title: Intraluminal magnetisation of bowel by ferromagnetic particles for retraction and manipulation by magnetic probes.
abstract: Feasibility studies are needed to demonstrate that safe and effective manipulation of bowel during Minimal Access Surgery (MAS) can be obtained by use of magnetic force. This paper characterises two classes of magnetic particles: stainless steel microparticles (SS-μPs) and iron oxide nanoparticles (IO-nPs) in terms of their magnetisation, chemical composition, crystallinity, morphology and size distribution. Both magnetic particles were dispersed in a high viscosity biological liquid for intraluminal injection of bowel. Ex vivo porcine bowel segments were then retracted by permanent magnetic probes of 5.0 and 10mm diameter. Strong retraction forces reaching 6N maximum were obtained by magnetic fluid based on dispersion of SS-μPs. In contrast, the IO-nP-based magnetic liquid generated less attraction force, due to both lower magnetic and solution properties of the IO-nPs. The comparison of the two particles allowed the identification of the rules to engineer the next generation of particles. The results with SS-μPs provide proof on concept that intraluminal injection of magnetic fluid can generate sufficient force for efficient bowel retraction. Thereafter we shall carry out in vivo animal studies for efficacy and safety of both types of ferrofluids.
authors.affiliation: Institute for Medical Science and Technology, University of Dundee, Dundee, UK.
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Physics and Astronomy (SUPA), University of St Andrews, St Andrews, UK. Electronic address: Pascal.Andre@st-andrews.ac.uk.
authors.forename: P
authors.initials: P
authors.lastname: André
authors.affiliation: Institute for Medical Science and Technology, University of Dundee, Dundee, UK.
authors.forename: D
authors.initials: D
authors.lastname: McLean
authors.affiliation: Institute for Medical Science and Technology, University of Dundee, Dundee, UK.
authors.forename: S I
authors.initials: SI
authors.lastname: Brown
authors.affiliation: School of Chemistry (EaStChem) and School of Biology, University of St Andrews, St Andrews, UK.
authors.forename: G J
authors.initials: GJ
authors.lastname: Florence
authors.affiliation: Institute for Medical Science and Technology, University of Dundee, Dundee, UK. Electronic address: alfred@acuschieri.com.
authors.forename: A
authors.initials: A
authors.lastname: Cuschieri
mesh_terms: D000818:Animals; D005290:Ferric Compounds / Q000737:chemistry; D007422:Intestines / Q000601:surgery*; D059346:Magnets; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation*; D053758:Nanoparticles; D013552:Swine
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide
keywords: Characterisation; Magnetic bowel retraction; Magnetic particles; Minimal access surgery (MAS); Physical properties