Determination of the mechanical properties of polymeric microneedles by micromanipulation

Precise characterization of the mechanical properties polymeric microneedles is crucial for their successful penetration into skin and delivery loaded active ingredients. However, most available strategies this purpose are based on compression whole patch, which only provide average rupture force needles can not give information variations across individual in patch. In study, we determined strength two types hyaluronic acid with or without model drugs using a micromanipulation technique. The applied as function displacement was recorded, used to determine displacement, force, then derive calculate normal stress-deformation curve, stress Young?s modulus microneedles. obtained data suggest that molecular weight polymer loading drug significantly affect behavior microneedles, provides foundation preparing sufficiently strong controlled delivery.