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Exploiting Size-Dependent Drag and Magnetic Forces for Size-Specific Separation of Magnetic Nanoparticles.

Rogers HB, Anani T, Choi YS, Beyers RJ, David AE - Int J Mol Sci (2015)

Bottom Line: Magnetic field-flow fractionation, however, was found to be an effective method for the separation of polydisperse suspensions of iron oxide nanoparticles with diameters greater than 20 nm.Both transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis were used to confirm the size of the MNPs.Further development of this work could lead to MNPs with the narrow size distributions necessary for their in vitro and in vivo optimization.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Engineering, Auburn University, 212 Ross Hall, Auburn, AL 36849, USA. hunterrogers2014@u.northwestern.edu.

ABSTRACT
Realizing the full potential of magnetic nanoparticles (MNPs) in nanomedicine requires the optimization of their physical and chemical properties. Elucidation of the effects of these properties on clinical diagnostic or therapeutic properties, however, requires the synthesis or purification of homogenous samples, which has proved to be difficult. While initial simulations indicated that size-selective separation could be achieved by flowing magnetic nanoparticles through a magnetic field, subsequent in vitro experiments were unable to reproduce the predicted results. Magnetic field-flow fractionation, however, was found to be an effective method for the separation of polydisperse suspensions of iron oxide nanoparticles with diameters greater than 20 nm. While similar methods have been used to separate magnetic nanoparticles before, no previous work has been done with magnetic nanoparticles between 20 and 200 nm. Both transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis were used to confirm the size of the MNPs. Further development of this work could lead to MNPs with the narrow size distributions necessary for their in vitro and in vivo optimization.

No MeSH data available.


Related in: MedlinePlus

(a) Digital image of the sequence of magnets used for the simulation and validation experiments and the magnetic field map generated, using data from the manufacturer, for a series of five non-interacting ¼′′ diameter cylindrical magnets; (b) DLS size distribution of original iron oxide nanoparticle suspension; Predicted particle trajectories and resulting size distributions for original MNP (red), Fraction 1 (blue) and Fraction 2 (green) for magnet distances of (c) 7.5 mm; (d) 10 mm; and (e) 11.5 mm. Particle trajectory data sets based on MNP size of 44, 51, 59, 68, 79, 91, 106, 122, 142, 164, 190, 220, 255, 295, 342 and 396 nm.
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ijms-16-20001-f002: (a) Digital image of the sequence of magnets used for the simulation and validation experiments and the magnetic field map generated, using data from the manufacturer, for a series of five non-interacting ¼′′ diameter cylindrical magnets; (b) DLS size distribution of original iron oxide nanoparticle suspension; Predicted particle trajectories and resulting size distributions for original MNP (red), Fraction 1 (blue) and Fraction 2 (green) for magnet distances of (c) 7.5 mm; (d) 10 mm; and (e) 11.5 mm. Particle trajectory data sets based on MNP size of 44, 51, 59, 68, 79, 91, 106, 122, 142, 164, 190, 220, 255, 295, 342 and 396 nm.

Mentions: A Matlab simulation was developed to study the feasibility of separating magnetic nanoparticles of sizes between 50 and 400 nm using the proposed approach. The simulation was based on a proposed experimental design that included 1.6 mm I.D. tubing of length 60 mm running parallel to a magnet, as shown in Figure 1. A Y-split at the end of the tubing (x = 60 mm) facilitated separation of MNPS based on their y-position. If the final y-position of a particle was greater than zero (center of the channel is at y = 0) then it was considered to be in Fraction 1, while those at or below the line were considered to be in Fraction 2. The magnetic field was derived from a series of five ¼′′ diameter × ¼′′ length cylindrical neodymium magnets (Cat No.: D44-N52, K & J Magnetics, Pipersville, PA, USA) spaced 7.5 mm apart, as shown in Figure 2a. The magnetic flux density map (Figure 2a) was generated using data provided by the manufacturer and assuming non-interacting magnets.


