title: ESR micro-imaging of LiNc-BuO crystals in PDMS: spatial and spectral grain distribution.
abstract: Microcrystals of lithium octa-n-butoxynaphthalocyanine (LiNc-BuO) in a bio-compatible and oxygen-permeable polymer matrix of poly-dimethyl-siloxane (PDMS) can be used for repetitive non-invasive imaging of oxygen in live specimens by means of mm-scale electron spin resonance (ESR) imaging. This probe denoted as "oxychip" was characterized by high-resolution mum-scale ESR microcopy to reveal the fine details of its spatial and spectral properties. The ESR micro-images of a typical oxychip device showed that while the spatial distribution of the microcrystals in the polymer is fairly homogenous (as revealed by optical microscopy), the ESR signal originates only from a very few dominant crystals. Furthermore, spectral-spatial analysis in a microcrystal and a sub-microcrystal spatial resolution reveals that each crystal has a slightly different g-factor and also exhibits variations in linewidth, possibly due to the slightly different individual crystallization process.
authors.affiliation: Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Haifa 32000, Israel. ab359@tx.technion.ac.il
authors.forename: Aharon
authors.initials: A
authors.lastname: Blank
authors.forename: Revital
authors.initials: R
authors.lastname: Halevy
authors.forename: Michael
authors.initials: M
authors.lastname: Shklyar
authors.forename: Lazar
authors.initials: L
authors.lastname: Shtirberg
authors.forename: Periannan
authors.initials: P
authors.lastname: Kuppusamy
mesh_terms: D000465:Algorithms; D003461:Crystallography / Q000379:methods*; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D008665:Metalloporphyrins / Q000737:chemistry*; D008838:Microcomputers; D012984:Software
chemical_list: D004129:Dimethylpolysiloxanes; D008665:Metalloporphyrins; C481390:lithium 5,9,14,18,23,27,32,36-octa-n-butoxy-2,3-naphthocyanine; C013830:baysilon