Rapid Comparison of UVB Absorption Effectiveness of Various Sunscreens by UV-Vis Spectroscopy

UV-Vis spectroscopy of stardust

NASA’s Stardust mission flew through the coma of comet Wild 2 in January 2004, capturing dust grains as it did so. The grains were returned safely to Earth in January 2006, and are in the process of being distributed to investigators. As members of the Spectroscopy Preliminary Examination Team, we are preparing to analyse Stardust grains. Our contribution is to measure the spectrum of the grain...

SUSPENSION STABILITY OF TITANIA NANOPARTICLES STUDIED BY UV-VIS SPECTROSCOPY METHOD

Ultraviolet–Visible (UV–Vis) spectroscopy was used, in the current investigation, to explore the dispersion and stability of titania nanoparticles in an aqueous media with different types of dispersants. Hydrochloric and nitric acids as well as ammonia were used to determine the stability of the suspension in the acidic region (pH=2.5) and basic area (pH=9.5), respectively. In addition, for mea...

Analysis of poly(amidoamine) dendrimer structure by UV-vis spectroscopy.

We report a UV-vis spectroscopic study of four different types of poly(amidoamine) dendrimers. The results indicate that the degree of protonation of the interior tertiary amines of these dendrimers correlates directly to an absorption band with λ(max) in the range of 280-285 nm. Specifically, at low pH, the tertiary amines are protonated and the 280-285 nm band is absent. However, at elevated ...

Chlorophylls and Carotenoids: Measurement and Characterization by UV-VIS Spectroscopy

The quantitative determination of chlorophyll (Chl) a, Chl b, and carotenoids in a wholepigment extract of green plant tissue by UVVIS spectroscopy is complicated by the choice of sample, solvent system, and spectrophotometer used. The various plant pigments absorb light in overlapping spectral regions, depending on the system selected. This unit discusses methods used to account for such overl...

Significance of UV-Vis spectroscopy in in vitro release studies