University of Southampton Centre for Electronics Frontiers, Zepler Institute for Photonics and Nanoelectronics, University of Southampton SO17 1BJ, United Kingdom

Corresponding authors:  I.Tzouvadaki@soton.ac.uk and T.Prodromakis@soton.ac.uk 

Data collection period: 6/2019-2/2020

Dataset DOI: 10.5258/SOTON/D1439

Location: Southampton

Licence CC BY

Associated Publication: Tzouvadaki, I., Stathopoulos, S., Abbey, T., Michalas, L., & Prodromakis, T. (2020). Monitoring PSA levels as chemical state-variables in metal-oxide memristors. Scientific Reports.

Associated Projects: Royal Society IF160146, EU H2020 796366, EPSRC EP/R024642/1

Fig 1c-d
•	Description: Transient response of a memristor’s state-variable resistive states in response to the voltage input pulses.
•	Methods: The Resistive state (RS) of each device is monitored by means of a custom-made instrumentation and software (Arc Instruments [1]) allowing fully automated device-by-device measurements of entire packaged arrays. 
Fig 2c-d
•	Description: Transient response of a chemristor’s state-variable Resistive States  in response to d bio-chemical inputs rendering distinct Prostate Specific Antigen levels.
•	Methods: The Resistive state (RS) of each device is monitored by means of a custom-made instrumentation and software  (Arc Instruments [1]) allowing fully automated device-by-device measurements of entire packaged arrays. Namely, following the completion of each individual step and in order to extract the RS level of each case, the devices are subjected to non-switching pulses that allow the readout without affecting the state (0.2 V read pulses set at a 1 s sampling rate) for 1 min. 
Fig 3a
Description: Six identical devices (D1-6) are electroformed for bringing them in to two baseline operating regimes D1-3 (I) and D4-6 (II) in dry-condition.
   •	Methods: The electro forming process was performed as described in [1]
Fig 3b
•	Description: Six identical devices (D1-6) are exposed to a prostate specific antigen (PSA) solution with a mild PSA concentration of 0.6 ng/mL, resulting into a further shift in the baseline operating regimes,
   •	Methods: The Resistive state (RS) of each device is monitored by means of a custom-made instrumentation and software  (Arc Instruments [1] )
Fig 3c
•	Description: Transient response of a chemristor’s state-variable Resistive States  in response to d bio-chemical inputs rendering distinct Prostate Specific Antigen levels, depicting the corresponding PSA state-dependent responses for transducers  (D1-3) under consideration. 
•	Methods: The prostate specific antigen (PSA) concentration is progressively increased (tenfold) in four stages and following incubation the resistive states of all sensors are recorded for all four antigen concentrations.
Fig 3d
•	Description: Transient response of a chemristor’s state-variable Resistive States  in response to d bio-chemical inputs rendering distinct Prostate Specific Antigen levels, depicting the corresponding PSA state-dependent responses for transducers  (D4-6) under consideration. 
•	Methods: The prostate specific antigen (PSA) concentration is progressively increased (tenfold) in four stages and following incubation the resistive states of all sensors are recorded for all four antigen concentrations.  
Fig 4a
•	Description: Nine identical devices (D1-D9) are electroformed for acquiring hysteretic properties. All devices are then functionalized with anti-prostate specific antigen antibodies and converted to memristor-based sensing elements. Treatment with charged biological substances results into a further shift in the operating regimes. The sensors are subjected to a device-level hardware calibration, each individual chemical memristor is subjected to an initialization process comprising input programming pulses and the process is repeated until reaching the desired Resistive states level for all the sensors under study. 
•	Methods: The electro forming process was performed as described in [1] . For the surface modification, the devices are treated with O2 plasma for 15 min and converted to prostate specific antigen (PSA) chemical memristors (chemristors) through a direct-adsorption surface biofunctionalization with Anti-PSA antibodies. The sensors are subjected to a device-level hardware calibration, each individual chemical memristor is subjected to an initialization process comprising input programming pulses and the process is repeated until reaching the desired Resistive states level for all the sensors under study. The initialisation process was performed as described in [1].
Fig 4b
•	Description: Resistive state levels achieved for the sensors (D1-D9) after the normalization procedure are represented via different pixel colors and intensities.
•	Methods: The sensors are subjected to a device-level hardware calibration, each individual chemical memristor is subjected to an initialization process comprising input programming pulses and the process is repeated until reaching the desired Resistive states level for all the sensors under study. The initialisation process was performed as described [1]. 
Fig 4c
•	Description: Corresponding PSA Resistive State level relative change (%)-dependent responses of the nine chemical memristors (D1- D9) after exposure to different PSA concentrations as illustrated by indexed color representation.
•	Methods: The normalized sensor platform is then employed as an antigen sensing array, by implementing custom-made instrumentation and software [1]. Groups of individual chemristors are exposed to three prostate specific antigen concentrations and their resistive state response is recorded, more specifically, D3, D4 and D9 to a concentration of 60.9 ng/mL, D1, D5 and D6 to 0.6 μg/mL and D2, D7 and D8 to 6.1 μg/mL and the resistive state levels relative percentage change with respect to an initial, mild analyte concentration, operating regime, is extracted, corresponding to the three employed PSA concentrations.

[1] Scientific Reports  volume 7, Article number: 17532 (2017)