Results and discussion

Mean cfDNA concentrations in the eluates were determined to be 8.30 ng/μL for samples extracted with the QIAamp kit and 11.15 ng/μL for samples extracted with the Apostle kit when measured with the Qubit assay (Figure 1A). This illustrates a 34.3% higher yield when using the Apostle kit as compared to the QIAamp kit.

When evaluating the contents of specific genes in the eluate, the Apostle purification displayed a higher yield than QIAamp (Figure 1B). 8358 DNAJC5G positive droplets were detected in the Apostle samples compared to 7269 droplets in the QIAamp samples. Similarly, 10849 ACTG1 droplets were detected in the Apostle-extracted samples versus 9463 droplets detected in the QIAamp-extracted samples. This data demonstrates an average of 14.8% higher yield using the Apostle kit.

Finally, when evaluating cfDNA fragments via the Agilent bioanalyzer instrument, the Apostle kit demonstrated the highest yield (Figure 1C and D). Mononucleosomal cfDNA concentration in the eluate of Apostle samples was estimated to be 10.64 ng/μL versus 6.26 ng/μL in the eluate of QIAamp samples. The dinucleosomal cfDNA concentration was low for both kits, with 0.13 ng/μL recorded for Apostle samples and 0.24 ng/μL for QIAamp samples. This indicates a slightly better purification of dinucleosomal cfDNA using QIAamp; however, this could also be an artifact given the low concentrations. The Apostle mononucleosomal cfDNA yield was 70.0% higher than the yield for the QIAamp samples.

Publication: Comparative analysis of cell-free DNA extraction efficiency from plasma.  Beckman Coulter Life Sciences. Indianapolis, IN. Technical Note 2022.

A summary provided in Table 2 shows the consistently higher yield achieved by the Apostle MiniMax High Efficiency cfDNA Isolation Kit as compared to the QIAamp® circulating nucleic acid kit. The average 40% improvement in yield underscores the importance of extraction kit selection in cfDNA assay development and highlights the potential impact of cfDNA isolation efficiency in ctDNA detection.

Publication: Comparative analysis of cell-free DNA extraction efficiency from plasma.  Beckman Coulter Life Sciences. Indianapolis, IN. Technical Note 2022.

(Figure 4) - "Most notably, the Apostle particles outperformed all others, achieving almost 2-fold higher recovery yields than the particles supplied in the Qiagen kit. "

Publication:  High-throughput sample processing for methylation analysis in an automated, enclosed environment.  Stark et al. SLAS Technology 2022; 27(3):172-179. 

Publication:  Optimization of high-volume cell free DNA extraction and end-to-end automation for TSO 500 ctDNA library prep [abstract]. Nripesh Prasad, Rachel Rock, Rebecca Beatty, Melanie Robinson, Dineen Wildman, Michael Sykes, Boris Umylny, Thomas Halsey. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2298. 

Figure 1. cfDNA extraction method affects allele frequency (AF%). EGFR L858R standards with AF% of 0.3%, 1.0%, and 3.0% were spiked into plasma and isolated using Product A (red) or Apostle MiniMax cfDNA isolation kit (blue and green). The eluates were analyzed by NGS (performed by the Institute B) following standard protocol and AF% calculated using their established workflow. cfDNA isolated by Apostle MiniMax cfDNA isolation kit shows higher concordance between detected AF% and expected AF%.

Publication: cfDNA Extraction Efficiency Affects NGS Data.   Beckman Coulter Life Sciences. Indianapolis, IN. Technical Note 2020.

(Figure 1) "For each tube the Apostle MiniMax extracted higher total yield of DNA. "

Publication: cfDNA Extraction from Plasma for Liquid Biopsy: Apostle MiniMaxTM High Efficiency cfDNA Isolation Kit. Beckman Coulter Life Sciences, Data Sheet. 2019. 

(Note: Table 13 referenced below in this diploma thesis shows that Apostle MiniMax yields the greatest number of analyzable drops in the digital PCR.)

Publication. Optimalizace digitální polymerázové řetězové reakce pro aplikaci v neinvazivní prenatální diagnostice (Optimization of digital polymerase chain reaction for application in non-invasive prenatal diagnostics) Author: Šenkyřík, Pavel; Advisor: Korabečná, Marie; Referee: Vodička, Radek; Faculty / Institute: Faculty of Science; Discipline: Anthropology and Human Genetics; Department: Department of Anthropology and Human Genetics; Date of defense: 13. 9. 2022; Publisher: Univerzita Karlova, Přírodovědecká fakulta;  Language: Czech