A novel electrostatic dry powder coating process for pharmaceutical dosage forms: immediate release coatings for...

Area of Science:

• Pharmaceutical Technology
• Materials Science

Background:

• Traditional pharmaceutical coating methods often involve aqueous or solvent-based systems.
• These methods can be limited by drying times, environmental concerns, and potential drug degradation.

Purpose of the Study:

• To develop and evaluate a novel electrostatic dry powder coating process for pharmaceutical solid dosage forms.
• To assess the feasibility of applying immediate-release coating compositions using this new technique.

Main Methods:

• An electrostatic dry powder coating process was established in a pan coater system.
• Tablet cores were treated with a liquid plasticizer to enhance conductivity and lower the glass transition temperature of the coating polymer.
• Charged coating particles (Opadry® AMB and Eudragit® EPO) were electrostatically sprayed onto tablet cores.
• Coating film formation was achieved through curing at acceptable processing temperatures.

Main Results:

• The electrostatic dry powder coating process successfully applied two immediate-release coating compositions.
• Tablet core conductivity was significantly increased, and particle deposition was enhanced.
• Scanning Electron Microscopy (SEM) confirmed the formation of a coalesced coating film.
• The resulting coated tablets exhibited smooth surfaces, uniform coatings, and comparable release profiles to uncoated cores.

Conclusions:

• The developed electrostatic dry powder coating technique is a viable alternative to conventional aqueous or solvent-based coating processes.
• This novel method offers potential advantages in efficiency and formulation flexibility for pharmaceutical solid dosage forms.