Near-Infrared Measurement Standard Artifact
It is important that a spectrophotometer is qualified in a metrological manner to demonstrate that it is “fit for its intended purpose” prior to running any critical analytical method on it. Demonstration that an absorption spectrophotometer is “fit for its intended purpose” means that all relevant spectrophotometer parameters be tested and that the accuracy of each qualification measurement result meets or exceeds the specifications set forth in the analytical instrument requirements section of the validation protocol for each analytical method. For analytical methods run in the 650 nm to 900 nm wavelength region, the reference material artifacts must be certified so that their measurement scopes of calibration are applicable to this spectral region.
To continue with its history of innovation in UV/VIS spectrophotometric metrology, Stranaska Scientific is pleased to announce the availability of CRM 1405 for science-based testing of absorption spectrophotometers that are used in the short-wave, near infrared (SW-NIR) region of the spectrum. The Refmacal CRM 1404 spectrophotometer calibration kit is comprised of glass filters that enable the testing of the following three important instrumental parameters:
- Spectral Bandwidth (Resolution)
- Wavelength Accuracy
- Photometric Accuracy/Linearity
Spectral bandwidth, or resolution, is tested by comparing measured absorbance ratios of two absorption bands in the 740 nm to 749 nm wavelength region to the certified reference absorption ratios provided in the Certificate of Calibration. The accuracy of the wavelength scale is tested by comparing the measured locations of minimum transmittance (or maximum absorbance) of five narrow absorption bands having nominal wavelength locations at 685 nm, 740 nm, 748 nm, 807 nm and 880 nm to the certified reference wavelengths provided in the Certificate of Calibration. The accuracy and linearity of the photometric scale is tested by comparing the measured values in transmittance or transmittance density (absorbance) of each of four photometric glass filters at wavelengths 650. nm, 700 nm, 750 nm, 800 nm and 880 nm the certified reference values provided in the Certificate of Calibration. The four glass filters have nominal percent transmittances of 1%T, 3%T, 10%T and 30%T which correspond to transmittance densities (absorbances) of 2.0, 1,5, 1.0 and 0.5, respectively.
