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Modernizing Trace Organic Analysis.
pop over to these guys The purpose of organic trace analysis is to obtain information about the organic molecules present in the sample matrix of interest.
So why is organic trace analysis so hard?
There are millions of organic compounds that have been characterized in the chemical literature, with still millions more that are waiting to be discovered. The biggest problem with organic trace analysis is isolating the single compound of interest from the rest of the organic soup.
Analytical instrumentation has evolved to the point where is capable of simultaneously detecting the hexane molecule, and all of the other C6H14, compounds in a matter of minutes at levels less than one part per billion (ppb).
Despite the sophisticated arsenal of analytical instrumental techniques available, current instrumentation has not evolved to the point where we put some dirt into a chamber and the answer appears. Samples must still undergo some type of pretreatment because the sample matrices often are not compatible with the modern instrumentation. In addition, the sample homogeneity must be reduced to a molecular level because today’s analytical instruments compare molecular relationships on a molecular level with time integration.
This additional pretreatment component for modern analysis makes the determination of trace organic analytes challenging for analytical chemists.
The various operations performed on the sample during its preparation for instrumental analysis account for 60% of the analyst’s time and are responsible for 30 to 50% of error in performing the analysis.
The top problems reported with sample preparation are: 1) labor intensity; 2) cost; 3) poor recoveries; 4) reproducibility; and 5) contamination. In addition to these problems the trace organic chemists on average uses three or more sample preparation techniques per sample just to produce an analytical result.
try this This book focuses on helping today’s trace organic analysists understand and overcome the difficulties of sample preparation by learning how to THINK GREEN.