3D Printing Approaches for Transdermal Drug Delivery

The delivery of drugs with poor solubility in water is a grand challenge in the field of pharmaceutical technology. We will consider two approaches for delivering drugs with poor water solubility, including (a) piezoelectric inkjet printing of the drug on the surface of the microneedles in a microneedle array, and (b) matrix assisted pulsed laser evaporation of the drug on the surface of the microneedles in a microneedle array. For example, we evaluated the use of piezoelectric inkjet printing to deposit antifungal agents with poor water solubility on the surfaces of solid microneedles. Optical imaging, scanning electron microscopy, and Fourier transform infrared spectroscopy showed that inkjet printing produced a drug coating on the surfaces of the microneedles. <i>In vitro</i> studies showed that the drug-modified microneedles possessed antifungal activity. In another study, matrix assisted pulsed laser evaporation was used to deposit an antifungal antiparasitic agent on the surface of solid microneedles. The matrix assisted pulsed laser evaporation process involves laser ablation of a frozen solution that contains the drug in a volatile solvent. An <i>i</i><i>n vitro</i> study showed that the drug-modified microneedles possessed concentration-dependent antifungal activity. The results indicate that piezoelectric inkjet printing and matrix assisted pulsed laser evaporation may be useful for loading drugs on the surfaces of microneedles.