posted on 2024-02-21, 12:35authored byBlaise
J. Ostertag, Ayah J. Syeed, Alexandra K. Brooke, Kamya D. Lapsley, Evan J. Porshinsky, Ashley E. Ross
We
present an optimized synthetic method for repurposing
coffee
waste to create controllable, uniform porous carbon frameworks for
biosensor applications to enhance neurotransmitter detection with
fast-scan cyclic voltammetry. Harnessing porous carbon structures
from biowastes is a common practice for low-cost energy storage applications;
however, repurposing biowastes for biosensing applications has not
been explored. Waste coffee ground-derived porous carbon was synthesized
by chemical activation to form multivoid, hierarchical porous carbon,
and this synthesis was specifically optimized for porous uniformity
and electrochemical detection. These materials, when modified on carbon-fiber
microelectrodes, exhibited high surface roughness and pore distribution,
which contributed to significant improvements in electrochemical reversibility
and oxidative current for dopamine (3.5 ± 0.4-fold) and other
neurochemicals. Capacitive current increases were small, showing evidence
of small increases in electroactive surface area. Local trapping of
dopamine within the pores led to improved electrochemical reversibility
and frequency-independent behavior. Overall, we demonstrate an optimized
biowaste-derived porous carbon synthesis for neurotransmitter detection
for the first time and show material utility for viable neurotransmitter
detection within a tissue matrix. This work supports the notion that
controlled surface nanogeometries play a key role in electrochemical
detection.