Oleogels Of Olive Oil And Soybean Oil For Topical Drug Delivery: A Comparative Analysis

Objective: The objective of the present investigation was to develop olive and soybean oil-based oleogels with Span 40 and/or Tween 80 (as gelator and/or surfactant) and determine the critical gelator concentration (CGC), characterise and compare the rheological, thermal properties and drug release profile of the gels formed for topical delivery. Methods: Olive and soybean oil-based Span 40 and Span 40/Tween 80 oleogel formulations were prepared by solid fiber mechanism and subjected to organoleptic evaluation, FT-IR spectroscopy, thermal analysis, rheological study, kinetic modeling of gelation and drug release. Results: The critical gelator (Span 40) concentration was found to be lower for olive oil (12% w/v) and depend on the type of oil. Tween 80 reduced CGC of soybean oleogels only. Soybean oil-based oleogel containing 18% w/v Span 40 was found to form more flexible, less viscous and thermally less stable formulation with better release of paracetamol as evident from lower melt flow index, Tg value, lower β and higher α value compared to olive oil-based oleogel with 12% w/v Span 40 (CGC). Surfactant addition can be assumed to modify the microarchitecture of the oleogels to a great extent to produce more flexible and thermally stable gels with even better drug release profile. Span-Tween based soybean oleogel formed a gel-matrix whereas matrix in olive oil-based oleogels containing Span only became slightly flexible to release the drug in zero-order fashion on the addition of surfactant cogelator. Conclusion: Nature of oil exerts profound influence on the rheological, thermal and release profile of oleogels containing Span 40 as gelator and/or Tween 80 as surfactant cogelator.

Design and Optimization of the Formulation and Technology of Theophylline Gel Matrix Sustained-release Tablets Based on QbD Concept / 中国药房

OBJECTIVE： To design and optimize the formulation and technology of Theophylline hydrophilic gel matrix sustained-release tablets （self-made sustained-release tablets for short） based on the concept of “Quality by Design” （QbD）. METHODS： Diluent type， tablet diameter， the property of adhesive （ratio of different adhesive types）， the amount of adhesive were regarded as critical process parameters （CPPs）. Similarity factor of dissolution curves of self-made Theophylline sustained-release tablets and reference preparation and its accumulative release rate at different time points were regarded as critical quality attributes （CQAs）. L18（34） orthogonal tablet was adopted for design and trial， and secondary polynomial regression model was established. By using Modde 12.0 software， the design space and its acceptable range （PAR） were calculated through the optimal model. The optimal formulation and technology of Theophylline sustained-release tablets was determined， and validation test and Monte Carlo simulation verification were conducted. RESULTS： The optimal model with good coincidence， accuracy， validity and reproducibility was obtained， which could better fit the relationship between CQAs and CPPs. The design space and PAR value were obtained by further calculation （The optimum value of diluent was lactose； tablet diameter was 9.07-9.33 mm， and the optimal value was 9.20 mm； ratio of HPMC K4M to HPMC was 0.50-0.83， and the optimal value was 0.80； total amount of HPMC was 0.036 0-0.041 3 g per tablet， and the optimal value was 0.038 g per tablet）. The optimal formulation and technology included that ratio of theophylline， HPMC K4M and HPMC K100M were 50％， 15.48％ and 3.87％， respectively； the rest was filled with lactose and the diameter of the tablet was 9.20 mm. The results of validation confirmed that self-made Theophylline sustained-release tablets had similar in vitro release behavior compared with reference preparation. CONCLUSIONS： Based on the concept of QbD， the formulation and technology of Theophylline sustained-release tablets can meet the requirements of design， and the CPPs can be adjusted within the PAR range to meet the requirements of CQAs. This shows that the QbD concept is scientific and effective in the design and optimization of the formulation and technology of sustained and controlled release preparations.

