Table 2.

Absorbance control values of the samples at 1 cm pathlength measured using a high accuracy dual beam spectrophometer at 22°C and 0.8 nm spectral bandwidth. The values in the parentheses are CV (%) of the mean from N = 9 (genomic DNA) and N = 4 (oligoncleotide samples), except for the *SRM 2082 components that are the standard uncertainties calculated as described in the NIST certificate of analysis (https://www.nist.gov/srm) calcuated using extensive measurements.

Test sample	Abs. 260 nm	Abs. 280 nm	Ratio 260 nm/280 nm
Human genomic DNA	1.029 (5.0%, N = 9)	0.553 (6.5%, N = 9)	1.85
Oligonucleotide low	6.247 (0.2%, N = 4)	3.755 (0.1%, N = 4)	1.66
Oligonucleotide high	24.943 (0.1%, N = 4)	14.972 (0.1%, N = 4)	1.67
SRM 2082 Uracil	7.990 (0.003)*
SRM 2082 Tryptophan		8.350 (0.003)*