Background: Low bioavailability of anti-diabetic drugs results in the partial absorption of the drug as they are mainly absorbed from the stomach and the lower part of the GIT. Drug bioavailability of anti-diabetic drugs can be significantly increased by prolonging gastric retention time through gastro-retentive dosage form such as floating microspheres.

Objective: The study was aimed to develop and characterize resin based floating microspheres of Repaglinide and Metformin for superior and prolonged maintenance of normoglycaemia in type-2 diabetes mellitus.

Methods: Repaglinide and metformin were complexed with amberlite resin; later resin complexed drug was encapsulated in Ethylcellulose floating microspheres. Floating microspheres were characterized for morphology, particle size, IR spectroscopy, DSC, in vitro release and buoyancy studies. Further, floating microspheres were tested for in vivo blood glucose reduction potential in Streptozocin- induced diabetic mice.

Results: Floating microspheres had a spherical shape and slightly rough surface with the entrapment efficiency in a range of 49-78% for metformin and 52-73% for repaglinide. DSC studies revealed that no chemical interaction took place between polymer and drugs. Floating microspheres showed good buoyancy behavior (P<0.05) and prolonged drug release as compared to plain drug (P<0.05). The blood glucose lowering effect of floating microspheres on Streptozocin induced diabetic rats was significantly greater (P<0.05) and prolonged (˃12h) and normoglycaemia was maintained for 6hr.

Conclusion: Floating microspheres containing drug resin complex were able to prolong drug release in an efficient way for a sustained period of time; as a result, profound therapeutic response was obtained.

背景：抗糖尿病药物的低生物利用度导致药物的部分吸收，因为它们主要从胃和胃肠道下部吸收。通过漂浮微球等胃滞留剂型延长胃内滞留时间，可以显着提高抗糖尿病药物的药物生物利用度。

目的：该研究旨在开发和表征瑞格列奈和二甲双胍的树脂基漂浮微球，用于更好和长期维持 2 型糖尿病患者的正常血糖。

方法：瑞格列奈和二甲双胍与琥珀树脂复合；后来树脂络合药物被包裹在乙基纤维素漂浮微球中。漂浮微球的特征在于形态、粒径、红外光谱、DSC、体外释放和浮力研究。此外，在链脲佐菌素诱导的糖尿病小鼠中测试了漂浮微球体的体内血糖降低潜力。

结果：漂浮微球呈球形，表面略粗糙，二甲双胍的包封率范围为 49-78%，瑞格列奈的包封率范围为 52-73%。DSC 研究表明聚合物和药物之间没有发生化学相互作用。与普通药物相比，漂浮微球表现出良好的浮力行为（P<0.05）和药物释放时间延长（P<0.05）。漂浮微球对链脲佐菌素诱导的糖尿病大鼠的降血糖作用显着增强（P<0.05）并延长（˃12h），正常血糖维持6小时。

结论：含有药物树脂复合物的漂浮微球能够有效延长药物释放时间；结果，获得了深刻的治疗反应。