# A Sweat Cortisol Sensor Based on Gold-Modified Molecularly Imprinted Polymer

## TL;DR

A new portable sensor was developed to detect cortisol in sweat for real-time mental stress monitoring.

## Contribution

A gold-modified molecularly imprinted polymer sensor with high sensitivity and low detection limit for cortisol.

## Key findings

- The sensor has a linear detection range from 1 fM to 1 μM.
- It achieves an ultra-low detection limit of 0.4112 fM.
- The sensor offers high sensitivity of 15.518 nA∙lg(nM−1)∙cm−2.

## Abstract

Approximately 3.8% of the global population suffers from depressive disorders, posing a substantial public health challenge exacerbated by the COVID-19 pandemic due to widespread unemployment and prolonged social isolation. The difficulty in objectively quantifying psychological states underscores the need for effective stress assessment methods. Herein, we developed a portable electrochemical cortisol sensor (PECS) for accurate mental stress assessment. The PECS consists of a screen-printed carbon electrode decorated with gold nanoparticles and a molecularly imprinted polymer (MIP) synthesized via electropolymerization. The as-prepared PECS demonstrates a wide and linear detection range from 1 fM to 1 μM, an ultra-low detection limit of 0.4112 fM and a high sensitivity of 15.518 nA∙lg(nM−1)∙cm−2. This work provides new possibility of developing soft bioelectronics for non-invasive and real-time mental health monitoring.