title: Combined imaging and chemical sensing of fertilization-induced acid release from single sea urchin eggs.
abstract: We demonstrate a microarray sensor capable of obtaining both chemical and visual information on multiple cells simultaneously with single-cell resolution. The array was fabricated by covalently immobilizing a thin, pH-sensitive polymer layer on the distal end of an optical imaging fiber. The sensor's ability to measure localized chemical dynamics in real-time was evaluated using sea urchin fertilization biochemistry as a model system. Following sea urchin fertilization, the Na(+)/H(+) transporter is activated to exchange extracellular sodium ions for intracellular hydrogen ions, causing a release of hydrogen ions at the egg's surface. By placing the pH sensor proximal to the egg and switching between a fluorescence image and a white light image, we were able to observe both localized pH changes following fertilization as well as morphological transformations during cell division.
authors.affiliation: Department of Chemistry, Tufts University, Medford, Massachusetts 02155, USA.
authors.forename: K L
authors.initials: KL
authors.lastname: Michael
authors.forename: D R
authors.initials: DR
authors.lastname: Walt
mesh_terms: D000818:Animals; D002455:Cell Division; D005260:Female; D005306:Fertilization / Q000502:physiology*; D005336:Fiber Optic Technology / Q000295:instrumentation*; D006863:Hydrogen-Ion Concentration; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation; D008027:Light; D008297:Male; D008853:Microscopy / Q000295:instrumentation; D008856:Microscopy, Fluorescence / Q000295:instrumentation; D010063:Ovum / Q000502:physiology*; D012617:Sea Urchins / Q000502:physiology*; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism
chemical_list: D017923:Sodium-Hydrogen Exchangers