The authors wish to acknowledge funding from the European Regional Development Fund &#8211; FNUSA-ICRC (no. CZ.1.05/ 1.1.00/ 02.0123), the American Heart Association Scientist Development Grant (AHA #06-35185N), and the National Institutes of Health (NIH #T32HL007111).

1. Synthesis of Magnetite Gel
<ol>
	<li>Wash all glassware by using concentrated hydrochloric acid followed by deionized water followed by ethyl alcohol. Allow to dry O/N, preferably in a drying oven. 
	CAUTION! hydrochloric acid is harmful &#8211; wear personal protective equipment and work in a fume hood; ethyl alcohol is harmful &#8211; wear personal protective equipment.</li>
	<li>Use a Dreschel bottle to de-gas 500 ml of deionized H2O by gently bubbling N2 gas for 30 mins.</li>
	<li>Set-...

<ol>
	<li>Burgess, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+delivery+of+neural+stem+cells+to+the+brain+using+MRI-guided+focused+ultrasound+to+disrupt+the+blood-brain+barrier.">Targeted delivery of neural stem cells to the brain using MRI-guided focused ultrasound to disrupt the blood-brain barrier.</a> PLoS One. 6 (11), e27877 (2011).</li><li>Nguyen, K. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mesenchymal+Stem+Cells+as+Targeted+Cell+Vehicles+to+Deliver+Drug-loaded+Nanoparticles+for+Cancer+Therapy.">Mesenchymal Stem Cells as Targeted Cell Vehicles to Deliver Drug-loaded Nanoparticles for Cancer Therapy.</a> J Nanomed Nanotechol. 4 (1), e128 (2013).</li><li>Kean, T. J., Lin, P., Caplan, A. I., Dennis, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MSCs:+Delivery+Routes+and+Engraftment,+Cell-Targeting+Strategies,+and+Immune+Modulation.">MSCs: Delivery Routes and Engraftment, Cell-Targeting Strategies, and Immune Modulation.</a> Stem Cells Int. , 732742 (2013).</li><li>Suzuki, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+cell+delivery+into+infarcted+rat+hearts+by+retrograde+intracoronary+infusion:+distribution,+dynamics,+and+influence+on+cardiac+function.">Targeted cell delivery into infarcted rat hearts by retrograde intracoronary infusion: distribution, dynamics, and influence on cardiac function.</a> Circulation. 110 (11 Suppl 1), II225-II230 (2004).</li><li>Garbern, J. C., Lee, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+stem+cell+therapy+and+the+promise+of+heart+regeneration.">Cardiac stem cell therapy and the promise of heart regeneration.</a> Cell Stem Cell. 12 (6), 689-698 (2013).</li><li>Duckers, H. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accelerated+vascular+repair+following+percutaneous+coronary+intervention+by+capture+of+endothelial+progenitor+cells+promotes+regression+of+neointimal+growth+at+long+term+follow-up:+final+results+of+the+Healing+II+trial+using+an+endothelial+progenitor+cell+capturing+stent+(Genous+R+stent).">Accelerated vascular repair following percutaneous coronary intervention by capture of endothelial progenitor cells promotes regression of neointimal growth at long term follow-up: final results of the Healing II trial using an endothelial progenitor cell capturing stent (Genous R stent).</a> EuroIntervention. 3 (3), 350-358 (2007).</li><li>Pan, Y., Du, X., Zhao, F., Xu, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+nanoparticles+for+the+manipulation+of+proteins+and+cells.">Magnetic nanoparticles for the manipulation of proteins and cells.</a> Chem Soc Rev. 41 (7), 2912-2942 (2012).</li><li>Huang, Z. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deep+magnetic+capture+of+magnetically+loaded+cells+for+spatially+targeted+therapeutics.">Deep magnetic capture of magnetically loaded cells for spatially targeted therapeutics.</a> Biomaterials. 31 (8), 2130-2140 (2010).</li><li>Shen, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+Magnetic+Intensities+for+Mesenchymal+Stem+Cell+Targeting+Therapy+on+Ischemic+Myocardial+Repair:+High+Magnetic+Intensity+Improves+Cell+Retention+but+Has+No+Additional+Functional+Benefit.">Comparison of Magnetic Intensities for Mesenchymal Stem Cell Targeting Therapy on Ischemic Myocardial Repair: High Magnetic Intensity Improves Cell Retention but Has No Additional Functional Benefit.</a> Cell Transplant. , (2014).</li><li>Cheng, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+antibody-linked+nanomatchmakers+for+therapeutic+cell+targeting.">Magnetic antibody-linked nanomatchmakers for therapeutic cell targeting.</a> Nat Commun. 5, 4880 (2014).</li><li>Vandergriff, A. