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The Leveäniemi iron oxide apatite (IOA) deposit, mined by LKAB, is located in Norrbotten, northern Sweden. The deposit has a partially more complex mineralogy than the neighbouring and more famous IOA deposits of Kiirunavaara and Malmberget. The Leveäniemi deposit contains comparatively more ore containing both magnetite and hematite but also maghemite and with slightly different trace element chemistry of the iron oxide minerals. Hematite is currently not considered a valuable mineral in the Svappavaara mineral processing and in the magnetite concentrate titanium and vanadium are considered to be penalty elements. Ore samples were collected from selected drill cores and from these polished thin sections were prepared that were investigated by optical microscopy, EPMA, and FE-SEM-EDS. Investigations focused on iron oxide mineralogy and mineral chemistry with special consideration to titanium and vanadium as those elements are considered deleterious in subsequent blast furnace or direct reduction processes. Investigations revealed that magnetite is the predominant mineral with secondary hematite being the second most abundant iron oxide mineral. In the investigated samples vanadium concentration in magnetite ranges from 0.12 to 0.32% V2O3 with higher concentrations in the southern part of the deposit. No such conclusions regarding spatial distribution could be done for titanium. Furthermore, the investigations indicated that alteration from primary magnetite to secondary hematite does not significantly affect the trace element chemistry of the minerals. Titanium in iron oxides occurs as either inclusions or lamellae of titanium oxide minerals. Vanadium in iron oxides occur as a substitution element and does not occur in stochiometric vanadium minerals. It is considered unfeasible to lower the content of these deleterious elements by physical separation methods. / Leveäniemi är en järnoxid-apatitfyndighet (IOA) i Norrbotten som bryts av LKAB. Fyndigheten har en delvis mer komplex mineralogi än de närliggande och mer kända IOA-fyndigheterna Kiirunavaara och Malmberget. Leveäniemifyndigheten innehåller jämförelsevis mer malm innehållande både magnetit och hematit men även maghemit samt med något annorlunda spårämneskemi i järnoxidmineralen. Hematit anses inte i nuläget vara ett värdemineral i Svappavaaras malmförädling och i magnetitekoncentratet anses titan och vanadin utgöra straffelement. Malmprov togs från utvalda borrkärnor och från dessa tillverkades polerade tunnslip som undersöktes med optisk mikroskopering, EPMA och FE-SEM-EDS. Undersökningarna var fokuserade på järnoxidernas mineralogi och mineralkemi med speciellt fokus på titan och vanadin då grundämnena anses vara skadliga i efterföljande masugns- eller direktreduktionsprocesser. Undersökningarna visade att magnetit är det dominerade mineralet med sekundär hematit som det näst vanligaste förekommande järnoxidsmineralet. I de undersökta proven varierade vanadinhalten från 0,12% till 0,32% V2O3 med högre halter i fyndigheten södra delar. Inga liknande slutsatser angående rumsliga fördelningen av titan kunde göras. Vidare så indikerade undersökningarna att omvandling från primär magnetit till sekundär hematit inte nämnvärt påverkar spårämneskemin i mineralen. Titan i järnoxider förekommer antingen som inneslutning eller lameller av titanoxidsmineral. Vanadin i järnoxider förekommer som ett substitutionselement och förekommer inte som stökiometriska vanadinmineral. Det anses inte vara tekniskt eller ekonomiskt möjligt att sänka halterna av dessa skadliga grundämnen med hjälp av fysiska separationsmetoder.

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Pancreatic ductal adenocarcinoma (PDAC) is one of the most difficult type of cancer to treat, due to late diagnosis which is a result of vague symptoms and lack of biomarkers, as well as refractory behavior toward current treatment protocols. Imaging of the disease progression therefore plays a crucial role in identifying potentially curable PDAC patients at an early stage. Nanoparticle-based contrast agents have shown multimodal capabilities and potential to enhance the contrast of previously undetectable pathological changes, including PDAC. In this master’s thesis study, an iron oxide nanoparticle (IONP) was evaluated as a potential multimodal contrast agent for both photoacoustic imaging (PAI) and magnetic resonance imaging (MRI). The investigated particle was composed of Fe3O4 with a hydrodynamic size of 418.5 nm and a zeta potential of -27.7 mV. In the agarose suspended IONP phantom studies, the IONP demonstrated a two-fold higher T2 contrast compared to commercial IONP VivoTrax (Magnetic Insight), as well as generating strong and stable photoacoustic signal throughout the first near-infrared window (700 to 1000 nm). Based on this thesis’ proof of concept study, Fe3O4 IONP showed good potential as multimodal contrast agent for MRI and PAI. Future work consists of modification of the particle composition and in vivo imaging on animals to evaluate the application in PDAC diagnostics.

