Temperature and pH sensors based on graphenic materials.

Area of Science:

• Biomedical Engineering
• Materials Science
• Sensor Technology

Background:

• Continuous patient monitoring outside clinical settings requires advanced, wearable sensors.
• Disposable and durable sensors are crucial for improved therapies and patient quality of life.
• Graphene-based materials offer unique properties for developing novel biosensors.

Purpose of the Study:

• To fabricate and evaluate the performance of wearable temperature and pH sensors for healthcare applications.
• To assess the accuracy, sensitivity, and durability of the developed sensors.
• To confirm the biocompatibility of the sensors for biological use.

Main Methods:

• Fabrication of temperature sensors using reduced graphene oxide (rGO) and pH sensors using graphene oxide (GO) on a biocompatible board.
• Testing sensor performance in human serum samples across relevant temperature (25-43°C) and pH (4-10) ranges.
• Evaluating sensor accuracy against reference instruments and assessing long-term stability (one week) and in vitro cytotoxicity with human fibroblast cells (MRC-5).

Main Results:

• The rGO temperature sensor demonstrated a sensitivity of 110±10Ω/°C with an error of 0.4±0.1°C.
• The GO pH sensor exhibited a sensitivity of 40±4mV/pH and a maximum deviation of 0.2pH units over one week.
• In vitro cytotoxicity tests confirmed the sensors' biocompatibility with MRC-5 cells over 24 hours.

Conclusions:

• Wearable graphene-based temperature and pH sensors have been successfully fabricated and demonstrated.
• The sensors exhibit high sensitivity, accuracy, and stability, suitable for real-time patient monitoring.
• These biocompatible sensors hold significant potential for point-of-care diagnostics and personalized healthcare.