A new Certified Reference Material from Starna Scientific allows the ultimate sensitivity of high-performance spectrofluorometers to be estimated. Traditionally, this was tested using very dilute solutions of fluorophores such as Quinine Sulfate. Near the detection limit, however, concentrations are so low that sample preparation becomes difficult, and there is a real risk of contamination.
When excited by UV or visible radiation, water emits a Raman peak that can be readily identified. Because very few photons are involved in Raman scattering, the signal levels are very low, comparable to those produced by very low analyte concentrations in normal fluorescence measurements. The intensity and signal-to-noise ratio of the Raman signal therefore indicate the ultimate detection limit of the spectrofluorometer.
The reference material is a permanently sealed UV quartz 10mm fluorometer cuvette containing ultra-high purity water, supplied with a Certificate of Validation and full instructions for use. The certificate shows typical Raman spectra measured on a reference spectrophotometer traceable to NIST primary references, and signal-to-noise ratios calculated at two different excitation wavelengths.
Starna Scientific is accredited to ISO Guide 34 and ISO 17025. Subject to appropriate storage and use, all Starna Certified Reference Materials carry a lifetime guarantee.Starna Scientific Ltd.