title: Ratiometric fluorescent pH-sensitive polymers for high-throughput monitoring of extracellular pH.
abstract: Extracellular pH has a strong effect on cell metabolism and growth. Precisely detecting extracellular pH with high throughput is critical for cell metabolism research and fermentation applications. In this research, a series of ratiometric fluorescent pH sensitive polymers are developed and the ps-pH-neutral is characterized as the best one for exculsive detection of extracellular pH. Poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) is used as the host polymer to increase the water solubility of the pH sensitive polymer without introducing cell toxicity. The fluorescent emission spectra from the polymeric sensor under excitation at the isosbestic point 455 nm possess two fluorescence peaks at 475 nm and 505 nm, which have different responding trends to pH. This enables the polymer to detect pH using fluorescent maxima at 475 nm and 505 nm (I475nm/I505nm) ratiometrically. The cell impermeability ensures the sensor can solely detect the environmental pH. The sensor is tested to detect the extracellular pH of bacteria or eukaryotic cells in high throughput assays using a microplate reader. Results showed that the pH sensor can be used for high throughput detection of extracellular pH with high repeatability and low photobleaching effect.
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Liqiang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Fengyu
authors.initials: F
authors.lastname: Su
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Xiangxing
authors.initials: X
authors.lastname: Kong
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Fred
authors.initials: F
authors.lastname: Lee
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Kevin
authors.initials: K
authors.lastname: Day
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Weimin
authors.initials: W
authors.lastname: Gao
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Mary E
authors.initials: ME
authors.lastname: Vecera
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Sohr
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Sean
authors.initials: S
authors.lastname: Buizer
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).|Department of Materials Science and Engineering, South University of Science and Technology of China, No. 1088, Xueyuan Rd., Xili, Nanshan District, Shenzhen, Guangdong, 518055 (China).
authors.forename: Yanqing
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Center for Biosignatures Discovery Automation, Biodesign Institute, Arizona State University, 1001 S. McAlister Ave., P.O. Box 876501, Tempe, AZ 85287 (USA).
authors.forename: Deirdre R
authors.initials: DR
authors.lastname: Meldrum