Surface-enhanced Raman assays (SERA): measurement of bilirubin and salicylate

Results of a study to detect bilirubin and salicylate using SERS and a reactive coating are presented. The motivation for this work was to devel to develop an assay that would simplify an analysis by detecting the analyte in a whole blood sample. This would remove the risks and time associated with preparing a serum sample. Quantitative analysis was performed using partial least-squares. The results are that one can detect bilirubin and salicylate in whole blood at levels below the normal or therapeutic levels using a coating based on an argentiphilic diazonium molecule. The sharp Raman bands associated with the analyte–coating adduct are sufficiently resolved to allow the analyte to be detected in the presence of a complex matrix such as whole blood. Copyright © 1999 John Wiley & Sons, Ltd.