resDetect™ CHO resDNA Quantitation Kit (qPCR)

Typical Data 

Please refer to DS document for the assay protocol.

Standard Curve
Prepare a 10-fold serial dilution of CHO DNA Control to generate standard curve samples SD1- SD6. Perform qPCR using the resDetect™ CHO resDNA Quantitation Kit (qPCR). The resulting standard curve should meet the following criteria: Amplification efficiency: 90-110%; Correlation coefficient (R2): 0.98; Slope: -3.10 to -3.58; Linear range: 300 pg/μL to 3 fg/μL.

Repeatability
Samples with concentrations of 3 pg/μL and 30 fg/μL were measured in 10 replicates. The acceptance criterion for the coefficient of variation (CV) in concentration was ＜20%. The CV of detected concentrations was under 5%, demonstrating that the assay provides highly reproducible and reliable quantitation of CHO residual DNA.

Lot-to-Lot Consistency Assessment
Three different lots of the resDetect™ kit were used to extract and quantify CHO DNA from samples with two different spiking levels. The acceptance criterion for recovery was 50–150%. The recovery rates for the three different reagent lots ranged from 95.27% to 104.36%, demonstrating consistent performance across different lots.

Specificity Assessment
Each well of the quantitative reference standards (SD1–SD6) was spiked with 6 pg of HEK293 DNA or 6 pg of E. coli DNA. The resulting standard curves were not affected by the presence of HEK293 or E. coli DNA, demonstrating that the resDetect™ CHO resDNA Quantitation Kit does not cross-react with unrelated DNA.

Compatibility with a Broad Range of DNA Fragment Sizes
CHO genomic DNA was fragmented by enzymatic digestion for 10, 20, and 30 minutes, generating DNA of varying fragment sizes. Each fragmented DNA sample was subjected to 10-fold serial dilution and quantified using qPCR. The resulting standard curves for all fragment sizes met acceptance criteria, indicating that DNA fragmentation has no significant impact on the assay performance.

Matrix Interference Assessment
The resDetect™ CHO resDNA Quantitation Kit was evaluated using samples in high-protein matrix (up to 150 mg/mL BSA) and in buffers with varying pH (pH 3.0–10.0). CHO DNA was spiked into these matrices, extracted, and quantified using the resDetect™ kits. The recovery acceptance criterion was 50–150%. The observed recoveries for all matrix types ranged from 98% to 120%, demonstrating that the assay performs reliably across different sample matrices.

The resDetect™ CHO resDNA Quantitation Kit was evaluated using samples collected from different steps of CHO antibody purification process. CHO DNA was spiked into different matrices, extracted, and quantified using the resDetect™ kits. The recovery acceptance criterion was 50–150%. The observed recoveries for all intermediate samples were approximately 100%.