Photolithographic production of glass sample holders for improved sensitivity and resolution in ESR microscopy

Halevy, Revital; Talmon, Y.; Blank, Aharon

doi:10.1007/bf03166604

Cited by 9 publications

(6 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sample preparation for micro-imaging involved slicing a larger piece of PTM-TE:PDMS using a sharp scalpel to approximately 100-μm slices, which were further cut to a shape of an equilateral triangle with a side dimension of ~ 500 μm, to fit into the imaging probe of the microscope. Samples were made anoxic by sealing them in a specially-prepared glass sample holder under argon atmosphere (Halevy et al 2007). A 2-D spatial 1-D spectral image of the prepared sample was acquired using the following parameters: 128 spatial projections × 32 spectral projections (total of 4096 projections); 128 points per projection; time constant, 0.1 s; modulation amplitude, 0.27 G; maximum gradient magnitude of 4.9 T/m for the X-axis and 4.5 T/m for the Y-axis; microwave frequency, 15.46 GHz.…”

Section: Methodsmentioning

confidence: 99%

A molecular paramagnetic spin-doped biopolymeric oxygen sensor

Meenakshisundaram¹,

Eteshola²,

Blank³

et al. 2010

Biosensors and Bioelectronics

View full text Add to dashboard Cite

Electron paramagnetic resonance (EPR) oximetry is a powerful technique capable of providing accurate, reliable, and repeated measurements of tissue oxygenation, which is crucial to the diagnosis and treatment of several pathophysiological conditions. Measurement of tissue pO 2 by EPR involves the use of paramagnetic, oxygen-sensitive probes, which can be either soluble (molecular) in nature or insoluble paramagnetic materials. Development of innovative strategies to enhance the biocompatibility and in vivo application of these oxygen-sensing probes is crucial to the growth and clinical applicability of EPR oximetry. Recent research efforts have aimed at encapsulating particulate probes in bioinert polymers for the development of biocompatible EPR probes. In this study, we have developed novel EPR oximetry probes, called PTM-TE:PDMS chips, by dissolving and incorporating the soluble (molecular) EPR probe, perchlorotriphenylmethyl triester (PTM-TE), in an oxygen-permeable polymer matrix, polydimethyl siloxane (PDMS). We demonstrate that such incorporation (doping) of PTM-TE in PDMS enhanced its oxygen sensitivity several fold. The castmolding method of fabricating chips enabled them to be made with increasing amounts of PTM-TE (spin density). Characterization of the spin distribution within the PDMS matrix, using EPR microimaging, revealed potential inhomogeneties, albeit with no adverse effect on the oxygen-sensing characteristics of PTM-TE:PDMS. The chips were resistant to autoclaving or in vitro oxidoreductant treatment, thus exhibiting excellent in vitro biostability. Our results establish PTM-TE:PDMS as a viable probe for biological oxygen-sensing, and also validate the incorporation of soluble probes in polymer matrices as an innovative approach to the development of novel probes for EPR oximetry.

show abstract

Section: Methodsmentioning

confidence: 99%

A molecular paramagnetic spin-doped biopolymeric oxygen sensor

Meenakshisundaram¹,

Eteshola²,

Blank³

et al. 2010

Biosensors and Bioelectronics

View full text Add to dashboard Cite

show abstract

“…7B). 15 The unique design of the sample holder provides well‐defined patterns for the imaging experiments and contributes to the enhancement in the sensitivity of the pulsed ESR imaging system. The sample contained approximately ∼10 11 spins (evaluated by the CW ESR signal vs. reference signal of Trityl 1 m̈M solution).…”

Section: Methodsmentioning

confidence: 99%

High‐Resolution ESR Imaging of N@C₆₀ Radicals on a Surface

Suhovoy

Blank

2008

Israel Journal of Chemistry

View full text Add to dashboard Cite

Electron Spin Resonance Microcopy (ESRM) is an imaging method capable of observing stable free radicals in small samples with a spatial resolution of ∼1 micron. Currently this technique is pursued mainly for biological applications at room temperature and at relatively low static magnetic fields. Future progress, which involves the use of higher magnetic fields at cryogenic temperatures, could significantly improve sensitivity and resolution and thus make this method attractive to many solid‐state and physical science applications. Here we consider a possible application of ESRM to the field of quantum computing employing Endohedral Nitrogen fullerene (N@C60) molecules. In order to fully address the challenges of quantum computing, the resolution should be significantly improved to ∼10 nm and the sensitivity should approach the single spin level. In the present work we show some preliminary results conducted with diluted N@C60 samples. A 2D image of N@C60 dispersed on a surface was obtained at a field of ∼0.6 T and at room temperature. Under these conditions the current sensitivity of the ESRM system is around 107−108 spins, and due to the low enrichment factor of the N@C60 sample (∼10−6), we were able to reach image resolution of only ∼50 m̈m. Future steps that are taken in order to significantly improve resolution and sensitivity of the system are discussed. These include the use of highly concentrated samples to be measured at ∼4 K and at a field of more than 1 T, which would lead to a resolution of ∼100 nm and a sensitivity of ∼100 spins.

show abstract

“…6), produced by a photolithography process [44]. This cover prevents the sample from dehydrating and can be used to isolate it from the outside environment.…”

Section: Sample Holdersmentioning

confidence: 99%