spinflex offers solutions that are an ideal addition to the field of biological research. They enable you, for example, to obtain a deeper understanding of protein structures, observe the dynamic of biomolecules, and monitor cells in-vivo. spinflex offers powerful analytical tools with very a “user friendly” software application. spinflex products can meet your needs in the various aspects of biology, such as:

publications employing spinflex products

New approach to measuring oxygen diffusion and consumption in encapsulated living cells

(Acta Biomaterialia 101, (2020), 384)

Cell microencapsulation within biocompatible polymers is an established technology for immobilizing living cells that secrete therapeutic products. These can be transplanted into a desired site in the body for the controlled and continuous delivery of the therapeutic molecules. One of the most important properties of the material that makes up the microcapsule is its oxygen penetrability, which is critical for the cells’ survival.

Oxygen reaches the cells inside the microcapsules via a diffusion process. The diffusion coefficient for the microcapsules’ gel material is commonly measured using bulk techniques, where the gel in a chamber is first flushed with nitrogen and the subsequent rate of oxygen diffusion back into it is measured by an oxygen electrode placed in the chamber.

The research  develop and demonstrate a proof of principle for a new approach to measuring and imaging the partial pressure of oxygen (pO2) inside a single microcapsule by means of high-resolution and high-sensitivity electron spin resonance (ESR). The new ESR approach was used to measure the O2 diffusion properties of two types of gel materials (alginate and extracellular matrix – ECM), as well as to map a 3D image of the oxygen inside single microcapsules with living cells.

Electron Spin Resonance Microscopic Imaging of Oxygen Concentration in Cancer Spheroids

(Journal of Magnetic Resonance – 256, (2015), 78)

Oxygen (O2) plays a central role in most living organisms. The concentration of O2 is important in physiology and pathology. Despite the importance of accurate knowledge of the O2 levels, there is very limited capability to measure with high spatial resolution its distribution in millimeter-scale live biological samples. Many of the current oximetric methods, such as oxygen microelectrodes and fluorescence lifetime imaging, are compromised by O2 consumption, sample destruction, invasiveness, and difficulty to calibrate. Here, we present a new method, based on the use of the pulsed electron spin resonance (ESR) microimaging technique to obtain a 3D mapping of oxygen concentration in millimeter-scale biological samples. ESR imaging requires the incorporation of a suitable stable and inert paramagnetic spin probe into the desirable object. In this work, we use microcrystals of a paramagnetic spin probe in a new crystallographic packing form (denoted tg-LiNc-BuO). These paramagnetic species interact with paramagnetic oxygen molecules, causing a spectral line broadening that is linearly proportional to the oxygen concentration. Typical ESR results include 4D spatial-spectral images that give an indication about the oxygen concentration in different regions of the sample. This new oximetry microimaging method addresses all the problems mentioned above. It is noninvasive, sensitive to physiological oxygen levels, and easy to calibrate. Furthermore, in principle, it can be used for repetitive measurements without causing cell damage. High resolution 3D oxygen maps could make it possible to evaluate the relationship between morphological and physiological alterations in the spheroids, which would help understand the oxygen metabolism in solid tumors and its correlation with the susceptibility of tumors to various oncologic treatments.

Additional Publications

Induction-detection electron spin resonance with spin sensitivity of a few tens of spinsAuthors name:
Yaron Artzi, Ygal Twig

ppl. Phys. Lett. 106, (2015), 084104

Transcutaneous oxygen measurement in humans using a paramagnetic skin adhesive film

Authors name:
Maciej M. Kmiec, Huagang Hou

Magnetic Resonance in Medicine 81, (2019), 781 – 794

Surface loop-gap resonators for electron spin resonance at W-band

Authors name:
Yagel Twig, David Cristea

Review of Scientific Instruments 88, (2017), 123901