Abstract

An amphoteric dissociation ion exchange separation medium, the surface of which is an amphoteric dissociation covalently-modified layer. When an environmental pH value is lower than the isoelectric point, pIm, of the covalently-modified layer, the type of net charges on the surface of the covalently-modified layer is positive and the separation medium has the properties of an anion exchanger; when the environmental pH value is higher than the pIm, the type of net charges on the covalently-modified layer surface is negative and the separation medium has the properties of a cation exchanger. The separation medium has the properties of an anion exchanger and a cation exchanger at both sides of the pIm, respectively. The pH of an eluent can be adjusted to allow the separation medium surface and the target substance to have the same type of net charges, so that the target substance can be released by electrostatic repulsion.

IPC Classes  ?

• B01J 43/00 - Amphoteric ion-exchange, i.e. using ion-exchangers having cationic and anionic groupsUse of material as amphoteric ion-exchangersTreatment of material for improving their amphoteric ion-exchange properties
• B01J 47/014 - Ion-exchange processes in generalApparatus therefor in which the adsorbent properties of the ion-exchanger are involved, e.g. recovery of proteins or other high-molecular compounds
• C07K 1/18 - Ion-exchange chromatography
• G01N 1/40 - Concentrating samples
• G01N 21/31 - Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
• G01N 21/80 - Indicating pH value
• C12N 15/10 - Processes for the isolation, preparation or purification of DNA or RNA
• C12Q 1/6806 - Preparing nucleic acids for analysis, e.g. for polymerase chain reaction [PCR] assay

Abstract

An amphoteric dissociation ion exchange medium. The surface of the amphoteric dissociation ion exchange medium is an amphoteric dissociation covalent modification layer. When an environmental pH value is lower than an isoelectric point of the amphoteric dissociation covalent modification layer, the surface net charge of the amphoteric dissociation covalent modification layer is positive, so that the amphoteric dissociation covalent modification layer has the property of anion exchanger; when the environmental pH value is higher than isoelectric point of the amphoteric dissociation covalent modification layer, the surface net charge of the amphoteric dissociation covalent modification layer is negative, so that the amphoteric dissociation covalent modification layer has the property of cation exchanger. The separation medium respectively has the property of the anion exchanger and the cation exchanger at the two sides of the isoelectric point, so that by adjusting the pH value of an eluant, the net charges on the surface of the separation medium and a target substance are same, so that a target substance can be released due to electrostatic repulsion, the elution effect is enhanced and subsequent problems due to application of high-concentration inorganic ions are avoided. The novel ion exchange medium has a high separation capacity, a high elution effect on the absorbed ions in a moderate condition, can accurately calibrate a separation capacity, has low non-specific adsorption to hydrophobic small molecules, and has a high regeneration effect in the moderate condition.

IPC Classes  ?

• B01J 43/00 - Amphoteric ion-exchange, i.e. using ion-exchangers having cationic and anionic groupsUse of material as amphoteric ion-exchangersTreatment of material for improving their amphoteric ion-exchange properties
• B01J 47/014 - Ion-exchange processes in generalApparatus therefor in which the adsorbent properties of the ion-exchanger are involved, e.g. recovery of proteins or other high-molecular compounds
• G01N 21/31 - Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry

Abstract

Micro-nano materials, products obtained by covalently modifying the surfaces of micro/nano materials with hydrophilic materials, and methods for making the same. The micro/nano materials on the surfaces have carboxyl groups or/and pro-carboxyl groups which are converted into their active esters. The products are covalently modified by forming amide bonds between the active esters on the surfaces and the modification agents; where the modification agents are hydrophilic compounds and/or hydrophilic polymers bearing primary and/or secondary aliphatic amines. Monomers bearing carboxyl groups and/or pro-carboxyl groups are used to produce an adequate number of carboxyl groups and/or pro-carboxyl groups on the surface of a polymer material to be modified. The carboxyl groups and/or pro-carboxyl groups are converted into active esters. A reasonably-sized modification agent bearing primary and/or secondary amines, zwitterions and hydrophilic linear spacer arms is used to form amide bonds and obtain a covalently modified surface layer.

IPC Classes  ?

• C07C 269/04 - Preparation of derivatives of carbamic acid, i.e. compounds containing any of the groups the nitrogen atom not being part of nitro or nitroso groups from amines with formation of carbamate groups
• C07C 231/12 - Preparation of carboxylic acid amides by reactions not involving the formation of carboxamide groups
• C08G 81/02 - Macromolecular compounds obtained by interreacting polymers in the absence of monomers, e.g. block polymers at least one of the polymers being obtained by reactions involving only carbon-to-carbon unsaturated bonds
• C08F 220/58 - Amides containing oxygen in addition to the carbonamido oxygen
• C08F 222/38 - Amides
• C08F 8/32 - Introducing nitrogen atoms or nitrogen-containing groups by reaction with amines
• C07C 227/12 - Formation of amino and carboxyl groups
• C07C 227/16 - Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof by reactions not involving the amino or carboxyl groups
• C07C 269/06 - Preparation of derivatives of carbamic acid, i.e. compounds containing any of the groups the nitrogen atom not being part of nitro or nitroso groups by reactions not involving the formation of carbamate groups
• C07C 303/04 - Preparation of esters or amides of sulfuric acidsPreparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof by substitution of hydrogen atoms by sulfo or halosulfonyl groups
• C07C 303/32 - Preparation of esters or amides of sulfuric acidsPreparation of sulfonic acids or of their esters, halides, anhydrides or amides of salts of sulfonic acids
• C07C 319/14 - Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides
• C07C 231/08 - Preparation of carboxylic acid amides from amides by reaction at nitrogen atoms of carboxamide groups
• C07D 207/40 - 2,5-Pyrrolidine-diones
• C07C 67/08 - Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
• C08G 65/332 - Polymers modified by chemical after-treatment with organic compounds containing oxygen containing carboxyl groups, or halides or esters thereof
• C08G 65/333 - Polymers modified by chemical after-treatment with organic compounds containing nitrogen
• C08G 65/334 - Polymers modified by chemical after-treatment with organic compounds containing sulfur