Exploiting Size-Dependent Drag and Magnetic Forces for Size-Specific Separation of Magnetic Nanoparticles.

Rogers HB, Anani T, Choi YS, Beyers RJ, David AE - Int J Mol Sci (2015)

(a) Digital image of the sequence of magnets used for the simulation and validation experiments and the magnetic field map generated, using data from the manufacturer, for a series of five non-interacting ¼′′ diameter cylindrical magnets; (b) DLS size distribution of original iron oxide nanoparticle suspension; Predicted particle trajectories and resulting size distributions for original MNP (red), Fraction 1 (blue) and Fraction 2 (green) for magnet distances of (c) 7.5 mm; (d) 10 mm; and (e) 11.5 mm. Particle trajectory data sets based on MNP size of 44, 51, 59, 68, 79, 91, 106, 122, 142, 164, 190, 220, 255, 295, 342 and 396 nm.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4581337&req=5

ijms-16-20001-f002: (a) Digital image of the sequence of magnets used for the simulation and validation experiments and the magnetic field map generated, using data from the manufacturer, for a series of five non-interacting ¼′′ diameter cylindrical magnets; (b) DLS size distribution of original iron oxide nanoparticle suspension; Predicted particle trajectories and resulting size distributions for original MNP (red), Fraction 1 (blue) and Fraction 2 (green) for magnet distances of (c) 7.5 mm; (d) 10 mm; and (e) 11.5 mm. Particle trajectory data sets based on MNP size of 44, 51, 59, 68, 79, 91, 106, 122, 142, 164, 190, 220, 255, 295, 342 and 396 nm.
Mentions: A Matlab simulation was developed to study the feasibility of separating magnetic nanoparticles of sizes between 50 and 400 nm using the proposed approach. The simulation was based on a proposed experimental design that included 1.6 mm I.D. tubing of length 60 mm running parallel to a magnet, as shown in Figure 1. A Y-split at the end of the tubing (x = 60 mm) facilitated separation of MNPS based on their y-position. If the final y-position of a particle was greater than zero (center of the channel is at y = 0) then it was considered to be in Fraction 1, while those at or below the line were considered to be in Fraction 2. The magnetic field was derived from a series of five ¼′′ diameter × ¼′′ length cylindrical neodymium magnets (Cat No.: D44-N52, K & J Magnetics, Pipersville, PA, USA) spaced 7.5 mm apart, as shown in Figure 2a. The magnetic flux density map (Figure 2a) was generated using data provided by the manufacturer and assuming non-interacting magnets.

Bottom Line: Magnetic field-flow fractionation, however, was found to be an effective method for the separation of polydisperse suspensions of iron oxide nanoparticles with diameters greater than 20 nm.Both transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis were used to confirm the size of the MNPs.Further development of this work could lead to MNPs with the narrow size distributions necessary for their in vitro and in vivo optimization.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Engineering, Auburn University, 212 Ross Hall, Auburn, AL 36849, USA. hunterrogers2014@u.northwestern.edu.

ABSTRACT
Realizing the full potential of magnetic nanoparticles (MNPs) in nanomedicine requires the optimization of their physical and chemical properties. Elucidation of the effects of these properties on clinical diagnostic or therapeutic properties, however, requires the synthesis or purification of homogenous samples, which has proved to be difficult. While initial simulations indicated that size-selective separation could be achieved by flowing magnetic nanoparticles through a magnetic field, subsequent in vitro experiments were unable to reproduce the predicted results. Magnetic field-flow fractionation, however, was found to be an effective method for the separation of polydisperse suspensions of iron oxide nanoparticles with diameters greater than 20 nm. While similar methods have been used to separate magnetic nanoparticles before, no previous work has been done with magnetic nanoparticles between 20 and 200 nm. Both transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis were used to confirm the size of the MNPs. Further development of this work could lead to MNPs with the narrow size distributions necessary for their in vitro and in vivo optimization.

No MeSH data available.


Related in: MedlinePlus