Formulation and evaluation of a salted-out isoniazid-loaded nanosystem

AAPS PharmSciTech. 2008;9(1):174-81. doi: 10.1208/s12249-007-9016-6. Epub 2008 Jan 25.

Abstract

The purpose of this study was to develop a drug-loaded nanosystem that has the ability to achieve flexible yet rate-controlled release of model drug isoniazid (INH) employing either an aqueous or emulsion-based salting-out approach. Formulation conditions were aimed at reducing the polymeric size with subsequent rate-modulated INH release patterns from the polymeric nanosystem. The emulsion-based salted-out nanosystems had particle sizes ranging from 77-414 nm and a zeta potential of -24 mV. The dispersant dielectric constant was set at 78.5 and a conductivity of 3.99 mS/cm achieved. The reduced nanosystem size of the aqueous-based approach has demonstrated an intrinsically enhanced exposure of methacrylic acid-ethyl acrylate to zinc sulphate which was employed as a crosslinking reagent. This resulted in robustly interconnected polymeric supports in which INH was efficiently embedded and subsequently released. The multi-layer perceptron data obtained showed that the aqueous and emulsion-based salting out approaches had Power (law) (MSE = 0.020) and Linear (MSE = 0.038) relationships, respectively. Drug release from the nanosystems occurred in two phases with an initial burst-release in aqueous-based nanosystems (30-100%) and significantly lower bursts observed in emulsion-based nanosystems (20-65%) within the first 2 h. This was followed by a gradual exponential release phase over the remaining 12 h. The nanosystems developed demonstrated the ability to control the release of INH depending on the formulation approach adopted.

MeSH terms

  • Antitubercular Agents / administration & dosage
  • Antitubercular Agents / chemistry
  • Delayed-Action Preparations / chemistry*
  • Diffusion
  • Drug Compounding / methods*
  • Drug Evaluation, Preclinical
  • Isoniazid / administration & dosage
  • Isoniazid / chemistry*
  • Materials Testing
  • Nanostructures / chemistry*
  • Nanostructures / ultrastructure*
  • Particle Size
  • Polymethacrylic Acids / chemistry*
  • Salts / chemistry

Substances

  • Antitubercular Agents
  • Delayed-Action Preparations
  • Polymethacrylic Acids
  • Salts
  • Isoniazid