An innovative concept of a low-cost pH optode with working volumes of less than 150 mu L is presented. The pH monitoring is based on the color changing effect of pH indicators. The optode includes an RGB color sensor patch TCS34725 from Adafruit, a controllable LED and reactor slides and is addressed by a self-written LabVIEW ((C)) software. Utilizing the hue value of the HSV color model, it is possible to analyze the color change of the indicator and estimate the pH value of the analyzed samples by exploiting sigmoidal fit models. Measurements carried out with phenol red and DMEM (Dulbecco's Modified Eagle's Medium) reported a standard error of calibration in the physiologic pH range (6.5-7.5) of +/- 0.04 pH units.
Rogge, C., Zinn, S., Prosposito, P., Francini, R., Foitzik, A.h. (2017). Transmitted light pH optode for small sample volumes. JOURNAL OF SENSORS AND SENSOR SYSTEMS, 6(2), 351-359 [10.5194/jsss-6-351-2017].
Transmitted light pH optode for small sample volumes
Rogge C.;Prosposito P.;Francini R.;
2017-01-01
Abstract
An innovative concept of a low-cost pH optode with working volumes of less than 150 mu L is presented. The pH monitoring is based on the color changing effect of pH indicators. The optode includes an RGB color sensor patch TCS34725 from Adafruit, a controllable LED and reactor slides and is addressed by a self-written LabVIEW ((C)) software. Utilizing the hue value of the HSV color model, it is possible to analyze the color change of the indicator and estimate the pH value of the analyzed samples by exploiting sigmoidal fit models. Measurements carried out with phenol red and DMEM (Dulbecco's Modified Eagle's Medium) reported a standard error of calibration in the physiologic pH range (6.5-7.5) of +/- 0.04 pH units.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