Application of Mixture Uniform Design in Optimizing the Proportion and Releasing Mechanism Study of GA and GB Hydrophilic Gel Matrix Tablets / 中国中医药信息杂志

Objective To optimize the prescription of GA and GB hydrophilic gel matrix tablets; To study the in vitro release mechanism. Methods On the basis of the results of the mono-factor investigation, mixture uniform design was used to optimize the handicraft molding prescription of GA and GB hydrophilic gel matrix tablets. The release mechanism was investigated by the vitro of the GA and GB hydrophilic gelmatrix tablets to accumulate releasing rate to conduct linear fitting. Results The optimized prescription of GA and GB hydrophilic gel matrix tablets was: powder: HPMC: lactose=23:24:53. Conclusion Mixture uniform design can be used to optimize the prescriptions of GA and GB hydrophilic gel matrix tablets, and the results are accurate. The hydrophilic gelmatrix tablets release medicine by non-Fick mechanism, and the medicine release is in accordance with zero-order.

A Five-Year Stability Study of Controlled-Release Diltiazem Hydrochloride Tablets Based on Poly(Ethylene Oxide).

The aim of this study is to investigative the stability of poly(ethylene oxide) (PEO) matrix tablets containing diltiazem hydrochloride (DTZ) after five-year storage at room temperature. DTZ matrix tablets containing different molecular weights (MW) of PEO and electrolytes (sodium carbonate anhydrous Na2CO3, potassium chloride KCl and pentasodium tripolyphosphate anhydrous PSTPP) were prepared. The fresh and stored tablets were evaluated by DTZ content, in vitro drug release rates and kinetics as well as DSC. All the PEO’s matrix tablets showed no significant changes in release rate, kinetics and drug content. The release rates of DTZ following five-year storage were slightly increased as the MW of PEO increased from 900,000 to 8,000,000. Also, it was clear that the addition of electrolyte drastically slowed the release rates of DTZ from fresh and stored tablets. DSC thermograms and similarity factor (ƒ2) depicted good system stability for all stored tablets. This is the first five-year long-term stability study reported concerning DTZ/PEO matrix tablets with different MW, which proved its stability for several years. This study might throw light on the dramatic difference observed between this study and the reported data of accelerated stability testing under stress conditions found in the literature.

Buspirone Hydrochloride Sustained-release Tablets:Preparation and Release in Vitro / 中国药房

OBJECTIVE:To prepare buspiron hydrochloride sustained-release tablets and to study its release characterization in vitro and the factors affecting drug release.METHODS:Buspiron hydrochloride sustained-release tablets were prepared with hydroxypropyl methylcellulose(HPMC)as hydrophilic gel-matrix material and ethylcellulose(EC)as retarder by wet granulation.The impacts of releasing transmitters,contents of HPMC and EC,and viscosity on the drug release in vitro of the tablets were studied.RESULTS:For the prepared sustained release tablets,the 24h drug release amount was over 90%,and the drug release curve conformed to Higuchi equation.The more contents of HPMC and EC and the higher viscosity of HPMC in the tablets,the slower drug release velocity was obtained;but the viscosity of EC and the releasing transmitters had no significant impacts on the drug release velocity.CONCLUSION:With HPMC and EC as matrix materials,the 24h continuous drug release is available for buspirone hydrochloride sustained-tablets.

Formula and Preparation Technology of Gel Matrix Sustained Release Tablet of Nicotinic Acid / 中国药房

OBJECTIVE: To optimize the formula and preparation technology of gel-matrix sustained release tablet of nicotinic acid(GSTNA).METHODS: The formula of GSTNA was optimized by orthogonal experiment with the amount of hydrophilic gel-matrix material HPMC(K15M,E15-LV) and that of adjuvant calcium hydrogen phosphate(CHP) as factors and with the in vitro release rates as index.Meanwhile,the verification test on the intra-and inter-batch release rates of the samples was performed.RESULTS: The optimum formula could be seen as follows: the ratios of HPMC(K15M,E15-LV) and CHP were 4%,40% and 25% respectively.The GSTNA prepared in this formula achieved a sustained drug release of up to 12 h,and both the intra-batch homogenicity and the inter-batch reproducibility were satisfactory.CONCLUSION: The GSTNA is reasonable in formula and simple in preparation technology.