Using Inductively Coupled Plasma Atomic Emission Spectroscopy to investigate the mineral content in several commercial vitamin tablets.   Several brands of vitamin tablets are being analyzed for the elements:  Ca, Cu, Cr, Fe, K, Mg, Mn, Mo, Ni, Ti, V and Zn.  A comparison of the efficiency for three different sample digestion techniques are also under investigation:  microwave digestion, digestion by dri-block heater and muffle furnace.   Department of Chemistry, Oregon State University, Corvallis, Oregon 97331.  Contact Dr. Christine Pastorek,

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After a trip to Chemistry Stores for Argon, setting up the Ar cylinder is the next step-what fun!

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The Ar gas regulator is carefully installed and set to 90 psi.

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The peristaltic pump is readied so that the sample can be pumped into the spray chamber.

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The analysis method is composed on the computer. A typical method consists of the known analysis wavelength for each element, the known standard concentrations and the signal integration time for each measurement.

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The digested vitamin samples are filtered before analyzing to avoid clogging the fine bore nebulizer that produces a mist of sample solution. 

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The misted sample solution then goes into the hot argon plasma (7000K) where the metal atoms are electronically excited and subsequently emit light at characteristic wavelengths.  The intensity of the emitted light is measured by the photomultiplier (PMT) detector.  The light intensity is proportional to the concentration of the metal in the sample.