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+of+cardiosphere-derived+stem+cells+with+ferumoxytol+nanoparticles+for+treating+rats+with+myocardial+infarction.">Magnetic targeting of cardiosphere-derived stem cells with ferumoxytol nanoparticles for treating rats with myocardial infarction.</a> Biomaterials. 35 (30), 8528-8539 (2014).</li><li>Huang, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+enhances+retrograde+cell+retention+in+a+rat+model+of+myocardial+infarction.">Magnetic targeting enhances retrograde cell retention in a rat model of myocardial infarction.</a> Stem Cell Res Ther. 4 (6), 149 (2013).</li><li>Chaudeurge, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Can+magnetic+targeting+of+magnetically+labeled+circulating+cells+optimize+intramyocardial+cell+retention.">Can magnetic targeting of magnetically labeled circulating cells optimize intramyocardial cell retention.</a> Cell Transplant. 21 (4), 679-691 (2012).</li><li>Cheng, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+enhances+engraftment+and+functional+benefit+of+iron-labeled+cardiosphere-derived+cells+in+myocardial+infarction.">Magnetic targeting enhances engraftment and functional benefit of iron-labeled cardiosphere-derived cells in myocardial infarction.</a> Circ Res. 106 (10), 1570-1581 (2010).</li><li>Yanai, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Focused+magnetic+stem+cell+targeting+to+the+retina+using+superparamagnetic+iron+oxide+nanoparticles.">Focused magnetic stem cell targeting to the retina using superparamagnetic iron oxide nanoparticles.</a> Cell Transplant. 21 (6), 1137-1148 (2012).</li><li>Ordidge, K. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coupled+cellular+therapy+and+magnetic+targeting+for+airway+regeneration.">Coupled cellular therapy and magnetic targeting for airway regeneration.</a> Biochem Soc Trans. 42 (3), 657-661 (2014).</li><li>El Haj, A. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+in+vitro+model+of+mesenchymal+stem+cell+targeting+using+magnetic+particle+labelling.">An in vitro model of mesenchymal stem cell targeting using magnetic particle labelling.</a> J Tissue Eng Regen Med. , (2012).</li><li>Vanecek, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Highly+efficient+magnetic+targeting+of+mesenchymal+stem+cells+in+spinal+cord+injury.">Highly efficient magnetic targeting of mesenchymal stem cells in spinal cord injury.</a> Int J Nanomedicine. 7, 3719-3730 (2012).</li><li>Sasaki, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Therapeutic+effects+with+magnetic+targeting+of+bone+marrow+stromal+cells+in+a+rat+spinal+cord+injury+model.">Therapeutic effects with magnetic targeting of bone marrow stromal cells in a rat spinal cord injury model.</a> Spine (Phila Pa 1976). 36 (12), 933-938 (2011).</li><li>Oshima, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhancement+of+bone+formation+in+an+experimental+bony+defect+using+ferumoxide-labelled+mesenchymal+stromal+cells+and+a+magnetic+targeting+system.">Enhancement of bone formation in an experimental bony defect using ferumoxide-labelled mesenchymal stromal cells and a magnetic targeting system.</a> J Bone Joint Surg Br. 92 (11), 1606-1613 (2010).</li><li>Luciani, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+of+iron-oxide-labeled+fluorescent+hepatoma+cells+to+the+liver.">Magnetic targeting of iron-oxide-labeled fluorescent hepatoma cells to the liver.</a> Eur Radiol. 19 (5), 1087-1096 (2009).</li><li>Oshima, S., Kamei, N., Nakasa, T., Yasunaga, Y., Ochi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhancement+of+muscle+repair+using+human+mesenchymal+stem+cells+with+a+magnetic+targeting+system+in+a+subchronic+muscle+injury+model.">Enhancement of muscle repair using human mesenchymal stem cells with a magnetic targeting system in a subchronic muscle injury model.</a> J Orthop Sci. 19 (3), 478-488 (2014).</li><li>Ohkawa, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+of+human+peripheral+blood+CD133++cells+for+skeletal+muscle+regeneration.">Magnetic targeting of human peripheral blood CD133+ cells for skeletal muscle regeneration.</a> Tissue Eng Part C Methods. 19 (8), 631-641 (2013).</li><li>Tefft, B. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetizable+Duplex+Steel+Stents+Enable+Endothelial+Cell+Capture.">Magnetizable Duplex Steel Stents Enable Endothelial Cell Capture.</a> Ieee T Magn. 49 (1), 463-466 (2013).</li><li>Uthamaraj, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+validation+of+a+novel+ferromagnetic+bare+metal+stent+capable+of+capturing+and+retaining+endothelial+cells.">Design and validation of a novel ferromagnetic bare metal stent capable of capturing and retaining endothelial cells.