Mechanistic Approach to Understanding the Influence of USP Apparatus I and II on Dissolution Kinetics of Tablets with Different Operating Release Mechanisms

A new mode of Thinfilm and Nanofiber for burst release of the drug for Alzheimer disease; A complete scenario from dispersible polymer to formulation methodology

Alzheimer's disease (AD) is usually caused intellectual deterioration which happened due to the degeneration of cholinergic neurons. Donepezil is employed for cholinesterase enzyme Inhibition (ChEI) to treat AD in a wider population. Over the years, researchers finding difficulties prompted through traditional dosage forms particularly in geriatric patience. To avoid swallowing difficulties brought about with the aid of the AD population, researchers majorly focused on oral thin-film technology (OTF). This technology strongly eliminates issues caused by solid oral dosage forms. It is one of the quality strategies to an alternate drug that is used in the first-pass metabolism or pre systematic metabolism. The solubility of the drug is a higher trouble and it can expand by way of lowering particle size. Nanofibers are the excellent desire to minimize the drug particles to the submicron stage and can increase the drug release rate drastically. It can be prepared by Electrospinning technology by incorporating polymeric material into poorly soluble drugs. Mostly natural and biodegradable polymers prefer in all pharmaceutical preparations. Polymers employed for oral delivery should be stable, possess mucoadhesive property, and should release the drug by diffusion, degradation, and swelling mechanism. The objective of the present review explains various thin-film and nanofiber formulations used for faster drug release in the treatment of Alzheimer's disease.

Studying Drug Release through Polymeric Controlled Release Formulations in United States Pharmacopoeia 2 Apparatus Using Multiphysics Simulation and Experiments

In vitro dissolution of oral drug formulations is often studied using the United States Pharmacopoeia (USP) apparatus. Although a well-stirred vessel or a perfect sink assumption is often employed in the modeling of in vitro dissolution in USP apparatus, such a limit is usually not realized in actual experimental conditions. The interplay of hydrodynamics in the vessel and the swelling and erosion of dosage forms often results in substantial deviations from the dissolution behavior obtained under perfect sink approximation. We develop a multiphysics model of drug release from controlled release tablets of polymeric excipients with active pharmaceutical ingredients (APIs). Simulations are performed in COMSOL for the USP 2 (paddle) apparatus and the effects of stirring speed, drug loading, erosion rate, and polymer swelling and erosion are analyzed in detail. We demonstrate that the drug release phenomena can be conveniently interpreted using the Weibull equation to fit the simulation results. This is further confirmed using drug release experiments performed on mechanically compressed tablets of naproxen sodium as the API with poly-methyl-methacrylate-co-methacrylic acid as the excipient. We show that the API-to-polymer ratio may be varied to obtain different regimes of controlled release.

Experimental determination of the velocity distribution in USP Apparatus 1 (basket apparatus) using Particle Image Velocimetry (PIV)

The USP Apparatus 1 (basket apparatus) is commonly used to evaluate the dissolution performance of oral solid dosage forms. The hydrodynamics generated by the basket contributes, in general, to the dissolution rate and hence the dissolution results. Here, the hydrodynamics of Apparatus 1 was quantified in a vessel filled with 900-mL de-ionized water at room temperature by determining, via Particle Image Velocimetry (PIV), the velocity profiles on a vertical central plane and on 11 horizontal planes at different elevations at three different basket agitation speeds. The flow field was dominated by the tangential velocity component and was approximately symmetrical in all cases. Despite all precautions taken, small flow asymmetries were observed in the axial and radial directions. This appears to be an unavoidable characteristic of the flow in Apparatus 1. The magnitudes of the axial and radial velocity components varied with location but were always low. A small jet was seen emanating radially near the top edge of the basket. Velocities typically scaled well with increasing agitation speed in most regions of the vessel except for a region directly below the basket. The results of this work provide a major insight into the flow field inside the USP Apparatus 1.

Surfactant-Free Glibenclamide Nanoparticles: Formulation, Characterization and Evaluation of Interactions with Biological Barriers

PURPOSE

The aim of this work was to formulate and characterize surfactant-free glibenclamide nanoparticles using Eudragit RLPO and polyethylene glycol as sole stabilizer.

METHODS

Glibenclamide nanoparticles were obtained by nanoprecipitation and evaluated in terms of drug content, encapsulation efficiency, apparent saturation solubility, drug release profile, solid state and storage stability. The influence of different stirring speed on the particle size, size distribution and zeta potential of the nanoparticles was investigated. The nanoparticle biocompatibility and permeability were analyzed in vitro on Caco-2 cell line (clone HTB-37) and its interaction with mucin was also investigated.

RESULTS

It was found that increasing the molecular weight of polyethylene glycol from 400 to 6000 decreased drug encapsulation, whereas the aqueous solubility and dissolution rate of the drug increased. Particle size of the nanoformulations, with and without polyethylene glycol, were between 140 and 460 nm. Stability studies confirmed that glibenclamide nanoparticles were stable, in terms of particle size, after 120 days at 4°C. In vitro studies indicated minimal interactions of glibenclamide nanoparticles and mucin glycoproteins suggesting favorable properties to address the intestinal mucus barrier. Cell viability studies confirmed the safety profile of these nanoparticles and showed an increased permeation through epithelial cells.

CONCLUSION

Taking into consideration these findings, polyethylene glycol is a useful polymer for stabilizing these surfactant-free glibenclamide nanoparticles and represent a promising alternative to improve the treatment of non-insulin dependent diabetes.

Small volume method for drug release screening using ultrasonic agitation

Drug release testing plays a major role along all parts of the dosage form development and manufacturing process. However, official methods to perform this type of testing are often resource intensive and require highly specialized facilities. Affordable and accessible methods for studying drug release behavior are currently lacking. This work presents a small volume approach to solid dissolution and drug release testing of solid dosage forms using ultrasonic agitation. Cavitation and acoustic streaming were generated by a microprobe horn delivering a 40 kHz acoustic signal into a 50 mL test vessel. These two phenomena resulted in breakdown of and release of drug from tablet samples. Prednisone Performance Verification Tablets were used as model tablets to study the effect of system parameters on the drug release process. The effects of these parameters on the acousto-hydrodynamic environment were studied using streak photography and hydrophone measurements. Drug release behavior showed a slow/fast threshold transition separated by a highly variable regime as a function of the system parameters. Observations from drug release experiments and results from acoust-hydrodynamic characterization experiments suggested that this transition is dominated by acoustic streaming. This method represents a screening method to probe relative differences in dosage form composition and acts as a complimentary approach to official testing methods. The small volume format of this test has potential applications in the study of drug release properties from low-dose and novel solid dosage forms as well as reduced cost and increased accessibility of release testing for post-manufacturing tablet quality screening, a current need in low- and middle-income countries.