Tangential Flow Ultrafiltration Allows Purification and Concentration of Lauric Acid-/Albumin-Coated Particles for Improved Magnetic Treatment.
Superparamagnetic iron oxide nanoparticles (SPIONs) are frequently used for drug targeting, hyperthermia and other biomedical purposes. Recently, we have reported the synthesis of lauric acid-/albumin-coated iron oxide nanoparticles SEON(LA-BSA), which were synthesized using excess albumin. For optimization of magnetic treatment applications, SPION suspensions need to be purified of excess surfactant and concentrated. Conventional methods for the purification and concentration of such ferrofluids often involve high shear stress and low purification rates for macromolecules, like albumin. In this work, removal of albumin by low shear stress tangential ultrafiltration and its influence on SEON(LA-BSA) particles was studied. Hydrodynamic size, surface properties and, consequently, colloidal stability of the nanoparticles remained unchanged by filtration or concentration up to four-fold (v/v). Thereby, the saturation magnetization of the suspension can be increased from 446.5 A/m up to 1667.9 A/m. In vitro analysis revealed that cellular uptake of SEON(LA-BSA) changed only marginally. The specific absorption rate (SAR) was not greatly affected by concentration. In contrast, the maximum temperature Tmax in magnetic hyperthermia is greatly enhanced from 44.4 °C up to 64.9 °C by the concentration of the particles up to 16.9 mg/mL total iron. Taken together, tangential ultrafiltration is feasible for purifying and concentrating complex hybrid coated SPION suspensions without negatively influencing specific particle characteristics. This enhances their potential for magnetic treatment.
Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, 91054 Erlangen, Germany. jan.zaloga@uk-erlangen.de.
Jan
J
Zaloga
Institute for Diagnostic and Interventional Radiology, University Hospital Jena, 07747 Jena, Germany. Marcus.Stapf@med.uni-jena.de.
Marcus
M
Stapf
Chair of Magnetofluiddynamics, Measuring and Automation Technology, Technische Universität Dresden, 01069 Dresden, Germany. johannes.nowak@tu-dresden.de.
Johannes
J
Nowak
Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, 91054 Erlangen, Germany. marina.poettler@uk-erlangen.de.
Marina
M
Pöttler
Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, 91054 Erlangen, Germany. ralf.friedrich@uk-erlangen.de.
Ralf P
RP
Friedrich
Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, 91054 Erlangen, Germany. rainer.tietze@uk-erlangen.de.
Rainer
R
Tietze
Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, 91054 Erlangen, Germany. stefan.lyer@uk-erlangen.de.
Stefan
S
Lyer
Division of Pharmaceutics, Friedrich Alexander University Erlangen-Nuremberg, 91058 Erlangen, Germany. geoff.lee@fau.de.
Geoffrey
G
Lee
Chair of Magnetofluiddynamics, Measuring and Automation Technology, Technische Universität Dresden, 01069 Dresden, Germany. stefan.odenbach@tu-dresden.de.
Stefan
S
Odenbach
Institute for Diagnostic and Interventional Radiology, University Hospital Jena, 07747 Jena, Germany. Ingrid.Hilger@med.uni-jena.de.
Ingrid
I
Hilger
Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, 91054 Erlangen, Germany. c.alexiou@web.de.
Christoph
C
Alexiou
D000818:Animals; D002417:Cattle; D003102:Colloids / Q000737:chemistry / Q000302:isolation & purification; D006801:Humans; D006979:Hyperthermia, Induced; D019169:Jurkat Cells; D007850:Lauric Acids / Q000737:chemistry* / Q000302:isolation & purification; D008280:Magnetics; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000302:isolation & purification; D013499:Surface Properties; D014462:Ultrafiltration / Q000379:methods*
D003102:Colloids; D007850:Lauric Acids; D058185:Magnetite Nanoparticles; C030358:lauric acid; D012710:Serum Albumin, Bovine
hyperthermia; nanoparticle concentration; nanoparticle purification; specific absorption rate (SAR); superparamagnetic iron oxide  nanoparticles (SPIONs); tangential ultrafiltration