MICRONEEDLES AND METHODS FOR MICROINFUSION

摘要

Methods and devices are provided for delivering a drug to or withdrawing a fluid from a biological tissue, such the skin, sclera, cornea, and conjunctiva. One method includes the steps of inserting at least one microneedle into the biological tissue; partially retracting the at least one microneedle from the tissue; and then delivering at least one drug formulation into the biological tissue via the partially retracted at least one microneedle. The microneedle deforms and penetrates the biological tissue during the insertion step, and the retraction step at least partially relaxes the tissue deformation while maintaining at least part of the tissue penetration, facilitating drug delivery or fluid withdrawal.