</a> ABME. 42 (12), 2416-2424 (2014).</li><li>Polyak, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+field+gradient+targeting+of+magnetic+nanoparticle-loaded+endothelial+cells+to+the+surfaces+of+steel+stents.">High field gradient targeting of magnetic nanoparticle-loaded endothelial cells to the surfaces of steel stents.</a> Proc Natl Acad Sci U.S.A. 105 (2), 698-703 (2008).</li><li>Pislaru, S. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetically+targeted+endothelial+cell+localization+in+stented+vessels.">Magnetically targeted endothelial cell localization in stented vessels.</a> J Am Coll Cardiol. 48 (9), 1839-1845 (2006).</li><li>Pislaru, S. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+forces+enable+rapid+endothelialization+of+synthetic+vascular+grafts.">Magnetic forces enable rapid endothelialization of synthetic vascular grafts.</a> Circulation. 114 (1 Suppl), 314-318 (2006).</li><li>Wang, Y. X., Xuan, S., Port, M., Idee, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+superparamagnetic+iron+oxide+nanoparticles+for+cellular+imaging+and+targeted+therapy+research.">Recent advances in superparamagnetic iron oxide nanoparticles for cellular imaging and targeted therapy research.</a> Curr Pharm Des. 19 (37), 6575-6593 (2013).</li><li>Yellen, B. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeted+drug+delivery+to+magnetic+implants+for+therapeutic+applications.">Targeted drug delivery to magnetic implants for therapeutic applications.</a> J Magn Magn Mater. 293 (1), 647-654 (2005).</li><li>Granot, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinically+viable+magnetic+poly(lactide-co-glycolide)+particles+for+MRI-based+cell+tracking.">Clinically viable magnetic poly(lactide-co-glycolide) particles for MRI-based cell tracking.</a> Magn Reson Med. , (2013).</li><li>Levy, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long+term+in+vivo+biotransformation+of+iron+oxide+nanoparticles.">Long term in vivo biotransformation of iron oxide nanoparticles.</a> Biomaterials. 32 (16), 3988-3999 (2011).</li><li>Mirshafiee, V., Mahmoudi, M., Lou, K., Cheng, J., Kraft, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+corona+significantly+reduces+active+targeting+yield.">Protein corona significantly reduces active targeting yield.</a> Chem Commun (Camb). 49 (25), 2557-2559 (2013).</li><li>Salvati, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transferrin-functionalized+nanoparticles+lose+their+targeting+capabilities+when+a+biomolecule+corona+adsorbs+on+the+surface.">Transferrin-functionalized nanoparticles lose their targeting capabilities when a biomolecule corona adsorbs on the surface.</a> Nat Nanotechnol. 8 (2), 137-143 (2013).</li><li>Landazuri, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+of+human+mesenchymal+stem+cells+with+internalized+superparamagnetic+iron+oxide+nanoparticles.">Magnetic targeting of human mesenchymal stem cells with internalized superparamagnetic iron oxide nanoparticles.</a> Small. 9 (23), 4017-4026 (2013).</li><li>Sun, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+labeling+of+endothelial+progenitor+cells+isolated+from+peripheral+blood+with+superparamagnetic+iron+oxide+nanoparticles.">In vitro labeling of endothelial progenitor cells isolated from peripheral blood with superparamagnetic iron oxide nanoparticles.</a> Mol Med Rep. 6 (2), 282-286 (2012).</li><li>Zhang, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+viability+of+transplanted+beta+cells+labeled+with+a+novel+contrast+agent+-+polyvinylpyrrolidone-coated+superparamagnetic+iron+oxide+nanoparticles+by+magnetic+resonance+imaging.">Detection of viability of transplanted beta cells labeled with a novel contrast agent - polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles by magnetic resonance imaging.</a> Contrast Media Mol Imaging. 7 (1), 35-44 (2012).</li><li>Song, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Labeling+efficacy+of+superparamagnetic+iron+oxide+nanoparticles+to+human+neural+stem+cells:+comparison+of+ferumoxides,+monocrystalline+iron+oxide,+cross-linked+iron+oxide+(CLIO)-NH2+and+tat-CLIO.">Labeling efficacy of superparamagnetic iron oxide nanoparticles to human neural stem cells: comparison of ferumoxides, monocrystalline iron oxide, cross-linked iron oxide (CLIO)-NH2 and tat-CLIO.</a> Korean J Radiol. 8 (5), 365-371 (2007).</li></ol>

