Search

The aim of the work presented is to prepare a controlled-release hydrophilic matrix tablet (CMT) controlling release of highly water-soluble drug applying pure combination of high- and low-Mw PEO as matrix materials, to avoid the lag time of drug release, and to overcome incomplete release in later stages. The influences of types and amounts of different Mw PEOs used, drug loading, pH of release medium and agitation rate on drug release were evaluated. The study of uptake and erosion of matrix was conducted and mechanism of improving drug release was discussed.In vivopharmacokinetics of the CMT and reference preparation self-made controlled-release osmotic pump tablets (COPT) were performed in beagle dogs. The optimized formulation containing 43% PEO WSR 303 and 32% PEO N750 showed a zero order release from 1 h to 12 h.In vivoresults demonstrated that the CMT had similar AUC0-48 handCmaxwith the COPT but smallerTmaxthan the COPT and provided a more stable therapeutic concentration compared to the COPT. In conclusion, hydrophilic matrix tablet combining only different Mw PEOs as matrix materials had very good potential to be developed into a controlled-release drug delivery system for highly water-soluble drug. Besides, its manufacturing processes were succinct which would be preferable for modern medicine industry. [ABSTRACT FROM AUTHOR]

Dipyridamole (DIP), having a short biological half-life, has a narrow absorption window and is primarily absorbed in the stomach. So, the purpose of this study was to prepare controlled-release floating (CRF) tablets of dipyridamole by the dry-coated method. The influence of agents with different viscosity, hydroxypropylmethylcellulose (HPMC) and polyvinylpyrollidon K30 (PVP K30) in the core tablet and low-viscosity HPMC and PVP K30 in the coating layer on drug release, were investigated. Then, a study with a three-factor, three-level orthogonal experimental design was used to optimize the formulation of the CRF tablets. After data processing, the optimized formulation was found to be: 80 mg HPMC K4M in the core tablet, 80 mg HPMC E15 in core tablet and 40 mg PVP K30 in the coating layer. Moreover, anin vitrobuoyancy study showed that the optimized formulation had an excellent floating ability and could immediately float without a lag time and this lasted more than 12 h. Furthermore, anin vivogamma scintigraphic study showed that the gastric residence time of the CRF tablet was about 8 h. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the fundamental properties of propranolol hydrochloride osmotic pump tablets coated by aqueous polymer dispersion, simultaneously exploring the in vitro and in vivo correlation of the tablet. The physicochemical properties and parameters of aqueous polymer dispersion membranes (SEM, water uptake, and water vapor transmission coefficient) were investigated. In addition, the release behavior and the in vitro release and in vivo absorption profiles of the tablets coated by aqueous polymer dispersion were investigated by comparing with propranolol hydrochloride osmotic pump tablets coated by an organic solvent. Results showed that the similarity factor ( f ) between cellulose acetate-coated tablet and Eudragit-coated tablet was 78.1, and f between cellulose acetate-coated tablet and Kollicoat-coated tablet was 77.6. The linear IVIVC of Eudragit-coated and Kollicoat-coated osmotic pump tablets was determined, which confirmed excellent correlation between the absorption in vivo and the drug release in vitro. Consequently, the membrane coated by aqueous polymer dispersion or organic solvent has similar in vitro release rates of controlled release. Also, compared with organic solvent coating, aqueous polymer dispersion has numerous advantages, such as reduced toxicity and no environmental damage. Therefore, the aqueous polymer dispersion technology has enormous potential as a replacement of organic solvent coating. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore the feasibility of combining fused deposition modeling (FDM) 3D printing technology with hot melt extrusion (HME) to fabricate a novel controlled-release drug delivery device. Glipizide used in the treatment of diabetes was selected as model drug, and was successfully loaded into commercial polyvinyl alcohol (PVA) filaments by HME method. The drug-loaded filaments were printed through a dual-nozzle 3D printer, and finally formed a double-chamber device composed by a tablet embedded within a larger tablet (DuoTablet), each chamber contains different contents of glipizide. The drug-loaded 3D printed device was evaluated for drug release under in vitro dissolution condition, and we found the release profile fit Korsmeyer–Peppas release kinetics. With the double-chamber design, it is feasible to design either controlled drug release or delayed drug release behavior by reasonably arranging the concentration distribution of the drug in the device. The characteristics of the external layer performed main influence on the release profile of the internal compartment such as lag-time or rate of release. The results of this study suggest the potential of 3D printing to fabricate controlled-release drug delivery system containing multiple drug concentration distributions via hot melt extrusion method and specialized design configurations. [ABSTRACT FROM AUTHOR]

Background: In recent years, controlled and sustained release drug delivery system has become the focus of pharmaceutical researchers. Some technologies aimed to develop the controlled and sustained release of the drug, which used to be administered several times a day and generate plasma concentration fluctuation. As all, a controlled drug release rate has always been a goal pursued by researchers. This paper introduced a controlled delivery hydrophilic matrix system, and evaluated their relevance between in vitro and in vivo behaviors., Methods: The matrix tablets were fabricated by direct powder compression method. Single-factor test and the orthogonal experimental design were used to find out the optimal formulation. And the in vivo pharmacokinetics study was also evaluated in this paper., Results: The amount of WSR N301 and low viscosity materials significantly affect the drug release. Compared with commercially available sustained-release tablets Diamicron®, the pharmacokinetics parameters of these matrix tablets exhibited similar blood profiles, and other parameters such as prolonged Tmax, Cmax, MRT and similar bioavailability. However, this matrix system showed unstable blood profiles in comparison with two-layer-core osmotic pump tablet. The IVIVC study suggested that there was a good correlation between absorption in vivo and drug release in vitro., Conclusion: Zero-order controlled drug release of hydrophilic matrix system has the simpler manufacture process. And it will be a promising system to control drug release. Due to the disadvantage of hydrophilic matrix tablets in vivo release, for further research the zero-order delivery of PEO matrix tablets system, some pharmaceutical technology are needed to decrease the influence of gastrointestinal peristalsis. Therefore, the study of polyethylene oxide hydrophilic matrix tablets provides a promising formulation for promoting the development of a drug delivery system., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)