The aim of this study was to compare the barrier properties of organic coatings with the same polymer matrix but different types of iron oxide particles, commercial and recycled. The work was carried out for the company SSAB with the aim of investigating whether the pigment Merox ferric oxide, which is produced in-house at the company during the pickling process, can be used and replace commercial iron oxide pigment. Evaluation of the barrier properties was done using electrochemical impedance spectroscopy where the capacitance of the coatings is calculated and reflects the water absorption of the coating over a period of exposure to the electrolyte. By comparing the capacitance of the different coatings, an estimation of the water transport through the different coatings was made. Complementary methods used were digital optical microscopy and scanning electron microscopy.  In this project, 6 lab samples were evaluated. In common, the samples consisted of the same metal substrate, hot-dip galvanized steel, and the binder in the coatings was polyester-melamine. Sample 1 consisted of the binder only, sample 2 contained the commercial iron oxide pigment, samples 3 and 4 consisted of Merox pigments but different levels of chlorine in the pigment. The thickness of the coatings of the 4 samples was 6 m. Sample 5 had a thicker coating of 20 m and contained Merox pigment. The last sample evaluated was a reference sample with anti-corrosive pigment with a thickness of 20 m. Furthermore, exposure tests were carried out with sample 5 to test how different electrolyte solutions affected the samples. The electrolytes tested were 1 M Na2SO4 (for reference), 1 M NaNO3 and 0.1 M NaCl.  The impedance measurements were performed in 3 parallel measurements on the samples with thinner coating (6 m) and an average of the capacitance was used to analyze how the capacitance changes over time. The results showed that sample 1 had much better barrier properties than the samples containing iron oxide pigments, although the exposure time to electrolyte was longer for this sample, the capacitance was lower. Both samples 2 and 4 increased rapidly in capacitance over a short period of time. Sample 3 had a rapid increase at the beginning which later decreased, the sample showed better barrier properties compared to samples 2 and 4. Cross-sectional studies carried out by scanning electron microscopy detected corrosion formation between the zinc and the coating on all samples with thinner coatings. Only one impedance measurement was made on samples 5 and 6, hence multiple measurements need to be performed to calculate the capacitance over time and provide complete and reliable results for these samples.  The results of the exposure tests indicated that the electrolyte used for the electrochemical impedance measurements, 1 M Na2SO4 is more corrosive than the other electrolytes tested, 1 M NaNO3 and 0.1 M NaCl. / Syftet med denna studie var att jämföra barriärsegenskaper hos organiska beläggningar med samma polymer matris men olika typer av järnoxidpartiklar, kommersiella och återvunna. Arbetet utfördes åt företaget SSAB med målet att undersöka om pigmentet Merox ferric oxide, vilket produceras internt på företaget under betningsprocessen, kan användas och ersätta kommersiellt järnoxidpigment. Utvärdering av barriärsegenskaperna gjordes med elektrokemisk impedansspektroskopi där beläggningarnas kapacitans beräknas och avspeglar vattenabsorption av beläggningen över en tidsperiod av exponering till elektrolyt. Genom att jämföra kapacitansen för de olika beläggningarna, har en estimering av vattentransporten genom de olika beläggningarna gjorts. Kompletterande metoder som användes var digitalt optiskt mikroskop och svepelektronmikroskopi.  I detta projekt utvärderades 6 labb-prover. Gemensamt bestod proverna av samma metallsubstrat, varmförzinkat stål och bindaren i beläggningarna var polyester-melamine. Prov 1 bestod endast av bindaren, prov 2 innehöll kommersiellt järnoxidpigmentet. Prov 3 och 4 bestod av Merox pigment men olika halter av klor i pigmentet. Tjockleken på beläggningarna hos de 4 proverna var 6 m. Prov 5 hade en tjockare beläggning på 20 m och innehöll Merox pigment. Det sista provet som utvärderades var ett referensprov med anti-korrosivt pigment med en tjocklek på 20 m. Vidare gjordes exponeringstester med prov 5 för att testa hur olika elektrolytlösningar påverkade proverna. Elektrolyterna som testades var 1 M Na2SO4 (som referens), 1 M NaNO3 och 0,1 M NaCl.  