Preparation and characterization of berberine hydrochloride gelatin microspheres
Berberine hydrochloride (BH), also known as berberine, is a yellow crystalline powder with an extremely bitter taste. It has anti-cancer, antibacterial, hypoglycemic, cholesterol lowering, and vasodilatory effects. Due to its significant antibacterial effect, it is commonly used to treat diseases such as bacterial dysentery and gastroenteritis, with definite therapeutic effects. But its taste is extremely bitter and patients have poor compliance. Making it into microspheres can improve the taste of the drug, mask its bitterness, and reduce the irritation of berberine hydrochloride on the gastric mucosa. Gelatin microspheres are widely used in the research of new drug formulations due to their advantages of biodegradability and low toxicity. Microsphere formulations also have sustained-release, improved stability, taste masking, and targeting effects. This experiment used the emulsification chemical cross-linking solidification method to prepare hydrophilic gelatin microspheres of berberine hydrochloride, optimized the preparation process, and conducted characterization analysis to investigate the release performance, in order to provide theoretical basis for the research of related formulations.

 

 

This study used emulsion chemical crosslinking method to prepare berberine hydrochloride microspheres, with a drug loading of 19.97% and an encapsulation efficiency of 67.71%. In vitro drug release showed slow drug release. DSC, XRD, and infrared spectroscopy analysis showed that berberine hydrochloride existed in an amorphous form in the microspheres, but the surface of the microspheres contained a small amount of berberine hydrochloride. Scanning electron microscopy observation of the appearance and morphology of microspheres revealed that they were round and smooth, with uniform size but adhesive bonding, which may be related to factors such as drying method, drying temperature, and drying speed. The next step of research will be to investigate drying conditions to improve the appearance and quality of gelatin microspheres.

The selection of appropriate emulsifiers and crosslinking agents during the preparation process has a significant impact on the roundness, size, and other properties of gelatin microspheres. In the preliminary experiment, it was found that Span-80 as an emulsifier had better emulsification effect than Twen-80 and mixed emulsifiers, and could obtain microspheres with better roundness. Therefore, Span-80 was selected as the emulsifier. The commonly used crosslinking and curing agents for gelatin microspheres are formaldehyde and glutaraldehyde. Through preliminary experiments, it was found that glutaraldehyde as the crosslinking and curing agent resulted in microspheres with small and round particle size, while formaldehyde caused significant adhesion and poor roundness in the prepared microspheres; And using glutaraldehyde as a curing agent does not require adjusting the pH value. It can react under neutral conditions and is easy to operate. Therefore, glutaraldehyde is chosen as the crosslinking curing agent.

The preparation of berberine hydrochloride gelatin microspheres using emulsion chemical crosslinking method is simple and feasible, requiring only one type of capsule material. The gelatin is biodegradable, low toxic, inexpensive and easy to obtain. The resulting berberine hydrochloride gelatin microspheres have a high drug loading capacity, high encapsulation efficiency, good stability, and good application prospects.