Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Abstract

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 (Fe 3 O 4 ) 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. Video LinkThe video component of this article can be found at

Innovative superparamagnetic iron-oxide nanoparticles coated with silica and conjugated with linoleic acid: Effect on tumor cell growth and viability

“…Cancer nanomedicine pays particular attention to superparamagnetic iron oxide nanoparticles (SPIONs), that can reach the tumor sites carrying chemotherapeutic drugs, nucleic acids, monoclonal antibodies, viral vectors engineered with therapeutic suicide genes or shRNAs [1,2,3]. SPIONs are also used for diagnostic assays, generation of local hyperthermia for tumor therapy or tissue repair by delivering stem cells [4,5]. In fact, SPIONs can be combined with contrast fluorescent agents to improve cancer cell imaging [1].…”

Magnetizable stent-grafts enable endothelial cell capture

“…SPIONs were synthesized by coating magnetite (Fe 3 O 4 ) with poly(lactic-co-glycolic acid) (PLGA) as previously described [6]. Briefly, magnetite nanoparticles approximately 10 nm in diameter were synthesized by stirring an aqueous solution of iron(II) chloride tetrahydrate and iron(III) chloride at 1,000 RPM and 50 °C.…”

“…One day prior to use, BOECs were labeled with SPIONs by adding to cell culture medium at a concentration of 200 µg/mL and incubating overnight at 37 °C as previously described [6]. BOECs endocytose the SPION particles and store them within cytoplasmic endosomes as we have shown previously [9].…”

“…We have developed a process for synthesizing superparamagnetic iron oxide nanoparticles (SPION) and using them to label blood outgrowth endothelial cells (BOEC) [6]. Furthermore, we have demonstrated that SPION-labeled BOECs can be targeted to magnetic devices including vascular grafts [7] and stents [8–10].…”

Nanoparticles in biomedical applications

“…A lot of literature have focused on iron oxide nanoparticles because of their superior chemical, biological and magnetic properties including chemical stability, non-toxicity, biocompatibility, high saturation magnetisation and high magnetic susceptibility [5][6][7][8]. These properties allow for its use in many biomedical applications; bioimaging 34,41,56,62], hyperthermia [20,21,[31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46]55], drug delivery , cell labelling [26,70] and gene delivery [71][72][73][74][75][76][77]. From our most recent review, it was seen that other magnetic nanomaterials such as Fe-Co, Cu-Ni, Fe-Ni, Co-Fe 2 O 4 and Mn-Fe 2 O 4 , nanoparticles are being investigated for use in bioimaging [78][79][80][81][82][83][84][85][86]…”