Analysis of DNA or RNA

To measure the DNA content you can use a UV spectrophotometer with the benefits are not destructive and allows samples to be returned for further analysis or manipulation Spectrophotometer using the fact that there is a correlation between the absorption of ultraviolet light by DNA / RNA and its concentration in the sample In particular this post I will give you the facts about the relationship between DNA / RNA in the test wavelength spectrophotometer

1 The maximum absorption of DNA / RNA is about 260 nm This figure is the average absorption of the individual nucleotides that vary between 256 and 281 nm

2 In the case of RNA the concentration of a sample containing RNA may be calculated following equation:

40 x OD260 of sample = concentration of RNA (micrograms / mol)
And the equation for the concentration of DNA:

50 x OD260 = concentration of sample DNA (micrograms / mol)

Equations that describe the time-OD 260 is a concentration of RNA samples will be approximately 40 micrograms / ml (50 micrograms / ml for DNA)

3 We can also evaluate the degree of purity of nucleic acids by examining the absorption of other wavelengths where the protein and polysaccharide know the absorption maxima Proteins known to absorb strongly at 280 nm and polysaccharides can be identified with a maximum of up to 230 nm

4 Therefore in assessing the level of purity of nucleic acids using the relationship between measurements of the three wavelengths of 230 nm 260 nm and 280 nm

5 For example a sample containing only the following RNA extraction methods are not considered contaminated if the ratio is 1: 2: 1 and DNA is 1: 18: 1 (OD-230 reflects: 260: 280 ratio) If there are no significant deviations from the relationship then it is clear that the contaminants are present and further purification of the required samples
In many cases the purity and concentration can be further obscured by the presence of reagents used in the extraction process itself Some features are obvious in the scanning spectrophotometer which includes three wavelengths indicated Therefore when using spectrometry in the analysis of DNA or RNA you should be aware of potential problems that could produce a misleading report Also if the analysis reports and the concentration of DNA or RNA spectrophotometer are also necessary not only to obtain readings at 280 260 and 230 nm but also to analyze the whole range 200-320 nm Impressions reagents used in the extraction process can influence and provide misleading information that could influence the next manipulation