Biology subjects

Seo, J.-W.

Publications and source records attributed to Seo, J.-W..

2 recordsLinked to original sources

bioRxiv2021

Real-time monitoring of drug pharmacokinetics within tumor tissue in live animals

The efficacy and safety of a chemotherapy regimen fundamentally depends on its pharmacokinetics. This is currently measured based on blood samples, but the abnormal vasculature and physiological heterogeneity of the tumor microenvironment can produce radically different drug pharmacokinetics relative to the systemic circulation. We have developed an implantable microelectrode array sensor that can collect such tissue-based pharmacokinetic data by simultaneously measuring intratumoral pharmacokinetics from multiple sites. We employ gold nanoporous microelectrodes that maintain robust sensor performance even after repeated tissue implantation and extended exposure to the tumor microenvironment. We demonstrate continuous in vivo monitoring of concentrations of the chemotherapy drug doxorubicin at multiple tumor sites in a rodent model, and demonstrate clear differences in pharmacokinetics relative to the circulation that could meaningfully affect drug efficacy and safety. This platform could prove valuable for preclinical in vivo characterization of cancer therapeutics, and may offer a foundation for future clinical applications.

bioengineering↗

bioRxiv2021

Accelerated electron transfer in nanostructured electrodes improves the sensitivity of electrochemical biosensors

Electrochemical biosensors hold the exciting potential to integrate molecular detection with signal processing and wireless communication in a miniaturized, low-cost system. However, as electrochemical biosensors are miniaturized to the micron scale, their detection sensitivity degrades precipitously, thereby greatly reducing their utility in the context of molecular diagnostic applications. Studies have reported that nanostructured electrodes can greatly improve electrochemical biosensor sensitivity, but the underlying mechanism remains poorly understood, thus making it difficult to fully exploit this phenomenon to improve biosensor performance. In this work, we propose and experimentally validate a novel mechanism in which electron transfer is physically accelerated within nanostructured electrodes due to reduced charge screening, resulting in enhanced sensitivity. We show that this mechanism can be exploited to achieve up to 24-fold increase in signal and nearly four-fold lower limit-of-detection relative conventional planar electrodes. This accelerated electron transfer mechanism should prove broadly applicable for improving the performance of electrochemical biosensors.

bioengineering↗