Fig. 4: Supramolecular nanowires system comprising health-monitoring sensors.

a Device configuration of the transmission-based photoplethysmogram (PPG) sensor. b Photographs of the setup for the real-time heart-rate (HR) measurement based on the PTCDI-C8 nanowires vertical phototransistors. c Long-term measurement of the pulse signal measured from vertical phototransistors at resting condition.