title: Particle-by-Particle Charge Analysis of DNA-Modified Nanoparticles Using Tunable Resistive Pulse Sensing.
abstract: Resistive pulse sensors, RPS, are allowing the transport mechanism of molecules, proteins and even nanoparticles to be characterized as they traverse pores. Previous work using RPS has shown that the size, concentration and zeta potential of the analyte can be measured. Here we use tunable resistive pulse sensing (TRPS) which utilizes a tunable pore to monitor the translocation times of nanoparticles with DNA modified surfaces. We start by demonstrating that the translocation times of particles can be used to infer the zeta potential of known standards and then apply the method to measure the change in zeta potential of DNA modified particles. By measuring the translocation times of DNA modified nanoparticles as a function of packing density, length, structure, and hybridization time, we observe a clear difference in zeta potential using both mean values and population distributions as a function of the DNA structure. We demonstrate the ability to resolve the signals for ssDNA, dsDNA, small changes in base length for nucleotides between 15 and 40 bases long, and even the discrimination between partial and fully complementary target sequences. Such a method has potential and applications in sensors for the monitoring of nanoparticles in both medical and environmental samples.
authors.affiliation: Department of Chemistry, School of Science, Loughborough University , Loughborough, Leicestershire LE11 3TU, United Kingdom.
authors.forename: Emma L C J
authors.initials: EL
authors.lastname: Blundell
authors.affiliation: Izon Science Limited , 8C Homersham Place, PO Box 39168, Burnside, Christchurch 8053, New Zealand.|School of Mathematics and Physics, The University of Queensland , Brisbane 4072, Australia.
authors.forename: Robert
authors.initials: R
authors.lastname: Vogel
authors.affiliation: Department of Chemistry, School of Science, Loughborough University , Loughborough, Leicestershire LE11 3TU, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: Platt
mesh_terms: D004247:DNA / Q000737:chemistry*; D055664:Electrochemical Techniques; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D009693:Nucleic Acid Hybridization; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D011137:Polystyrenes / Q000737:chemistry*; D019809:Streptavidin / Q000737:chemistry
chemical_list: D058185:Magnetite Nanoparticles; D009838:Oligodeoxyribonucleotides; D011137:Polystyrenes; D004247:DNA; D019809:Streptavidin