Abstract Gastroretentive bilayer tablets of calcium carbonate (CC) were developed using D-optimal mixture design. The effect of formulation factors such as levels of HPMC K100 M (X1), sodium bicarbonate (X2), and HPMC E15 LV (X3) on responses like floating lag time (R1) and release of CC at 1 h (R2) and 6 h (R3) was elucidated. The optimized formulations developed by numerical optimization technique were found to have short floating lag time (2.85 ± 0.98 min), minimum burst release (27.02 ± 1.18%), and controlled yet near complete release (88.98 ± 2.75%) at 6 h. In vivo radiographic studies in rabbits indicated that optimized batch displayed a mean gastric retention time (GRT) of 5.5 ± 1 h which was significantly prolonged (P < 0.05) compared to the conventional tablets that displayed a GRT of less than 1 h. The studies proved that the gastroretentive tablets can be a promising platform to improve bioavailability of nutrients having absorption window in upper gastrointestinal tract.

中文翻译：

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基于D-最优混合设计的碳酸钙胃滞留双层片的配方与优化

摘要 使用 D 最优混合物设计开发了碳酸钙 (CC) 胃滞留双层片。HPMC K100 M (X1)、碳酸氢钠 (X2) 和 HPMC E15 LV (X3) 等配方因素对浮动滞后时间 (R1) 和 1 小时 (R2) 和 6 小时 CC 释放等响应的影响h (R3) 被阐明。发现通过数值优化技术开发的优化配方具有较短的浮动滞后时间 (2.85 ± 0.98 min)、最小突释 (27.02 ± 1.18%) 以及在 6 h 时受控但接近完全释放 (88.98 ± 2.75%)。兔体内放射学研究表明，优化批次的平均胃滞留时间 (GRT) 为 5.5 ± 1 小时，与显示 GRT 小于 1 小时的传统片剂相比，该时间显着延长 (P < 0.05)。