Inkjet printing as a novel medicine formulation technique

Area of Science:

• Pharmaceutical Technology
• Materials Science
• Drug Delivery

Background:

• Poorly water-soluble drugs like felodipine often require formulation strategies to enhance bioavailability.
• Molecular dispersion within polymers, such as polyvinyl pyrrolidone (PVP), is a common method to improve drug solubility.
• Ink-jet printing offers a precise and scalable method for formulating active pharmaceutical ingredients.

Purpose of the Study:

• To demonstrate the feasibility of using ink-jet printing to create drug formulations with controlled release properties.
• To investigate the molecular dispersion and drug-polymer interactions of felodipine with PVP.
• To characterize the drug release profiles from printed micro-formulations.

Main Methods:

• Formulations of felodipine and PVP in an ethanol-DMSO solvent mixture were prepared in various ratios.
• Piezoelectric ink-jet printing was used to deposit picoliter quantities of the formulation onto a hydrophobic substrate.
• Characterization involved atomic force microscopy, nano-thermal analysis, ATR-IR, and confocal Raman spectroscopy.

Main Results:

• Intimate molecular mixing of felodipine and PVP was confirmed within the printed micro-dots.
• Hydrogen bonding between felodipine and PVP was observed, indicating drug-polymer interaction.
• Nano-thermal analysis revealed a single glass transition point, dependent on drug concentration, signifying a homogeneous mixture.
• Confocal Raman microscopy visualized drug distribution and enabled characterization of drug release, which was tunable via drug loading.

Conclusions:

• Ink-jet printing is a viable technology for producing drug formulations with controlled release characteristics.
• The intimate mixing and drug-polymer interactions achieved through ink-jet printing can enhance drug bioavailability.
• This approach holds potential for scalable manufacturing of personalized dosage forms, including point-of-care applications.