Journal
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
Volume 398, Issue 5, Pages 1883-1889Publisher
SPRINGER HEIDELBERG
DOI: 10.1007/s00216-010-4130-9
Keywords
Fluorescence; pH; HPTS; Exudate; V-taper sensing probe
Funding
- Ministry of Education, Youth and Sport of the Czech Republic [LC06034]
- Grant Agency AS CR [IAA600380805]
- National Science Foundation [102/08/P639]
Ask authors/readers for more resources
Determining the pH values of microscopic plant samples may help to explain complex processes in plants, so it is an area of interest to botanists. Fiber-optic probes with small dimensions can be used for this purpose. This paper deals with the fiber-optic detection of the pH values of droplets of plant xylem exudate based on ratiometric fluorescence intensity measurements with an internal reference. For this purpose, novel V-taper sensing probes with a minimum diameter of around 8 mu m were prepared that enable the delivery of fluorescence signal from the detection site on the taper tip to the detector. The taper tips were coated with pH-sensitive transducer (8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt; HPTS) and a reference [dichlorotris-(1,10-phenanthroline) ruthenium (II) hydrate (Ru-phen dichloride)] immobilized in a xerogel layer of propyltriethoxysilane and (3-glycidoxy)propyl trimethoxysilane. The prepared probes were sensitive to pH values mainly in the range from 6.0 to 9.0. In the pH range 6-9, the results were limited by measurement errors of about 0.2 pH units, and in the pH range 5-6 by measurement errors of about 0.5 pH units. Using the developed V-taper sensing probes, the pH values of in vivo and in vitro samples of small volumes (similar to 6 mu l) of exudate were measured. The results were validated by comparison with conventional electrochemical pH measurements.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available