Increased accumulation of magnetic nanoparticles by magnetizable implant materials for the treatment of implant-associated complications
Creators: name: Angrisani, Nina
name: Foth, Franziska
name: Kietzmann, Manfred
name: Schumacher, Stephan
name: Angrisani, Gian Luigi
name: Christel, Anne
name: Behrens, Peter
name: Reifenrath, Janin
Publisher: name: London : BioMed Central Ltd.
Year: 2013
Subjects: subject: Implant directed magnetic drug targeting
subject: In vitro
subject: Magnetic field strength
subject: Martensitic steel
subject: Applied magnetic fields
subject: External magnetic field
subject: In-vitro
subject: Magnetic drug targeting
subject: Magnetic field strengths
subject: Magnetic nano-particles
subject: Magnetic nanoparti cles (MNPs)
subject: Orthopaedic implants
subject: Bone
subject: Magnetic fields
subject: Magnets
subject: Nanoparticles
subject: Orthopedics
subject: Platelets
subject: Electromagnetic field effects
subject: magnetic nanoparticle
subject: stainless steel
subject: article
subject: blood flow velocity
subject: cell volume
subject: flow
subject: magnetic field
subject: orthopedic implant
subject: orthopedic surgery
subject: thrombocyte
subject: Animals
subject: Bone Plates
subject: Ferrosoferric Oxide
subject: Humans
subject: Magnetic Fields
subject: Magnetite Nanoparticles
subject: Models, Biological
subject: Rheology
subject: Stainless Steel
subject: Dewey Decimal Classification::500 | Naturwissenschaften::570 | Biowissenschaften, Biologie
subject: Dewey Decimal Classification::600 | Technik::610 | Medizin, Gesundheit

description: Background: In orthopaedic surgery, accumulation of agents such as anti-infectives in the bone as target tissue is difficult. The use of magnetic nanoparticles (MNPs) as carriers principally enables their accumulation via an externally applied magnetic field. Magnetizable implants are principally able to increase the strength of an externally applied magnetic field to reach also deep-seated parts in the body. Therefore, the integration of bone-addressed therapeutics in MNPs and their accumulation at a magnetic orthopaedic implant could improve the treatment of implant related infections. In this study a martensitic steel platelet as implant placeholder was used to examine its accumulation and retention capacity of MNPs in an in vitro experimental set up considering different experimental frame conditions as magnet quantity and distance to each other, implant thickness and flow velocity.Results: The magnetic field strength increased to approximately 112% when a martensitic stainless steel platelet was located between the magnet poles. Therewith a significantly higher amount of magnetic nanoparticles could be accumulated in the area of the platelet compared to the sole magnetic field. During flushing of the tube system mimicking the in vivo blood flow, the magnetized platelet was able to retain a higher amount of MNPs without an external magnetic field compared to the set up with no mounted platelet during flushing of the system. Generally, a higher flow velocity led to lower amounts of accumulated MNPs. A higher quantity of magnets and a lower distance between magnets led to a higher magnetic field strength. Albeit not significantly the magnetic field strength tended to increase with thicker platelets.Conclusion: A martensitic steel platelet significantly improved the attachment of magnetic nanoparticles in an in vitro flow system and therewith indicates the potential of magnetic implant materials in orthopaedic surgery. The use of a remanent magnetic implant material could improve the efficiency of capturing MNPs especially when the external magnetic field is turned off thus facilitating and prolonging the effect. In this way higher drug levels in the target area might be attained resulting in lower inconveniences for the patient.