title: Promoting DNA loading on magnetic nanoparticles using a DNA condensation strategy.
abstract: Maximizing DNA loading on magnetic nanoparticles (MNPs) is crucial for their successful utilization in gene transfer, DNA isolation, and bio-analytical applications. This enhancement is typically achieved by altering particle size and surfaces as well as charge density and ionic strength. We demonstrate a novel route for promoting DNA loading on amino-modified silica-coated magnetic nanoparticles (ASMNPs) by prior condensation of elongated DNA to a compact globule before adsorption. The enhanced DNA-loading capacity, as demonstrated by a reduction in the number of ASMNPs needed to achieve complexation, was presumably due to the elimination of DNA wrapping around nanoparticles and substantially reduced electrostatic interactions of DNA with nanoparticles because the compacted DNA globule conformation decreases its exposed surface charge. The maximum loading capacity of ASMNPs for condensed DNA was 4.4 times greater than that for elongated coiled DNA, achieving the highest ever reported value of 385 μg mg(-1). Practical applications for plasmid DNA isolation from cleared lysate confirmed the reliability of the proposed method.
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Shan
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China.
authors.forename: Youjun
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China.
authors.forename: Mengyu
authors.initials: M
authors.lastname: Guo
authors.affiliation: Department of Physics, Acadia University, Wolfville, NS, Canada.
authors.forename: J Craig
authors.initials: JC
authors.lastname: Bennett
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China.
authors.forename: Xianghai
authors.initials: X
authors.lastname: Li
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China.
authors.forename: Hefeng
authors.initials: H
authors.lastname: Tian
authors.affiliation: Verschuren Centre for Sustainability in Energy and the Environment, Cape Breton University, Sydney B1P 6 L2, Canada.
authors.forename: Ken
authors.initials: K
authors.lastname: Oakes
authors.affiliation: Verschuren Centre for Sustainability in Energy and the Environment, Cape Breton University, Sydney B1P 6 L2, Canada.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China. Electronic address: hqming@sicau.edu.cn.
authors.forename: Qianming
authors.initials: Q
authors.lastname: Huang
authors.affiliation: Faculty of Science, Sichuan Agricultural University, Yaan 625014, China. Electronic address: chp666@aliyun.com.
authors.forename: Huaping
authors.initials: H
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D000588:Amines / Q000737:chemistry; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D018014:Gene Transfer Techniques; D007700:Kinetics; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D009690:Nucleic Acid Conformation; D009994:Osmolar Concentration; D010316:Particle Size; D010957:Plasmids / Q000737:chemistry* / Q000378:metabolism; D011092:Polyethylene Glycols / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D055672:Static Electricity
chemical_list: D000588:Amines; D058185:Magnetite Nanoparticles; D011092:Polyethylene Glycols; D012822:Silicon Dioxide; D004247:DNA
keywords: ASMNPs; Adsorption; Coil DNA; DNA condensation; Elongated DNA; PEG