Anal. Chem. 1980, 52, 321-325
attempting to determine equivalent weights for plasma polymer to probe this question.
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321
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RECEIVED for review June 20, 1979. Accepted November 26, 1979. This research was supported in part by grants from the Office of Naval Research and National Science Foundation. R.J.N. acknowledges support of the National Research Council in preparation of the manuscript; F.A.S. acknowledges sabbatical leave from Florida Atlantic IJniversity. This is Part XX of a series on Chemically Modified Electrodes. Presented in part at the 177th National Meeting of the American Chemical Society, Analytical Division, Honolulu, Hawaii, March 1979.
Determination of Low Molecular Weight Volatile Fatty Acids in Aqueous Samples Michael J. Barcelona,*' Howard M. Liljestrand,* and James J. Morgan W. M. Keck Laboratories of Environmental Engineering Science, California Institute of Technology, 138-78,Pasadena, California 9 1 125
An lonexchange/derivatlzation procedure is described for the determination of C,-Cs volatile fatty acids in a range of dinicuk aqueous matrices. The resulting p-bromophenacyi esters may be separated via either HPLC or GLC techniques depending on desired selectlvity and sensitivity. Micromolar concentrations of these acids can be determined to better than f0.20 pM within 95% confidence intervals. Sewage and marine sediment pore water analyses can be performed on small samples (
