Graduate Studies


First Advisor

Ali Tamayol

Date of this Version


Document Type



A THESIS Presented to the Faculty of the Graduate College at the University of Nebraska in Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Mechanical Engineering and Applied Mechanics, Under the Supervision of Professor Ali Tamayol. Lincoln, Nebraska: April, 2019

Copyright 2019 Hossein Derakhshandeh


Chronic wounds are one of the most challenging complications of diabetes and are the leading cause of non-traumatic limb amputation. Despite the progress in identifying factors and promising in vitro results for the treatment of chronic wounds, their clinical translation has been limited. Given the range of disruptive processes necessary for wound healing, different pharmacological agents are needed at different stages of tissue regeneration. This requires the capability of wearable devices to deliver agents to critical layers of the epidermis with minimum invasiveness. Here, for the first time, I have engineered a programmable platform which is capable of actively delivering a variety of drugs with independent temporal profiles through miniaturized needle arrays (MNAs) into deeper layers of the wound bed. The delivery of vascular endothelial growth factor (VEGF) through the MNAs demonstrated that, in addition to the selection of suitable therapeutics, the delivery method and their spatial distribution within the wound bed is equally important. Administration of VEGF to chronic dermal wounds of diabetic mice using the programmable platform showed a significant increase in wound closure, re-epithelialization, angiogenesis, and hair growth when compared to standard topical delivery of therapeutics.

Advisor: Ali Tamayol