A novel approach for tailored medicines: Direct writing of Janus fibers

Recent explorations have shown potential drug delivery applications of random and aligned fibrous dosage forms (e.g. patches, dressings, films and inserts). In this study, novel controlled delivery dosage forms, comprising Janus fibers, are designed and fabricated using electrohydrodynamic (EHD) engineering. Model probe and active compound release is shown from dissimilar polymer systems (non-soluble and soluble in nature) which constitute towards Janus systems. Micron scaled aligned Janus fibers comprising polycaprolactone (PCL) and polyvinyl pyrrolidone (PVP) were engineered to host rhodamine B and acriflavine, respectively. The impact of various operating parameters (e.g. flow rate, collector speed, working distance and applied voltage) on resulting mean fiber diameter and shape were optimized. Tensile strain decreased from 116.5 ± 10.2% to 81.8 ± 9.5% upon the inclusion of the model compounds, while both PCL/PVP and PCL/PVP/dyes samples exhibited similar tensile strength (∼0.65 MPa). FTIR analyses demonstrates PCL/PVP blend behavior and successful incorporation of rhodamine B and acriflavine. Acriflavine release from PCL fibers spanned over a 4-day period, and release of rhodamine B from PVP fibers was just over 6 h. The results indicate the EHD direct-jetting technique enables the precise construction of drug loaded and aligned fibers in a single-step with minimal excipient usage for potential customized drug delivery.