As with any nanoparticle synthesis protocol, the purity of the reactant chemicals is critical for achieving high quality SPIONs that will have minimal cytotoxic effects. It is therefore important to purchase very pure reagents including oleic acid (&#8805;99%), iron(II) chloride tetrahydrate (&#8805;99.99%), iron(III) chloride (&#8805;99.99%), ethyl acetate (HPLC grade, &#8805;99.9%), hexane (HPLC grade, &#8805;97.0%), ammonium hydroxide (&#8805;99.99%), and sodium sulfate (&#8805;99.0%). It is of particular importance t...

Targeted delivery and capture of cells to specific sites within the body is desirable for a variety of biomedical applications. Delivery of neural stem cells to the brain by MRI-guided focused ultrasound has been proposed as a possible treatment option for neurodegenerative disease, traumatic brain injury, and stroke1. Mesenchymal stem cells are being studied for their ability to deliver anti-cancer drugs to tumors due to their natural tumor-tropic properties2,3. Cardiac stem cells have been delivered to the heart as a possible treatment for myocardial infarction4,5. Vascular stents have been developed with CD34 antibodies to capture circulating progenitor cells6. While promising, these cell targeting approaches present drawbacks including lack of cell specificity, inconsistent cell retention, and off-target cell delivery.
The overall goal of the current method is to enable magnetically directed targeting of cells for a variety of cell delivery and sorting applications. Magnetic targeting allows for controlled delivery of specific cells to a specific target site with minimal off-target effects7. The magnetic fields can be generated by implanted or external devices to safely direct the movement of magnetically-labeled cells within the body8. Numerous research efforts have focused on magnetically directed targeting of stem cells to injured tissues such as the heart9-14, retina15, lung16, skin17, spinal cord18,19, bone20, liver21, and muscle22,23 in order to improve regeneration outcomes.
Magnetic targeting of cells has also been studied extensively as a means to endothelialize implantable cardiovascular devices. A uniform and complete endothelium provides a barrier between the device and circulating blood elements to mitigate thrombosis and inflammation. Endothelial cells can be delivered to the device either prior to implantation or via the vascular system following implantation. In both cases, magnetic fields are used to capture cells to the surface of the device and retain the cells when subjected to the shear stress generated by circulating blood. Magnetic vascular stents24-27 and vascular grafts28 have both been fabricated and tested for this purpose.
Magnetic cell targeting requires a strategy for labeling cells with magnetic carrier particles. These particles can be bound to the surface of cells via antibodies or ligand/receptor pairs or they can be endocytosed into the cells. Superparamagnetic iron oxide nanoparticles (SPION) are biodegradable, biocompatible, and readily endocytosed by a variety of cell types29. These particles effectively render a cell responsive to magnetic fields and are naturally degraded over time. SPIONs provide a straightforward and safe means of magnetically labeling cells in culture for a variety of magnetic targeting and sorting applications. A method for synthesizing SPIONs with a magnetite (Fe3O4) core and poly(lactic-co-glycolic acid) (PLGA) shell is provided. In addition, a method for labeling cells in culture with SPIONs is provided.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Ammonium Hydroxide solution, 28% NH3 in H2O, &#8805;99.99% trace metal basis</td>
			<td>Sigma-Aldrich</td>
			<td>338818-100ML&#160;</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Dreschel bottle, 500 mL</td>
			<td>Ace Glass</td>
			<td>5516-16</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethyl Acetate, CHROMASOLVR Plus, for HPLC, 99.9%&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>650528-1L</td>
			<td>Harmful reagent - wear personal protective equipment &#38; work in fume hood</td>
		</tr>
		<tr>
			<td>Ethyl alcohol</td>
			<td>Sigma-Aldrich</td>
			<td>E7023</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Filter paper, 3 cm dia, grade 1</td>
			<td>Fisher</td>
			<td>09-805P</td>
			<td>For use with glass filter funnel</td>
		</tr>
		<tr>
			<td>Glass beakers, 1 L</td>
			<td>Fisher</td>
			<td>FB-101-1000</td>
			<td>For washing SPIONs</td>
		</tr>
		<tr>
			<td>Glass filter funnel, vacuum hose adapter, fits 24/40, 30 mL</td>
			<td>Fisher</td>
