Hasil untuk "physics.space-ph"

M. Kühl, Y. Cohen, T. Dalsgaard et al.

W. Wilfinger, Karol Mackey, P. Chomczyński

The ratio of absorbance at 260 and 280 nm (the A260/280 ratio) is frequently used to assess the purity of RNA and DNA preparations. Data presented in this report demonstrate significant variability in the RNA A260/280 ratio when different sources of water were used to perform the spectrophotometric determinations. Adjusting the pH of water used for spectrophotometric analysis from approximately 5.4 to a slightly alkaline pH of 7.5-8.5 significantly increased RNA A260/280 ratios from approximately 1.5 to 2.0. Our studies revealed that changes in both the pH and ionic strength of the spectrophotometric solution influenced the A260/280 ratios. In addition, the ability to detect protein contamination was significantly improved when RNA was spectrophotometrically analyzed in an alkaline solution. UV spectral scans showed that the 260-nm RNA absorbance maximum observed in water was shifted by 2 nm to a lower wavelength when determinations were carried out in Na2HPO4 buffer at a pH of 8.5. We found RNA A260/280 ratios to be more reliable and reproducible when these spectrophotometric measurements were performed at pH 8.0-8.5 in 1-3 mM Na2HPO4 buffer.

Kangtaek Lee, S. Asher

Mingchun Zhao, M. Liu, G. Song et al.

A. Park, L. Fan

A. Pol, K. Heijmans, H. Harhangi et al.

D. Bhumkar, V. Pokharkar

M. Kosmulski

AbstractNo abstract is available for this article.

M. Peñalva, J. Tilburn, E. Bignell et al.

AbstractNo abstract is available for this article.

AbstractNo abstract is available for this article.

No abstract is available for this article.

M. Gilar, Petra Olivova, Amy E Daly et al.

Mubarak Ali, P. Ramirez, S. Mafe et al.

S. Roche, S. Bressanelli, F. Rey et al.

AbstractNo abstract is available for this article.

AbstractNo abstract is available for this article.

AbstractNo abstract is available for this article.

AbstractNo abstract is available for this article.