The Filterprep: A simple and efficient approach for high-yield, high-purity plasmid DNA purification

Plasmid DNA purification remains a fundamental yet resource-intensive step in molecular biology and biotechnology. Conventional protocols often yield plasmids with suboptimal purity, while commercial kits, though efficient, are costly and use proprietary formulations with limited transparency for troubleshooting or customization. Here, we present Filterprep, a hybrid method combining classical ethanol precipitation with a single spin-column cleanup step, enabling rapid recovery of high-purity plasmid DNA with yields notably higher than those obtained using commercial kits, in approximately 40 min, with yields up to 5-fold greater than those of representative commercial midiprep kits under matched conditions. Filterprep offers a transparent, cost-effective, and scalable alternative, simplifying workflows and reducing hands-on time without compromising DNA quality. The purified plasmids are compatible with a variety of downstream applications, including mammalian cell transfection, protein expression, and reporter assays, while remaining stable for 12 months at -20 °C. With its balance of efficiency and practicality, Filterprep is well suited for high-throughput laboratories and resource-limited settings.