Dr. Barbara M. Hopkins, Associate Professor
103A Logan Hall, (513)-745-2063
Two techniques available to the analytical chemist are High Performance Liquid Chromatography (HPLC) and inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). The former allows for separation of the components of a mixture and the latter is widely used for the analysis of metals. Coupling of the two techniques to form a hyphenated method, HPLC-ICP, enables the chemist to maximize the advantages of each. By the coupling process, the ICP instrument acts as the detector for compounds being separated by the HPLC. Two types of analysis that can be performed are elemental speciation and separation and detection of organometallic compounds that contain the same metal ion. Both types of analysis can be applied to measurements of compounds that are potential hazards to humans.
A series of compounds that lend themselves to analysis by HPLC-ICP are organotin compounds. Such compounds have the general formula R(n)SnX(4-n) in which R is an organic group, n ranges from 1 to 4, and X is an anion. Depending on the number of R groups the compounds are classified as mono-, di-, tri-, and tetra organotins. The degree of toxicity varies among the compounds. The trisubstituted compounds in general are the most toxic followed be the di- and monoorganotins. These compounds have many practical applications that include being used as pesticides, fungicides, catalysts and stabilizers for polymers.
An HPLC-ICP method for the qualitative and quantitative analysis of triphenyltin chloride has previously been developed at the National Institute for Occupational Safety and Health (NIOSH). This project will extend this analysis to other organotin compounds. For these compounds the chromatography conditions, the ICP conditions, and linearity studies to obtain the limits of detection (LOD) must be determined. Once these are known, a method for collecting these compounds in the workplace must be validated. This will include determination of filters to be used for collection followed by storage and recovery studies using the filters.
A student working on this project will learn how to use an ICP instrument for analysis of both inorganic and organic compounds. The project will also enable the student to become familiar with standard operating procedures used in an analytical laboratory for the development of a method that will become part of the NIOSH Manual of Analytical Methods.