US 12,214,057 B2
Graphene quantum dots-gadolinium ion chelate as magnetic resonance imaging contrast agent and preparation method thereof
Hong Bi, Hefei (CN); and Dong Wang, Hefei (CN)
Assigned to ANHUI UNIVERSITY, Hefei (CN)
Appl. No. 17/422,211
Filed by ANHUI UNIVERSITY, Hefei (CN)
PCT Filed Mar. 5, 2019, PCT No. PCT/CN2019/076939
§ 371(c)(1), (2) Date Jul. 12, 2021,
PCT Pub. No. WO2020/155286, PCT Pub. Date Aug. 6, 2020.
Claims priority of application No. 201910095524.6 (CN), filed on Jan. 31, 2019.
Prior Publication US 2022/0072161 A1, Mar. 10, 2022
Int. Cl. A61K 49/00 (2006.01); A61K 49/08 (2006.01); B82Y 5/00 (2011.01); B82Y 20/00 (2011.01); B82Y 30/00 (2011.01); B82Y 40/00 (2011.01); C01B 32/198 (2017.01); C09K 11/65 (2006.01)
CPC A61K 49/0002 (2013.01) [A61K 49/0019 (2013.01); A61K 49/085 (2013.01); C01B 32/198 (2017.08); C09K 11/65 (2013.01); B82Y 5/00 (2013.01); B82Y 20/00 (2013.01); B82Y 30/00 (2013.01); B82Y 40/00 (2013.01); C01P 2004/04 (2013.01); C01P 2004/64 (2013.01); C01P 2004/80 (2013.01); C01P 2006/60 (2013.01); C01P 2006/82 (2013.01)] 15 Claims
 
1. A method for preparing the graphene quantum dots-gadolinium ion chelate, comprising the following steps:
1) Preparing graphene oxide by using a Hummers method;
2) Weighing and dissolving the graphene oxide in deionized water to obtain a first solution, performing an ultrasonic treatment on the first solution, and then adding a predetermined amount of a strong oxidant for being fully dissolved to obtain a second solution, wherein the strong oxidant is a mixture of at least one of potassium persulfate, hydrogen peroxide, and hypochloric acid;
3) Adding 400-1,000 μL of a basic compound to the second solution to obtain a resulting solution, and then refluxing the resulting solution for 7-12 h at 70-120° C.;
4) After the resulting solution is refluxed, performing a purification and a drying on the resulting solution to obtain the graphene quantum dots;
5) Preparing the graphene quantum dots into a third solution with a predetermined concentration, wherein the graphene quantum dots are pure, and then adding a predetermined amount of a gadolinium chloride solution to perform a chelation reaction under predetermined conditions to obtain a solution after the chelation reaction; and
6) Performing a purification and a drying on the solution after the chelation reaction to obtain the graphene quantum dots-gadolinium ion chelate.