Detachable Silicon Microneedle Stamps for Allergy Skin Prick Testing

We report on the fabrication and application of novel silicon microneedle chips for allergy skin prick testing. Due to the mask layout the needle chips can be directly detached from the wafer after their double-sided fabrication process. Silicon wafers with a total of 117 chips implementing various designs are fabricated. The chip center features a hole with a diameter of 0.5 mm into which a 25-gauge hypodermic needle can be easily inserted to directly detach the chips from the wafer without dicing. This enables the disposable microneedle chips to be handled without harming the needle structures. Skin prick tests performed with the microneedle stamps showed excellent results in comparison with common lancet pricking.