A Rapid and Economic In-House DNA Purification Method Using Glass Syringe Filters

Yun-Cheol Kim,Sherie L Morrison

doi:10.1371/journal.pone.0007750

Abstract

BackgroundPurity, yield, speed and cost are important considerations in plasmid purification, but it is difficult to achieve all of these at the same time. Currently, there are many protocols and kits for DNA purification, however none maximize all four considerations.Methodology/Principal FindingsWe now describe a fast, efficient and economic in-house protocol for plasmid preparation using glass syringe filters. Plasmid yield and quality as determined by enzyme digestion and transfection efficiency were equivalent to the expensive commercial kits. Importantly, the time required for purification was much less than that required using a commercial kit.Conclusions/SignificanceThis method provides DNA yield and quality similar to that obtained with commercial kits, but is more rapid and less costly.

Highlights

Traditional plasmid DNA purification methods all have some limitations[1]
For convenience we primarily used the ready-made glass syringe filters, we found that filter discs placed in a holder yield the same result
We found that each glass syringe filter captures plasmid DNA until it reaches its maximum binding capacity after which unbound plasmid DNA goes to the filter where it is bound (Figure. 2(A))

Summary

Introduction

Traditional plasmid DNA purification methods all have some limitations[1]. Some are fast and allow isolation of nucleic acids within an hour[2], but speed usually comes at the price of reduced yield and/ or purity[3,4]. Many commercial DNA purification kits including QIAEX II Gel Extraction Kit (Qiagen, Valencia, CA) have been developed based on the fact that DNA binds to glass milk and diatomaceous earths in the presence of chaotropic agents[6,7]. Even though these kits are efficient, shearing forces due to fine particles may cause DNA breakage. Customized anion exchange resins provide efficient DNA purification, they are only available as high priced commercial kits available from vendors including Qiagen and Mackerey & Nagel. There are many protocols and kits for DNA purification, none maximize all four considerations

Methods

Results

Conclusion