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Effective stroke recovery therapeutics remain limited. Stem cell therapies have yielded promising results, but the harsh ischemic environment of the post‐stroke brain reduces their therapeutic potential. Previously, a conductive polymer system that enables stem cell delivery with simultaneous electrical modulation of the cells and surrounding neural environment is developed. This wired conductive polymer system proved efficacious in optimizing ideal conditions for stem cell mediated motor improvements in a rodent model of stroke. To further enable preclinical studies and enhance translational potential, a method to improve this system by eliminating its dependence upon a tethered power source is identified. A wirelessly powered, electrically conductive polymer system that eases therapeutic application and enables full mobility is herein developed. As a proof of concept, it is demonstrated that the wirelessly powered system is able to stimulate neural stem cells in vitro, as well as in vivo in a rodent model of stroke. This system modulates the stroke microenvironment and increases the production of endogenous stem cells. In summation, this novel, wirelessly powered conductive polymer system can serve as a mobile platform for a wide variety of therapeutics involving electrical stimulation. [ABSTRACT FROM AUTHOR]

Hyaluronan (HA) is a naturally occurring glycosaminoglycan widely researched for its use as a biomaterial in tissue engineering, drug delivery, angiogenesis, and ophthalmic surgeries. The mechanical properties of this biomaterial can be altered to a required extent by chemically modifying the pendant reactive groups. However, derivatizing these polymers to a predetermined extent has been the Achilles heel for this process. In this study, we have investigated the factors controlling the derivatization of the carboxyl moieties of HA with amine containing thiol, cystamine dihydrochloride (Cys), via carbodiimide crosslinking chemistry. We used fractional factorial design to screen and identify the significant factor(s) affecting the reaction, and response surface methodology (RSM) to develop a model equation for predicting the degree of thiolation of HA. Also, we analyzed the reaction mechanism for potential side reactions. We observed that N-(3-dimethylaminopropyl)- N′-ethylcarbodiimide hydrochloride (EDC) (mole ratio with repeat unit of HA) is the significant factor controlling the degree of amidation. The quadratic equations developed from RSM predict the formulation for a desired degree of amidation of HA and percentage of potential side product. Hence, derivatizing HA to a predetermined extent with minimal side product can be achieved using the statistical design of experiments. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103: 2300-2308, 2015. [ABSTRACT FROM AUTHOR]