ABSTRACT

Recently, microneedles have emerged as an alternative to hypodermic needles. Microneedles combine the advantages from both hypodermic needles and transdermal patches since microneedles can deliver big molecule drugs through the epidermis without causing pain from the injection. Microneedles can be divided into four types, [1] solid microneedles, coated microneedles, dissolving microneedles, and hollow microneedles. Solid microneedles are designed to open holes on the skin, so drugs can be delivered into the body through the holes, while coated microneedles can release drugs that are coated on the microneedles after injection. Dissolving microneedles are made of dissolvable materials where the microneedles and the drugs are dissolved after injection. Hollow microneedles can release liquid drugs via the holes in them. Till now, several materials were used to produce microneedles, for example, poly (lactic-co-glycolic acid) (PLGA), polyglycolic acid (PGA), poly (l-lactic acid) (PLA) [2], maltose [3], stainless [4, 5], titanium [6] and ceramic [7]. However, dissolvable polymers such as PLGA, PGA and PLA are very expensive. Maltose microneedles are brittle and easy to dissolve in humid environments [3]. Moreover, the fabrication process for stainless, titanium and ceramic microneedles are complicated

and expensive. Therefore, there is a strong need to develop low-cost micro needles that are easy to fabricate within short processing time. This work aims to develop a fabrication process of plastic microneedles using polystyrene solution which could offer several advantages such as low cost, simple fabrication, and short processing time. Furthermore, the fabricated polystyrene microneedles can be modified to produce replicas of a microneedle master.