Stationary and high-frequency pulsed electron paramagnetic resonance of a calcified atherosclerotic plaque

Radiation-Induced Stable Radicals in Calcium Phosphates: Results of Multifrequency EPR, EDNMR, ESEEM, and ENDOR Studies

“…One of the analytical, non-destructive tools for the investigation of CPs of both biogenic and synthetic origins is electron paramagnetic resonance (EPR) [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]. The increased sensitivity, spectral and temporal resolution, along with the improved stability of modern commercial EPR spectrometers has opened new possibilities in the study of CPs during the last decade, taking a step towards in situ EPR imaging (EPRI) [44].…”

Paramagnetic Manganese in the Atherosclerotic Plaque of Carotid Arteries

“…Figure 1). Their possible origin, correlation between the degree of calcification, spectral and relaxation parameters of FR, and the radiation-induced FR are discussed in [6] and are not in the focus of the present research.…”

“…The arrow shows the value of the magnetic field B rel in which the T 2e curves (ESE decays) were measured. Solid line indicates the presence of additional paramagnetic species (mainly, carbon-centered “free” radicals, FR [6]).…”

“…It is logical to assume that the status of the AP organomineral matrix should (or may) mirror the status of the AP stability but different aspects of calcifications must be taken into account to establish a significant relationship with the AP progress. These include chemical diversity, morphologic features at the mesoscopic and macroscopic scale, location, presence of trace elements, presence of molecular groups, such as carbonate groups in apatites [6, 8]. It, in its turn, implies the comprehensive analysis of the clinical and reference materials by the variety of the analytical methods, some of which are still not widely implemented not only into the clinical practice but even into the advanced biochemical research.…”

“…In a series of our previous papers [17–21], we mainly focused on the investigation of the natural and synthetic nano- and micropowders of HAp with the substitution by different ions and groups (lead, manganese, carbonates, nitrogen containing species) in the large concentration range of 0.001–14.0 wt% as well as on the comparison of the results acquired on the model systems with those obtained from the postmortem clinical material [6, 7]. We have gathered the experience of the characterization of HAp and AP samples by different EPR techniques to choose the more sensitive high-field (HF) EPR (W-band, magnetic field B 0 of about 3.4 T) which requires the substance grain size with the cross-sectional diameter of less than 1 mm.…”