Monitoring and measurement of carbon dioxide is critical for many fields, however the gold standard CO2 sensor, the Severinghaus electrode, has remained unchanged for decades. In recent years, many dye-based CO2 sensors have been demonstrated. However, fabrication of these optochemical CO2 sensors require complex chemistry steps and are difficult to control and repeatably execute. Here, we report a facile CO2 sensor fabrication method for continuous monitoring that does not suffer from the issues mentioned above. This method utilizes polydimethylsiloxane (PDMS) as the sensor matrix, and 1-hydroxypyrene-3,6,8-trisulfonate (HPTS), a pH sensitive dye, as the sensing material. HPTS, base (NaOH), and glyercol are loaded and cured into a thin PDMS layer by using the density-induced droplet precipitation (DIDP) method. The fabrication process is fast and does not require prior knowledge in chemistry or device fabrication. We demonstrate the application of this sensor for in-line CO2 quantification in cell culture media. To this end, we optimized the sensing composition to quantify CO2 in the range of 0 to 20kPa. A standard curve was generated with high fidelity (R2 = 0.995) along with high analytical resolution of under 0.4kPa. Additionally, the sensor is fully autoclavable with a working lifetime of &gt;1 month. This flexible, simple to manufacture sensor has a myriad of potential applications ranging from continuous biomanufacturing to wearable personal health monitoring, and represents a new, straightforward means for optical carbon dioxide measurement.

Next-generation carbon dioxide measurement: flexible sensor patch for continuous monitoring

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.