DEVELOPING A RAMAN SPECTRAL METHOD FOR MEASURING THE STRONTIUM AND CALCIUM CONCENTRATIONS OF FISH OTOLITHS

Surface-enhanced Raman scattering (SERS) spectra of Ca2+ and Sr2+ comp lexes of four dyes (O-cresolphthalein, PAN black, murexide, and erioch rome-black T(EBT) are reported. It has been demonstrated that SERS spe ctra of the murexide complex of Ca2+ can be used for the accurate dete rmination of the cation in solutions at pH 12-8. Similarly, the SERS s pectra of the EBT complex of Sr2+ can yield accurate determination of the cation concentration in solutions at pH 12-8. The SERS technique h as linear resolutions of Sr2+ and Ca2+ concentrations down to 219 and 20 ppb, respectively. The chemistry of the otoliths of Hyperoglyphe an tarctica (Centrolophidae: Teleostei) and Beryx splendens (Berycidae: T eleostei) proved to be similar. Using the SERS murexide complex techni que for Ca and the SERS EBT complex for Sr, concentrations were 39.33% weight Ca and 272.7 ppm Sr for H. antarctica and 44.93% weight Ca and 273.133 ppm Sr for B. splendens.