TY - JOUR

T1 - Epr Spectroscopy of Adsorbed Spin-Labeled Peptides

T2 - Immobilization of Trichogin on the Titanium Oxide

AU - Samoilova, R. I.

AU - Syryamina, V. N.

AU - Tsvetkov, Yu D.

AU - Dzuba, S. A.

AU - Toniolo, C.

AU - Formaggio, F.

PY - 2018/11/1

Y1 - 2018/11/1

N2 - The TOAC-spin-labeled peptide Trichogin GA IV adsorbed on the TiO2 surface is studied. It is shown that the continuous wave (CW) electron paramagnetic resonance (EPR) spectrum does not depend on temperature in a wide range of 77–300 K. A pulsed EPR method of electron spin echo (ESE) utilizing a two-pulse sequence (π/2-τ-π) is used to study temperature dependence of the phase relaxation time, TF. The TF values are found to change from 750 ns to 100 ns in the interval of 77–300 K. The pulsed electronelectron double resonance (PELDOR) measurements utilizing the pulse sequence((π/2)A,-T-πB,-(τ-T)-πA) show that the space distribution of spin labels on the surface remains uniform irrespective of the temperature, and provide the fractal dimension of the surface of 2.7±0.1. The obtained results testify that EPR pulse experiments can be used to study adsorbed spin-labeled molecules at room temperatures, i.e. not only at cryogenic temperatures.

AB - The TOAC-spin-labeled peptide Trichogin GA IV adsorbed on the TiO2 surface is studied. It is shown that the continuous wave (CW) electron paramagnetic resonance (EPR) spectrum does not depend on temperature in a wide range of 77–300 K. A pulsed EPR method of electron spin echo (ESE) utilizing a two-pulse sequence (π/2-τ-π) is used to study temperature dependence of the phase relaxation time, TF. The TF values are found to change from 750 ns to 100 ns in the interval of 77–300 K. The pulsed electronelectron double resonance (PELDOR) measurements utilizing the pulse sequence((π/2)A,-T-πB,-(τ-T)-πA) show that the space distribution of spin labels on the surface remains uniform irrespective of the temperature, and provide the fractal dimension of the surface of 2.7±0.1. The obtained results testify that EPR pulse experiments can be used to study adsorbed spin-labeled molecules at room temperatures, i.e. not only at cryogenic temperatures.

KW - EPR spectroscopy

KW - immobilization of titanium oxide

KW - spin-labeled peptide

KW - C spin-labeled peptide

KW - PELDOR

UR - http://www.scopus.com/inward/record.url?scp=85058489700&partnerID=8YFLogxK

U2 - 10.1134/S0022476618060070

DO - 10.1134/S0022476618060070

M3 - Article

AN - SCOPUS:85058489700

VL - 59

SP - 1299

EP - 1301

JO - Journal of Structural Chemistry

JF - Journal of Structural Chemistry

SN - 0022-4766

IS - 6

ER -