally use ethanol aqueous solution as the mobile phase to elute tea polyphenols; finally wash the collected tea polyphenols Deliquoring and concentrating crystallization to obtain a colorless and transparent tea polyphenol crystallization product; the present invention uses a spherical polyamide resin to extract and purify tea polyphenols, the extraction method is simple, green and pollution-free, and the production cost is low, only one step is required Analysis and purification can meet the requirements of tea polyphenols purity greater than 99%, and extraction rate greater than 90%, and the prepared tea polyphenols have high yield, high extraction rate, and high quality, which can meet the requirements of more fields, so as to meet more Extensive market demand.

The invention discloses a pyridinedicarboxamide group bridged bis-β-cyclodextrin stationary phase and a preparation method and application thereof. 3-Isocyanatopropyltriethoxysilane and SBA-15 are prepared as raw materials, and the preparation method has simple process, mild conditions and low cost; The stationary phase is a kind of multi-mode stationary phase with a wide range of separation objects, which can efficiently and quickly resolve a series of acidic, basic, neutral and amphoteric chiral drugs or pesticides in liquid chromatography.

The invention discloses a method for preparing a high-efficiency liquid-phase chromatogram filler, in particular to a method for preparing a polyvinyl imidazole type silica gel filler by an atom transfer free radical polymerization technique. The method comprises the following steps of: bromizing full porous spherical silica gel modified by an aminopropyl silanization reagent to prepare bromized silica gel; and performing atom transfer free radical polymerization on the bromized silica gel and N-vinylimidazole to generate polyN-vinylimidazole grafted silica gel. The filler has the advantages of uniform thickness of a polymerized layer, controllability, multiple action mechanism, capacity of separating many kinds of substances under the same chromatographic mode, separation under inverse phase, normal phase and ion chromatography modes, high selectivity and stability, symmetrical peak shape, high column efficiency, large column capacity, good application potential and the like.

The invention discloses an optically pure mandelic acid derivative-cellulose chiral stationary phase, a preparation method and an application. Use optically pure mandelic acid or optically pure mandelic acid derivative acid halide and microcrystalline cellulose to prepare chiral chromatography column precursor, and coat or bond on the surface of chromatography-grade silica gel to form chiral column packing, which is further prepared Stainless steel chiral column can be used for the separation and analysis of various chiral substances.