Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

On-line pH detection of cell culture environment is necessary in a bioprocess or tissue engineering. Devices by means of electrochemical mechanisms for this purpose have been reported to be less suitable compared with optical-based sensing principles. More recently, some non-invasive optical sensing systems have been proposed for online pH monitoring of cell culture environment. However, these devices are not for multi-target pH monitoring purpose, and are large in scale and thus not appropriate for the pH monitoring at a micro scale such as in microbioreactor or microfluidic-based cell culture platform. To tackle these issues, an optical fiber sensor array for on-line pH monitoring was proposed using microfluidic technology. The working principle is based on the optical absorption of phenol red normally contained in culture medium. Different from other device of the similar working principle, the proposed device requires less liquid volume (less than 0.8 microl), is non-invasive, and particularly can be configured as an array for high throughput pH monitoring. The present device has been optimized for the shape of detection chamber in a microfluidic chip with the aid of computational fluid dynamics (CFD) simulation, to avoid flow dead zone and thus to reduce the response time of detection. Both simulation and experimental results revealed that the design of oval detection chamber (axis, 1.5 and 2.0 mm) can considerably reduce the response time. Preliminary test has proved that the optical pH detection device is able to detect pH with average detection sensitivity of 0.83 V/pH in the pH range of 6.8-7.8, which is normally experienced in mammalian cell culture.

Original publication

DOI

10.1007/s10544-008-9233-0

Type

Journal article

Journal

Biomed Microdevices

Publication Date

02/2009

Volume

11

Pages

265 - 273

Keywords

Animals, Cell Culture Techniques, Computer Simulation, Electrochemical Techniques, Humans, Hydrogen-Ion Concentration, Microfluidic Analytical Techniques, Optics and Photonics, Sensitivity and Specificity