Sustained release of ketoprofen from fibrous chitosan-poly(ɛ-caprolactone) membranes

Localized and targeted delivery of NSAIDs for treatment of inflammation: A review

IMPACT STATEMENT

This work provides an overview of research currently being done exploring potential drug delivery device strategies for NSAIDs as an alternative to systemic delivery. Commentary on this field is made in an attempt to aid future experimental design, enabling researchers to determine the drugs and delivery vehicles which are most advantageous for them to pursue, as well as suggestions to standardize the reporting of such future research.

Establishment of nerve growth factor gradients on aligned chitosan-polylactide /alginate fibers for neural tissue engineering applications

Nerve conduits containing aligned fibrous fillers with gradiently distributed signal molecules are essential for long-gap nerve repair. This study was to develop an approach for establishing nerve growth factor (NGF) gradients onto the aligned chitosan-polylactide (CH-PLA) fibers. CH-PLA containing 37wt% of PLA was spun into fibers using a wet-spinning technique. CH-PLA fibers showed much higher wet-state tensile strength, enhanced degradation tolerance and significantly lower swelling degree in comparison to chitosan fibers. The CH-PLA fibers with diameters from 40 to 60μm were selected and segmentally coated in bundles using NGF-contained alginate solutions to establish NGF gradients lengthwise along fibers. The diameter of resulting NGF-loaded CH-PLA/alginate fibers was well controlled within a range between 60 and 120μm. Calcium ion crosslinked alginate coating layers on fibers showed abilities to administer the sustainable NGF release in a gradient distribution manner for at least 5 weeks. NGF-induced neurite outgrowth of PC12 cells confirmed that bioactivity of NGF released from fibers was well retained.

Design of a Time-Controlled Pulsatile Release System for Propranolol Using the Dry-Coated Method: In Vitro and In Vivo Evaluation

The objective of this study was to design a time-controlled pulsatile release (TCPR) system containing propranolol (PNH) as an active pharmaceutical ingredient. Here, the developed dosage forms were coated with hydroxypropyl-methylcellulose (HPMC) and other excipients as barrier layer using dry-coated technology. The influence of HPMC, microcrystalline cellulose (MCC), and lactose in the outer coating and the coating weight on drug release were investigated. Then, a three-factor, five-level central composite design (CCD) and response surface method were used to optimize the formula of the coating. After data processing, the optimal prescription was found to be as follows: HPMC E50(X₁) 86.2 mg, MCC(X₂) 43.8 mg, and lactose (X₃) 21.3 mg in the coating. Moreover, the in vitro tests showed that the optimized formulation of TCPR had a lag time of 4 h followed by a 4-h drug release. Also, determination of the extent of erosion of the TCPR tablets revealed that the lag time is related to the coating erosion speed. The in vivo test in beagle dogs and comparison of the parameters for the TCPR tablets and reference preparations showed significant differences for T_max (7.83 ± 0.408 and 2 ± 0.00) and C_max (185.45 ± 28.561 and 587 ± 45.27 ng/ml) but no significant differences in the AUC_0-∞ (1757.876 ± 208.832 and 1779.69 ± 229.02 ng h/ml). These results demonstrated that the TCPR tablets successfully prolonged the lag time and controlled the release of propranolol.

A time-adjustable pulsatile release system for ketoprofen: In vitro and in vivo investigation in a pharmacokinetic study and an IVIVC evaluation

A time-adjustable pulsatile release system (TAPS) containing ketoprofen (KF) as an active pharmaceutical agent was developed having been designed for bedtime dosing and releasing drug in the early morning to control the symptoms of rheumatoid arthritis (RA). The formulation involved a tablet core (KF) and a control-release layer, and the coating membrane was composed of EC and Eudragit L100. A single-factor study, a central composite design and a response surface method were selected to optimize the formula and the optimum prescription was as follows: tablet core (KF 50mg, MCC 70mg, lactose 40mg, L-HPC 38mg), and film (EC 7.8g, Eudragit L100 4.2g, PEG 6000 1.8g in 95% alcohol each 200ml). The in vivo release behavior of the tablets was evaluated in Beagle dogs after a parallel oral administration of KF TAPS tablets and commercial KF capsules, when it was found that the KF TAPS tablets released the drug after a lag-time of 3.458h and the T_max was 5.833h. The relative bioavailability was 85.01%, and the two formulations were bioequivalent in terms of C_max and AUC_0-t and the in vitro- in vivo correlations indicated that test formulation had a good in vivo-in vitro correlation (r=0.9703). These results show that the novel drug delivery system (TAPS) has the potential to be used as a KF preparation with chronophamacokinetics characteristics.

Ibuprofen microencapsulation within acrylamide-grafted chitosan and methylcellulose interpenetrating polymer network microspheres: Synthesis, characterization, and release studies

This study deals with the development of interpenetrating polymer network (IPN) microspheres of acrylamide (AAm) grafted onto a chitosan (CS) backbone and methylcellulose (MC). Chitosan-graft-polyacrylamide (CS-g-PAAm) was synthesized by cerium (IV) ammonium nitrate-induced free radical graft polymerization. The grafting percentage was found to be 50.58%. The synthesized graft copolymer and MC were used to prepare microspheres by the water-in-oil (w/o) emulsion-crosslinking method, and crosslinked with glutaraldehyde (GA) as drug delivery matrices of ibuprofen (IBU). The release of IBU from microspheres decreased when the amount of CS-g-PAAm in the polymer matrix and amount of crosslinker added were increased, while it increased with the increase of the IBU/polymer ratio.