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| DNA定量 |
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| 作者:Protocol 实验频道来源:本站原创 点击数: 更新时间:2004-7-21 |
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Characterization of dna
LEVEL I
Materials
- DNA sample
- SSC buffer
- UV spectrophotometer 3 and quartz cuvettes
Procedure
- Dissolve a small quantity of your extracted DNA in 3.0 ml of 0.1X SSC.
- Turn on and blank a UV spectrophotometer at 220 nm (use 0.1X SSC as the blank). Determine the absorbance of your sample DNA at 230 nm.
- Change the wavelength to 230 nm, reblank the spectrophotometer and measure the absorbance of the sample at 230 nm.
- Increment the wavelength by 10 nm and repeat blanking and measuring the absorbance until readings are taken through 300 nm.
- Compute the absorbance ratio 260 nm to 280 nm. Pure DNA (without protein or RNA) will have a 260:280 absorbance ratio of 1.85. RNA will have a 260:280 ratio of 2.0.
- Plot the absorbance spectrum of your sample and indicate the 260:280 ratio, as well as the amount of protein contamination on the graph.
Wavelength
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Absorbance
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220
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230
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240
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250
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260
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270
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280
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290
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300
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处理 SSI 文件时出错
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处理 SSI 文件时出错
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