			<td>K954100-0344&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass vial caps</td>
			<td>Fisher</td>
			<td>03-391-46</td>
			<td>For use with glass vials</td>
		</tr>
		<tr>
			<td>Glass vials, 2 mL</td>
			<td>Fisher</td>
			<td>03-391-44</td>
			<td>For collecting magnetite gel &#38; SPIONs</td>
		</tr>
		<tr>
			<td>Hexane, CHROMASOLVR, for HPLC, &#8805;97.0% (GC)</td>
			<td>Sigma-Aldrich</td>
			<td>34859-1L&#160;</td>
			<td>Harmful reagent - wear personal protective equipment &#38; work in fume hood</td>
		</tr>
		<tr>
			<td>Hydrochloric acid</td>
			<td>Sigma-Aldrich</td>
			<td>H1758</td>
			<td>Harmful reagent - wear personal protective equipment &#38; work in fume hood</td>
		</tr>
		<tr>
			<td>Iron(II) chloride tetrahydrate, &#8805;99.99% trace metals basis&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>380024-5G</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Iron(III) chloride anhydrous, powder, &#8805;99.99% trace metals basis</td>
			<td>Sigma-Aldrich</td>
			<td>451649-1G</td>
			<td>Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Isomantle heater, 500 mL</td>
			<td>Voight Global</td>
			<td>EM0500/CEX1</td>
			<td></td>
		</tr>
		<tr>
			<td>Laboratory mixer</td>
			<td>Silverson</td>
			<td>L5M-A</td>
			<td></td>
		</tr>
		<tr>
			<td>Lyophilizer</td>
			<td>Labconco</td>
			<td>7670520</td>
			<td></td>
		</tr>
		<tr>
			<td>Microspatulas</td>
			<td>Fisher</td>
			<td>21-401-25A</td>
			<td>For transfering magnetite gel</td>
		</tr>
		<tr>
			<td>NdFeB magnet, 1 in x 1 in x 1 in</td>
			<td>Amazing Magnets</td>
			<td>C1000H-M</td>
			<td>Very strong magnet, handle with care</td>
		</tr>
		<tr>
			<td>Oleic acid, &#8805;99% (GC)</td>
			<td>Sigma-Aldrich</td>
			<td>O1008-5G&#160;</td>
			<td>Store in freezer; Harmful reagent - wear personal protective equipment</td>
		</tr>
		<tr>
			<td>Overhead stirrer</td>
			<td>IKA</td>
			<td>2572201</td>
			<td></td>
		</tr>
		<tr>
			<td>Overhead stirrer clamp</td>
			<td>IKA</td>
			<td>2664000</td>
			<td>For use with overhead stirrer</td>
		</tr>
		<tr>
			<td>Overhead stirrer H-stand</td>
			<td>IKA</td>
			<td>1412000</td>
			<td>For use with overhead stirrer</td>
		</tr>
		<tr>
			<td>Phosphate buffered saline</td>
			<td>Life Technologies</td>
			<td>10010-023</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic beakers, 250 mL</td>
			<td>Fisher</td>
			<td>02-591-28</td>
			<td></td>
		</tr>
		<tr>
			<td>PLGA PURASORB PDLG (75/25 blend)</td>
			<td>Purac</td>
			<td>PDLG 7502</td>
			<td>PDLG 7502A may be used as well; Store in freezer</td>
		</tr>
		<tr>
			<td>Pluronic F-127 powder, BioReagent, suitable for cell culture</td>
			<td>Sigma-Aldrich</td>
			<td>P2443-250G&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>PTFE expandable blade paddle, 8 mm dia</td>
			<td>SciQuip</td>
			<td>SP4018</td>
			<td></td>
		</tr>
		<tr>
			<td>PTFE vessel adapter, fits 24/40, 8 mm dia paddle</td>
			<td>Monmouth Scientific</td>
			<td>PTFE Vessel Adaptor A480</td>
			<td>For use with PTFE expandable blade paddle</td>
		</tr>
		<tr>
			<td>Recirculating chiller</td>
			<td>Clarkson</td>
			<td>696613</td>
			<td>For use with rotoevaporator</td>
		</tr>
		<tr>
			<td>Reflux condenser, fits 24/40, 250 mm</td>
			<td>Ace Glass</td>
			<td>5997-133</td>
			<td></td>
		</tr>
		<tr>
			<td>Rotoevaporator</td>
			<td>Clarkson</td>
			<td>216949</td>
			<td></td>
		</tr>
		<tr>
			<td>Round bottom flask, 50 mL, 24/40 joint</td>
			<td>Sigma-Aldrich</td>
			<td>Z414484</td>
			<td>For use with rotoevaporator</td>
		</tr>
		<tr>
			<td>Rubber septa, fits 24/40</td>
			<td>Ace Glass</td>
			<td>9096-56</td>
			<td></td>
		</tr>
		<tr>
			<td>Separatory funnel with stopper, 250 mL</td>
			<td>Fisher</td>
			<td>10-438E</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium sulfate ACS reagent, &#8805;99.0%, anhydrous, granular</td>
			<td>Sigma-Aldrich</td>
			<td>239313-500G&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Three neck round bottom flask, angled, 24/40 joints, 500 mL</td>
			<td>Ace Glass</td>
			<td>6948-16</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrasonic cleaner perforated pan</td>
			<td>Fisher</td>
			<td>15-335-20A</td>
			<td>For use with ultrasonic cleaner</td>
		</tr>
		<tr>
			<td>Ultrasonic cleaner, 2.8 L</td>
			<td>Fisher</td>
			<td>15-335-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum controller</td>
			<td>Clarkson</td>
			<td>216639</td>
			<td>For use with rotoevaporator (optional)</td>
		</tr>
		<tr>
			<td>Vacuum pump</td>
			<td>Clarkson</td>
			<td>219959</td>
			<td>For use with rotoevaporator</td>
		</tr>
	</tbody>
</table>

