UV-vis Spectroscopy

The development of a method for the simultaneous determination of glycine, triglycine and fructose using UV–vis and evaporative light-scattering detection (ELSD) is described. This was necessary as part of a research project dealing with the recovery of functional peptides from aqueous streams on an industrial scale using adsorption or related technologies. Fructose is barely detectable by UV–vis as it lacks detectable functionalities, while glycine and triglycine are both UV–vis sensitive. An NH2 phase was chosen as a column and separation was obtained within seven minutes on a 250 X 4.6 mm column. Limits of detection are approximately 40 mg fructose/L, 4 mg glycine/L and 0.05 mg triglycine/L. Calibration functions are linear in a range of 40–1400 mg/L for fructose, 5–200 mg/L for glycine and 0.5–70 mg/L for triglycine.

In an upcoming spacewalk, shuttle astronauts will swap the Corrective Optics Space Telescope Axial Replacement (COSTAR) device for the new Cosmic Origins Spectrograph (COS).

Some powders and rough surfaced solids change color as a function of temperature, a phenomenon known as thermochromism. Such phenomena can be effectively studied by UV-Visible spectroscopy in combination with a diffuse reflection accessory equipped with temperature-controlled reaction chamber, as demonstrated here with a thermal paint.

Data are presented for a pH-adjustable liquid UV-matrix-assisted laser desorption ionization (MALDI) matrix for mass spectrometry analysis. The liquid matrix system possesses high analytical sensitivity within the same order of magnitude as that achievable by the commonly used solid UV-MALDI matrices but with improved spot homogeneity and reproducibility. The pH of the matrix has been adjusted, achieving an on-target pH range of 3.5?8.6, which has allowed for the performance of a tryptic digest within the diluted pH-optimized liquid matrix.

While the overall laboratory UV and Visible spectroscopy market was worth well over $700 million in 2007, the UV/Vis/NIR segment represented less than 10% of it. UV/Vis/NIR instruments utilize multiple detectors to cover a broader spectrum of analysis, and typically are among the highest-end systems in the UV-Vis market.

Data are presented for a pH-adjustable liquid UV-matrix-assisted laser desorption ionization (MALDI) matrix for mass spectrometry analysis. The liquid matrix system possesses high analytical sensitivity within the same order of magnitude as that achievable by the commonly used solid UV-MALDI matrices but with improved spot homogeneity and reproducibility. The pH of the matrix has been adjusted, achieving an on-target pH range of 3.5?8.6, which has allowed for the performance of a tryptic digest within the diluted pH-optimized liquid matrix.