Abstract: The present disclosure discloses a fluorescent starch nanocrystal and a preparation method and application thereof. Mainly based on the character that starch nanocrystal has an active hydroxyl group on the surface, the present disclosure introduces fluorescein isothiocyanate into the surface of the starch nanocrystal in the form of stable covalent bonds through a two-step chemical modification method: silane coupling and electrophilic addition of fluorescein, so as to prepare the starch nanocrystal with fluorescent properties. The preparation process of the present disclosure is simple and easy to operate, uses cheap and readily available raw materials, involves low cost, and allows the non-fluorescent starch nanocrystal to produce significant fluorescent properties without affecting the properties of the starch nanocrystal itself, thereby expanding the application of starch.

Abstract: The present disclosure discloses a triple-responsive starch-based microgel and a preparation method thereof. The present disclosure prepares C6 oxidized starch and PNIPAM semi-interpenetrating network microgel, namely the triple-responsive starch-based microgel, mainly with pH sensitive C6 oxidized starch and temperature sensitive NIPAM (N-isopropylacrylamide) as raw materials, and using an inverse emulsion polymerization method. The triple-responsive starch-based microgel according to the present disclosure is a spherical particle with the particle diameter of 15-25 ?m, has pH, temperature and ionic strength-sensitivity, good biocompatibility and biodegradability, and can be widely used in the fields of nutrient protection, controlled drug release, protein separation and purification and the like. Meanwhile, its preparation process is simple and controllable with mild reaction conditions, and is suitable for large-scale production.

Abstract: The present disclosure discloses a triple-responsive starch-based microgel and a preparation method thereof. The present disclosure prepares C6 oxidized starch and PNIPAM semi-interpenetrating network microgel, namely the triple-responsive starch-based microgel, mainly with pH sensitive C6 oxidized starch and temperature sensitive NIPAM (N-isopropylacrylamide) as raw materials, and using an inverse emulsion polymerization method. The triple-responsive starch-based microgel according to the present disclosure is a spherical particle with the particle diameter of 15-25 ?m, has pH, temperature and ionic strength-sensitivity, good biocompatibility and biodegradability, and can be widely used in the fields of nutrient protection, controlled drug release, protein separation and purification and the like. Meanwhile, its preparation process is simple and controllable with mild reaction conditions, and is suitable for large-scale production.

Abstract: The present disclosure discloses a fluorescent starch nanocrystal and a preparation method and application thereof. Mainly based on the character that starch nanocrystal has an active hydroxyl group on the surface, the present disclosure introduces fluorescein isothiocyanate into the surface of the starch nanocrystal in the form of stable covalent bonds through a two-step chemical modification method: silane coupling and electrophilic addition of fluorescein, so as to prepare the starch nanocrystal with fluorescent properties. The preparation process of the present disclosure is simple and easy to operate, uses cheap and readily available raw materials, involves low cost, and allows the non-fluorescent starch nanocrystal to produce significant fluorescent properties without affecting the properties of the starch nanocrystal itself, thereby expanding the application of starch.

Abstract: A method for fractionating dextrin, belonging to the technical field of food processing. In principle, the method for fractionating dextrin of the present invention is based on the fact that the dextrin is incompatible with polyethylene glycol in aqueous solution and a larger molecular weight of the dextrin results in more significant incompatibility with polyethylene glycol. Accordingly, the stepwise precipitation of dextrin components having a molecular weight from large to small may be realized by gradually increasing the concentration of polyethylene glycol by gradually adding polyethylene glycol to dextrin in aqueous solution.

Abstract: A method for fractionating dextrin, belonging to the technical field of food processing. In principle, the method for fractionating dextrin of the present invention is based on the fact that the dextrin is incompatible with polyethylene glycol in aqueous solution and a larger molecular weight of the dextrin results in more significant incompatibility with polyethylene glycol. Accordingly, the stepwise precipitation of dextrin components having a molecular weight from large to small may be realized by gradually increasing the concentration of polyethylene glycol by gradually adding polyethylene glycol to dextrin in aqueous solution.