Concentration of Nucleic Acid
Accurate determination of nucleic acid concentration and yield is essential for various applications, such as evaluating the efficacy and optimizing dosages of nucleic acid drugs. This importance arises from the necessity for precise quantification to ensure the validity and reproducibility of experimental outcomes. Creative Biolabs offers a range of methods for nucleic acid concentration determination, as shown in Tab.1.
Tab.1 Methods for testing nucleic acid concentrations.
| Methods | Description |
|---|---|
| UV absorbance (optical density) |
UV spectrophotometry is the primary method for quantifying nucleic acids. In this method, the sample is placed in a quartz cuvette inside a UV spectrophotometer, and UV light passing through the sample measures absorbance at specific wavelengths. The peak absorbance of nucleic acids (DNA or RNA) at 260 nm is attributed to the presence of conjugated double bonds within their purine and pyrimidine structures. The Beer-Lambert equation, A = εcl, is used to calculate concentration, where A is UV absorbance, ε is the extinction coefficient, c is the nucleic acid concentration, and l is the light path length. For shorter nucleic acid molecules, extinction coefficients are calculated based on the sequence. |
| Fluorometric methods |
Fluorometric techniques are highly sensitive methods for nucleic acid quantitation. These methods utilize fluorescent dyes that intercalate into nucleic acid grooves, bind DNA or RNA non-specifically, or selectively target nucleic material. Variations in the spectral properties of fluorophores bound to nucleic acids enable the determination of sample concentrations. |
| Gel electrophoresis |
Gel electrophoresis separates DNA and RNA from impurities based on their size and shape. During agarose gel electrophoresis, the DNA or RNA sample is loaded into a well within the gel matrix, after which it undergoes electrophoresis under the influence of an electric field. The negatively charged nucleic acid migrates toward the anode. Nucleic acid concentration and yield can be determined by comparing the intensity of sample bands to standards with known amounts. |
| Quantitative PCR (qPCR) | qPCR employs either fluorometric probes or fluorescent dyes to monitor the amplification process. The fluorescence intensity correlates with the total amount of DNA present. Utilizing a standard curve allows for the determination of target DNA quantities in test samples. |
| Digital PCR (dPCR) | dPCR provides increased sensitivity in detecting rare targets or subtle changes in target concentration, serving as an alternative method for quantifying DNA that eliminates the necessity for a standard curve. |
SERVICES
Creative Biolabs is dedicated to providing nucleic acid concentration services for customers worldwide. With advanced technology and skilled scientists, our service is reliable. For detailed information, please contact us to request a quote. We guarantee a response within 24 hours and will collaborate with you to tailor the optimal method for your project.
