Electrical Characterization of Micron-Sized Chambers Used as a Depot for Drug Delivery

Implantable drug delivery devices have emerged as a quintessential therapeutic platform for curing chronic ailments that require enhanced and localized drug concentrations. A typical device encompasses an array of tiny reservoirs or chambers to store drug formulations before their release inside a biological milieu. With the recent progress in biocompatible and biodegradable materials, it has become readily possible to fabricate chambers for rapid and on-demand drug release. However, to deal with an emerging diagnostic and therapeutic conundrum, new paradigms are required to devise chambers with multifunctional capabilities. In this article, we present micrometer-sized chambers that are fabricated by a patterned film base to realize their structure in an array formation. The microchambers are fabricated from a polylactic acid matrix and modified with a range of conducting species using the layer-by-layer (LBL) assembly technique. For electrical response characterization of microchambers, a complementary split ring resonator (CSRR) is used to estimate the loss tangent. A proof of concept is also discussed that the conductive nature of microchambers can be envisioned to perform thermal therapy and drug delivery in response to electromagnetic radiations.