The influence of drug-excipient and drug-polymer interactions on butt adhesive strength of ranitidine hydrochloride film-coated tablets

The influence of fillers and polymeric films on adhesive strength of hydroxypropyl methylcellulose (HPMC) and Eudragit E100® films coated on ranitidine HCl tablets containing either spray-dried rice starch (SDRS) or lactose monohydrate as fillers after storage at 45°C/75% RH for four weeks was investigated by the use of butt adhesion technique. The adhesive strength of film-coated tablets of fillers without drug was found to slightly decrease after storage. In contrast, the adhesive strength of drug-containing film-coated tablets significantly reduced, the degree of which was higher for Eudragit E100® than HPMC. Physicochemical characterization by employing differential scanning calorimetry (DSC) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) revealed that the drug was obviously incompatible with lactose and possibly mild interaction with Eudragit E100® was suggested. The results indicated that the adhesive strength of film-coated tablets would be affected not only by the drug-excipient interaction, but also by the drug-polymeric film interaction.     

固化条件对环氧树脂胶黏剂粘合强度的影响

研究了不同固化条件(温度、湿度)以及反应物配比对环氧树脂胶黏剂粘合强度的影响。结果表明,在使用环氧树脂胶黏剂粘接橡胶与金属基体时,固化条件对其粘接效果产生了显著影响。当温度为25 ℃,环氧树脂胶黏剂在湿度小于55%时粘合强度较高,湿度过高,粘合强度会明显下降,说明过于潮湿的环境不利于环氧树脂胶黏剂的应用。当湿度为55%,环氧树脂胶黏剂在20~25 ℃时粘合强度较高,当温度升高或者降低至10 ℃时,粘合强度都会有明显下降。     

Influence of Tableting Forces and Lubricant Concentration on the Adhesion Strength in Complex Layer Tablets

The strength of adhesion in complex two-layer tablets is assessed using statistical methods with respect to the applied tableting forces for the first layer and for applying the second layer on the first, as well as regarding the fraction of the lubricant. These results, obtained on a single-punch tablet press, are compared with the results for three-layer tablets produced on a rotary press at production scale. The strongest negative influence on adhesion strength was exerted by the amount of lubricant in the central layer. As expected, compression forces for central-layer tableting also had a negative effect, whereas the compression forces for complex layer tableting exerted a positive effect on layer adhesion. The validity of the derived model equation was proved by experiments: It was shown that the adhesion strength in complex layer tablets produced in production scale can be predicted from laboratory-scale experiments. This makes optimization of the formulation and parameter settings at an early stage of development possible.