34 results about "Longitudinal Relaxation Rate" patented technology

The invention discloses a gadolinium-doped copper sulfide nanoparticle based on a protein biological template and a preparation method thereof. The protein template is dissolved in PBS, configured into a solution with a concentration of 0.5-1.5mM, copper salt and gadolinium salt solution, and stirred Then add sodium hydroxide solution to adjust the pH to 8-12, then inject sulfur source, and react at 25°C-50°C; after dialysis and freeze-drying, GdCuS nanoparticle powder is obtained. The prepared GdCuS nanoparticles have a particle size of 6-10nm and are wrapped with protein on the outside. The photothermal conversion efficiency reaches 20%-30%, and the longitudinal relaxation rate r 1 =10mM·s ‑1 ‑18mM·s ‑1 . Higher heat will be generated under the irradiation of near-infrared light, and it is an ideal photothermal conversion agent and photoacoustic imaging contrast agent; the preparation steps of the invention are simple, and it is easy to prepare in large quantities; the reaction conditions are mild and energy consumption is reduced; the environmental compatibility is good , is a green synthetic process.

The invention discloses a contrast medium for fluorescent-magnetic resonance dual-mode targeting biological imaging and a preparation method thereof. The method comprises the following steps that 1, a chelating agent and a compound containing Gd3+ react in water to obtain a Gd3+ chelate solution; 2, citric acid and polyethyleneimine are dissolved into water, and then the Gd3+ chelate solution is added to be mixed; 3, the mixture obtained in the step 2 is dissolved and evaporated to dryness repeatedly, centrifuging is performed on the dissolved and dried products, a supernate is taken for dialysis in water to obtain a dialysis solution, and a dialysis solution is subjected to freeze-drying, and Gd doped carbon dots are obtained. Meanwhile, the invention further discloses a contrast medium for fluorescent-magnetic resonance dual-mode targeting biological imaging. The contrast medium is synthetized in an environment-friendly mode, is low in gadolinium content, promotes surface functionalization, and has the quite high longitudinal relaxation rate and the fluorescence quantum yield, and the good biological compatibility and blood compatibility.

The invention discloses a method for preparing a Gd3<+> magnetic resonance imaging contrast agent with graphene oxide serving as a carrier, and belongs to the technical field of preparation of medical materials. The method comprises the following steps of: 1) dispersing graphene oxide into distilled water to obtain a graphene oxide dispersing solution; 2) adding an alkaline substance and chloroacetic acid or sodium monochloroacetate to the graphene oxide dispersing solution, ultrasonically dispersing, centrifugally washing and processing, and dialyzing to obtain carboxylation graphene oxide; and 3) dispersing the carboxylation graphene oxide into the distilled water to obtain a carboxylation graphene oxide dispersing solution, adding an aqueous solution of gadolinium salt to the carboxylation graphene oxide dispersing solution, adding a DTPA (Diethylene Triamine Pentacetic Acid) aqueous solution after the stirring reaction is done, uniformly mixing to obtain a mixing solution, and dialyzing to obtain carboxylation graphene oxide with Gd3<+> loaded on the surface, thus obtaining the Gd3<+> magnetic resonance imaging contrast agent. The method is simple and feasible, and the Gd3<+> is firmly loaded; and the preparation magnetic resonance imaging contrast agent is high in water-borne dispersion stability and has high longitudinal relaxation rate.