Electrodeposited Fe and Fe-Au nanowires were studied for potential as MRI contrast agents, especially for T-weighted imaging. Transverse relaxivities up to r = 77.1 mM Fe s (at 1.5 T) were achieved when Fe-Au nanowires were coated with thiol and carboxylic acid functionalized poly(ethyleneglycol). T-Weighted images (9 T) verified successful contrast.

Isolating tumor exosomes (TEX) secreted by cancer cells can provide valuable information about the state of a tumor. Here, we present a method to rapidly isolate TEX using magnetic nanowires (MNWs). Specifically, two sets of Fe/Au segmented MNWs were used to isolate TEX released by canine osteosarcoma cell lines (OSCA 8,32,and 40). These MNWs were prepared by electrodeposition showcasing similar length (2.2(1) μm) and diameter (36(3) nm) but different Fe/Au segment thickness: 120(20)/30( 6) nm (sample A) and 28(7)/3(1) nm (sample B).Magnetic measurements indicate that we can effectively tune the magnetic response of the MNWs by changing their segment thickness, obtaining a more anisotropic behavior for sample A. The internalization of these MNWs by OSCA cells as a function of their concentration has been followed by fluorescence microscopy, and a concentration around 25 μg of Fe/Au MNWs per 3 × 10 5 cells has been defined as optimal. Electron microscopy images have revealed that, once internalized, these MNWs end up residing within lysosomes inside the cancer cells, where they tend to be degraded (especially the Fe segments) and fragmented into smaller pieces. Lower degradation for sample B has been observed and related to differences in the synthesis/functionalization process of both samples. We have hypothesized that these fragments of Fe/ Au MNWs are packaged into TEX released to the medium which can then be isolated via a magnetic stand. This has been tested by carrying out TEX isolation experiments on the OSCA cell and comparing the magnetically isolated TEX with those isolated by using conventional methods based on centrifugation. Nanoparticle tracking analysis (NanoSight) has confirmed that the TEX isolated with MNWs have a comparable size distribution and yield to those obtained by using conventional methods, indicating that our magnetic isolation method can consistently provide relatively high TEX yields in a low-cost and fast way.

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2016) Optimized magneto-optical isolator designs inspired by seedlayer-free terbium iron garnets with opposite chirality. ACS Photonics, 3(10), pp. 1818Photonics, 3(10), pp. -1825Photonics, 3(10), pp. . (doi:10.1021 This is the author's final accepted version.There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it.http://eprints.gla.ac.uk/124482/ ∥ School of Engineering, University of Glasgow, Glasgow, Scotland, U.K. ABSTRACT: ABSTRACT: ABSTRACT:ABSTRACT: Simulations demonstrate that undoped yttrium iron garnet (YIG) seedlayers cause reduced Faraday rotation in silicon-oninsulator (SOI) waveguides with Ce-doped YIG claddings. Undoped seedlayers are required for the crystallization of the magneto-optical Ce:YIG claddings, but they diminish the interaction of the Ce:YIG with the guided modes. Therefore new magneto-optical garnets, terbium iron garnet (TIG) and bismuth-doped TIG (Bi:TIG), are introduced that can be integrated directly on Si and quartz substrates without seedlayers. The Faraday rotations of TIG and Bi:TIG films at 1550nm were measured to be +500 and -500°/cm, respectively. Simulations show that these new garnets have the potential to significantly mitigate the negative impact of the seedlayers under Ce:YIG claddings. The successful growth of TIG and Bi:TIG on low-index fused quartz inspired novel garnet-core waveguide isolator designs, simulated using finite difference time domain (FDTD) methods. These designs use alternating segments of positive and negative Faraday rotation for push-pull quasi phase matching in order to overcome birefringence in waveguides with rectangular cross-sections. KEYWORDS KEYWORDS KEYWORDS KEYWORDS: yttrium iron garnet (YIG) seedlayer, terbium iron garnet (TIG), cerium doped yttrium iron garnet (Ce:YIG) , silicon on insulator (SOI) waveguides, Faraday rotation, optical isolator Photonic systems have ever increasing applications in high-speed electronics/ spintronics 1,2 , computing 3 , telecommunications 4,5 and medicine 6 . These systems use light as the signal carrier, and similar to diodes in electronics, photonic systems require non-reciprocal devices with high optical isolation capabilities to protect light sources. Currently, non-reciprocal photonic materials are only available in discrete components. However, if light sources are to be integrated onto photonic chips, non-reciprocal devices will also be needed on those chips. Indeed, isolators will be necessary anywhere in optical circuits where back-reflections are detrimental and likely to occur. Garnets, with their unique magneto-optical (MO) properties have been the material of choice for building passive non-reciprocal devices [7][8][9][10] . In general, non-garnet non-reciprocal devices are active devices that require external power sources, which increase the complexity and cost of the device [11][12][13][14] . MO effects in garnets are the result of non-zero off-diagonal components in the dielectric matrix (ε) ...