Subsecond Codetection of Dopamine and Estradiol at a Modified Sharkfin Waveform

17β-Estradiol (E2) is a ubiquitously
expressed hormone that
is active in a wide range of neuroprotective and regenerative roles
throughout the brain. In particular, it is a well-known dopamine (DA)
regulator and is responsible for modulating the expression of dopaminergic
receptors and transporters. Recent studies point to E2 release occurring
on a rapid time scale and having impacts on DA activity within seconds
to minutes. As such, tools capable of monitoring the release of both
E2 and DA in real time are essential for developing an accurate understanding
of their interactive roles in neurotransmission and regulation. Currently,
no analytical techniques capable of codetection of both analytes with
high sensitivity, spatiotemporal resolution, extended monitoring,
and minimal tissue damage exist. We describe a modified waveform using
fast-scan cyclic voltammetry that is capable of low nanomolar detection
of both DA and E2 on a subsecond time scale. Both analytes have limits
of detection at or below 30 nM and high sensitivity: 11.31 ±
0.55 nA/μM for DA and 9.47 ± 0.36 nA/μM for E2. The
waveform is validated in a tissue matrix, confirming its viability
for measurement in a biologically relevant setting. This is the first
method capable of codetection of fluctuations in DA and E2 with the
temporal, spatial, and sensitivity requirements necessary for studying
real-time neurochemical signaling.