Impendansmätningarna utfördes i 3 parallella mätningar på proverna med tunnare beläggning (6 m) och ett medelvärde av kapacitansen användes för att analysera hur kapacitansen förändras över tiden. Resultatet visade att prov 1 hade mycket bättre barriärsegenskaper än proverna som innehöll järnoxid pigment, även fast exponeringstiden gentemot elektrolyt var längre för detta prov så var kapacitansen lägre. Både prov 2 och 4 ökade snabbt i kapacitans under en kort tidsperiod. Prov 3 hade en snabb ökning i början som senare avtog, provet visade bättre barriärsegenskaper jämfört med prov 2 och 4. Tvärsnittsstudier som genomfördes med svepelektronmikroskopi detekterade korrosionsbildning mellan zink och beläggningen på alla prover med tunnare beläggning. Endast en impedansmätning på prov 5 och 6 utfördes, därav behövs flera mätningar genomföras för att kunna beräkna kapacitansen över tid och ge fullständiga och pålitliga resultat för dessa prover.  Resultaten från exponeringstesterna visade på att elektrolyten som använts för elektrokemiska impedansmätningarna, 1 M Na2SO4 är mer korrosiv än de andra elektrolyterna som testades, 1 M NaNO3 och 0,1 M NaCl.

No / A major drawback with current cancer therapy is the prevalence of unrequired doselimiting toxicity to non-cancerous tissues and organs, which is further compounded by a limited ability to rapidly and easily monitor drug delivery, pharmacodynamics and therapeutic response. In this report, the design and characterization of novel multifunctional “theranostic” nanoparticles (TNPs) is described for enzyme-specifi c drug activation at tumor sites and simultaneous in vivo magnetic resonance imaging (MRI) of drug delivery. TNPs are synthesized by conjugation of FDA-approved iron oxide nanoparticles ferumoxytol to an MMP-activatable peptide conjugate of azademethylcolchicine (ICT), creating CLIOICTs (TNPs). Signifi cant cell death is observed in TNP-treated MMP-14 positive MMTVPyMT breast cancer cells in vitro, but not MMP-14 negative fi broblasts or cells treated with ferumoxytol alone. Intravenous administration of TNPs to MMTV-PyMT tumor-bearing mice and subsequent MRI demonstrates signifi cant tumor selective accumulation of the TNP, an observation confi rmed by histopathology. Treatment with CLIO-ICTs induces a significant antitumor effect and tumor necrosis, a response not observed with ferumoxytol. Furthermore, no toxicity or cell death is observed in normal tissues following treatment with CLIO-ICTs, ICT, or ferumoxytol. These fi ndings demonstrate proof of concept for a new nanotemplate that integrates tumor specifi city, drug delivery and in vivo imaging into a single TNP entity through attachment of enzyme-activated prodrugs onto magnetic nanoparticles. This novel approach holds the potential to signifi cantly improve targeted cancer therapies, and ultimately enable personalized therapy regimens. / Yorkshire Cancer Research

Yes / The gadolinium-doped iron oxide nanoparticles (GdIONP) with greater specific power adsorption rate (SAR) than Fe3O4 was developed and its potential application in tumour therapy and particle tracking were demonstrated in transgenic adenocarcinoma of the mouse prostate C1 (TRAMP-C1) tumours. The GdIONPs accumulated in tumour region during the treatment could be clearly tracked and quantified by T2-weighted MR imaging. The therapeutic effects of GdIONP-mediated hyperthermia alone or in combination with radiotherapy (RT) were also evaluated. A significant increase in the tumour growth time was observed following the treatment of thermotherapy (TT) only group (2.5 days), radiation therapy only group (4.5 days), and the combined radio-thermotherapy group (10 days). Immunohistochemical staining revealed a reduced hypoxia region with vascular disruption and extensive tumour necrosis following the combined radio-thermotherapy. These results indicate that GdIONP-mediated hyperthermia can improve the efficacy of RT by its dual functions in high temperature (temperature greater than 45 °C)-mediated thermal ablation and mild-temperature hyperthermia (MTH) (temperature between 39 and 42 °C)-mediated reoxygenation.