Nucleic acid quantification, as one of the most fundamental experiments in molecular biology, directly affects the outcome of downstream experiments. The accuracy of nucleic acid quantification is crucial. At present, there are two main methods of NGS library quantification, the ultraviolet absorption method, and the fluorescent dye method.

The ultraviolet absorption method uses a spectrophotometer to measure the absorbance at 260 nm for DNA and RNA to quantification. It also estimates the purity of nucleic acids by calculating the OD260/OD280 ratio. However, the detected values are highly susceptible to interference from other contaminants such as free nucleotides, salts, and organic compounds.

Qubit fluorometric quantitation utilizes fluorescent dyes that specifically bind to double-stranded DNA, single-stranded DNA, RNA, or proteins. Upon excitation by a specific wavelength light source, the dyes emit fluorescence, which is not affected by other impurity molecules that may be present in the sample. The fluorescence intensity is proportional to the concentration of the target molecules in the sample.

Table 1. Comparison of Mainstream Nucleic Acid Quantification Methods

UV absorbance and Qubit fluorometric quantitation each have their advantages and can complement each other. For preliminary quantification of routine nucleic acid samples to determine concentration, purity, and the presence of contaminants, absorbance quantification method can be chosen. Qubit quantification is more suitable for low-concentration precious samples or precise quantification required for downstream experiments, such as next-generation sequencing and real-time quantitative PCR.

Yeasen has launched several Qubit quantification products: dsDNA HS Assay Kit for Qubit^® (Cat#12640), Ready to use: 1× dsDNA HS Assay Kit for Qubit^® (Cat#12642), ssDNA Assay Kit for Qubit^® (Cat#12645), and dsDNA BR Assay Kit (Cat#12643), which have been widely praised since their launch.

Solution 1 dsDNA HS High Sensitivity Quantification

Ready-to-use dsDNA quantification premix—1× dsDNA HS Assay Kit for Qubit^®

^{Easy operation: Ready-to-use premix, no need for pre-mixing;}

^{High sensitivity: Detectable concentration as low as 50 pg/μL;}

^{Good stability: Fluorescence signal lasts for 3 hours, and room temperature storage for 20 days does not affect the accuracy of quantification;}

^{A.Superb stability: Room temperature storage for 2 weeks still maintains stability (the measured value deviates from the theoretical value by less than 10%).} 

Table 2. Stability Test of Different Samples at 4°C and Room Temperature Compared to Competitors

B.High sensitivity, good batch-to-batch stability

Table 3. Stability Test of Different Batches

Solution 2 dsDNA BR Broad Range Quantification

Broad range dsDNA quantification—dsDNA BR Assay Kit

High sensitivity: Detectable concentration as low as 50 pg/μL;

Excellent linearity: Good linearity within the range of 2-1000 ng;

Strong tolerance to contaminants: Can tolerate common contaminants.

Table 4. Stability and Tolerance to Contaminants Compared to Competitors

Solution 3 ssDNA Quantification

The ideal choice for ssDNA quantification—High cost-performance ssDNA Assay Kit for Qubit^®

A.Good repeatability: Quantification in different Qubit instruments, different types of samples using Yeasen multiple batches of Cat#12645 tested. Within the range of 0-200ng, good repeatability in measurements from different Qubit instruments.