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Related Concept Videos

Methods for Studying Drug Absorption: In vitro01:16

Methods for Studying Drug Absorption: In vitro

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In vitro experiments are crucial for understanding the transport and absorption of drugs through biological materials. These studies employ varied methods such as the diffusion cell method, the everted sac technique, and the everted ring technique.
The diffusion cell method uses a two-compartment cell, including a donor compartment with the drug solution, which simulates the environment where the drug is applied, and a receptor compartment with a buffer solution, which simulates the environment...
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Factors Influencing Drug Absorption: Pharmaceutical Parameters01:28

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Solid dosage forms such as tablets and capsules undergo rigorous manufacturing processes to ensure stability and effectiveness. Their dissolution and absorption properties are influenced significantly by the choice of excipients (inactive ingredients that serve various roles in the formulation), and the methodology applied during production. The manufacturing parameters, such as compression force and granulation techniques, significantly affect dissolution rates. Elevated compression forces...
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Theories of Dissolution: Diffusion Layer Model01:15

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Dissolution, the process by which drug particles dissolve in a solvent, is explained by the diffusion layer model, a theoretical framework that simulates the absorption of oral drugs and allows us to analyze experimental data.
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Methods for Studying Drug Absorption: In situ01:09

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In situ experiments, such as the Doluisio method and Single-Pass Perfusion technique, provide critical insights into drug uptake by simulating in vivo conditions for drug absorption.
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Dissolution kinetics, an essential aspect of oral drug delivery, is significantly influenced by the drug's particle size. According to the Noyes-Whitney dissolution model, the dissolution rate correlates directly with the drug's surface area. The larger the surface area, the higher the drug's solubility in water, leading to a faster drug dissolution rate. Reducing particle size increases the effective surface area, enhancing the dissolution process. Micronization and nanosizing are...
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The pharmacokinetic journey of drugs from solid oral dosage forms into systemic circulation is multifaceted. It begins with disintegration, a prerequisite ensuring a solid dosage form's subdivision into minute particles. Dissolution occurs next as these granulated entities solubilize in gastrointestinal fluids. This solubilization is crucial for the succeeding stage, permeation, which describes the traversal of the drug across the intestinal membrane and its subsequent entry into the blood...
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In vitro release testing method development for long-acting injectable suspensions.

Quanying Bao1, Xiaoyi Wang1, Yuan Zou2

  • 1University of Connecticut, School of Pharmacy, Storrs, CT 06269, USA.

International Journal of Pharmaceutics
|May 20, 2022
PubMed
Summary

Developing better in vitro release testing methods for long-acting injectable (LAI) suspensions is crucial. New methods using USP apparatus 2 with enhancer cells and USP apparatus 4 with semisolid adapters show improved performance for LAI drug products.

Keywords:
Depo-SubQ Provera 104®Float-A-LyzerIn vitro release testingLong-acting injectableMedroxyprogesterone acetateSuspensionsUSP apparatus

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Area of Science:

  • Pharmaceutical Sciences
  • Drug Delivery Systems
  • Biopharmaceutics

Background:

  • Long-acting injectable (LAI) suspensions require precise drug release control over extended periods (weeks to months) to prevent adverse effects.
  • Current US FDA-recommended in vitro release testing methods for LAIs have durations under two days, potentially limiting their utility for establishing in vitro-in vivo correlations (IVIVCs).

Purpose of the Study:

  • To develop and evaluate novel in vitro release testing methods for medroxyprogesterone acetate LAI suspensions with longer durations.
  • To identify methods that better correlate with in vivo drug release performance for LAIs.

Main Methods:

  • Three compositionally equivalent medroxyprogesterone acetate LAI suspensions were prepared with varying particle sizes, using Depo-SubQ Provera 104® as the reference listed drug.
  • Four in vitro release testing methods were investigated: USP apparatus 2 (with dialysis sacs, enhancer cells, or in-house devices) and USP apparatus 4 (with semisolid adapters).

Main Results:

  • USP apparatus 2 utilizing enhancer cells demonstrated good discriminatory ability and reproducibility.
  • USP apparatus 4 employing semisolid adapters also exhibited excellent discriminatory capacity and reproducibility for the tested LAI suspensions.
  • These two methods showed superior performance compared to other tested configurations.

Conclusions:

  • USP apparatus 2 with enhancer cells and USP apparatus 4 with semisolid adapters are promising methods for in vitro release testing of LAI suspensions.
  • These methods offer improved discriminatory ability and reproducibility, potentially enabling better IVIVC establishment for long-acting injectable drug products.