cell labeling and targeting with superparamagnetic iron oxide nanoparticles

Targeted delivery of cells and therapeutic agents would benefit a wide range of biomedical applications by concentrating the therapeutic effect at the target site while minimizing deleterious effects to off-target sites. Magnetic cell targeting is an efficient, safe, and straightforward delivery technique. Superparamagnetic iron oxide nanoparticles (SPION) are biodegradable, biocompatible, and can be endocytosed into cells to render them responsive to magnetic fields. The synthesis process involves creating magnetite (Fe3O4) nanoparticles followed by high-speed emulsification to form a poly(lactic-co-glycolic acid) (PLGA) coating. The PLGA-magnetite SPIONs are approximately 120 nm in diameter including the approximately 10 nm diameter magnetite core. When placed in culture medium, SPIONs are naturally endocytosed by cells and stored as small clusters within cytoplasmic endosomes. These particles impart sufficient magnetic mass to the cells to allow for targeting within magnetic fields. Numerous cell sorting and targeting applications are enabled by rendering various cell types responsive to magnetic fields. SPIONs have a variety of other biomedical applications as well including use as a medical imaging contrast agent, targeted drug or gene delivery, diagnostic assays, and generation of local hyperthermia for tumor therapy or tissue soldering.

Magnetite nanoparticles are approximately 10 nm in diameter as a result of stirring an aqueous solution of iron(III) chloride and iron(II) chloride tetrahydrate at 50 &#176;C and 1,000 rpm (Figure 1). These results demonstrate successful synthesis of magnetite nanoparticles. It is important to verify the size and shape of magnetite nanoparticles taken from a small sample of the batch when attempting the synthesis for the first time. Transmission electron microscopy (TEM) is the preferred method for visua...

Watch this Scientific Journal Video about Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles at JoVE.com

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Targeted cell delivery is useful in a variety of biomedical applications. The goal of this protocol is to use superparamagnetic iron oxide nanoparticles (SPION) to label cells and thereby enable magnetic cell targeting approaches for a high degree of control over cell delivery and localization.

Targeted delivery of cells and therapeutic agents would benefit a wide range of biomedical applications by concentrating the therapeutic effect at the ...

cell-labeling-targeting-with-superparamagnetic-iron-oxide

Research

JoVE Journal

Bioengineering

11.9K visualizações.  Mayo Clinic. Targeted cell delivery is useful in a variety of biomedical applications. The goal of this protocol is to use superparamagnetic iron oxide nanoparticles (SPION) to label cells and thereby enable magnetic cell targeting approaches for a high degree of control over cell delivery and localization.