A one step method for isolation of genomic DNA using multi-amino modified magnetic nanoparticles

A simple and efficient approach for the rapid extraction of genomic DNA from blood using various amino-modified magnetic nanoparticles (AMNPs) has been described. The salmon sperm DNA was isolated from aqueous solution based on electrostatic interaction between the positively charged amino-groups of AMNPs and the negatively charged phosphate groups of the DNA. The results of ultraviolet-visible (UV-Vis) spectrometry showed that increasing number of amino groups on the AMNPs surface resulted in an improvement in DNA adsorption efficiency. Several variables including the extraction pH, adsorption time, ionic strength and quantity of AMNPs were optimized to achieve the best extraction efficiency with the proposed method. Acceptable adsorption efficiency of 92% and recovery of 91% were achieved using multi-amino modified MNPs (mAMNPs) with an extraction time of 10 min and an overall processing time of 30 min. The mAMNPs enabled genomic DNA capture from human whole blood, and the resulting mAMNP/DNA complexes could be directly used as templates for PCR amplification without the need for complex and time-consuming DNA elution and purification steps. Our results imply that this method can be used as an effective strategy for genomic DNA extraction and may be extended to other types of biological samples.