Distance measurements in Au nanoparticles functionalized with nitroxide radicals and Gd3+ -DTPA chelate complexes

TY - JOUR

T1 - Distance measurements in Au nanoparticles functionalized with nitroxide radicals and Gd3+ -DTPA chelate complexes

AU - Yulikov, M.

AU - Lueders, P.

AU - Farooq Warsi, M.

AU - Chechik, V.

AU - Jeschke, G.

PY - 2012/8

Y1 - 2012/8

N2 - Nanosized gold particles were functionalised with two types of paramagnetic surface tags, one having a nitroxide radical and the other one carrying a DTPA complex loaded with Gd . Selective measurements of nitroxide-nitroxide, Gd -nitroxide and Gd -Gd distances were performed on this system and information on the distance distribution in the three types of spin pairs was obtained. A numerical analysis of the dipolar frequency distributions is presented for Gd centres with moderate magnitudes of zero-field splitting, in the range of detection frequencies and resonance fields where the high-field approximation is only roughly valid. The dipolar frequency analysis confirms the applicability of DEER for distance measurements in such complexes and gives an estimate for the magnitudes of possible systematic errors due to the non-ideality of the measurement of the dipole-dipole interaction.

AB - Nanosized gold particles were functionalised with two types of paramagnetic surface tags, one having a nitroxide radical and the other one carrying a DTPA complex loaded with Gd . Selective measurements of nitroxide-nitroxide, Gd -nitroxide and Gd -Gd distances were performed on this system and information on the distance distribution in the three types of spin pairs was obtained. A numerical analysis of the dipolar frequency distributions is presented for Gd centres with moderate magnitudes of zero-field splitting, in the range of detection frequencies and resonance fields where the high-field approximation is only roughly valid. The dipolar frequency analysis confirms the applicability of DEER for distance measurements in such complexes and gives an estimate for the magnitudes of possible systematic errors due to the non-ideality of the measurement of the dipole-dipole interaction.

UR - http://www.scopus.com/inward/record.url?scp=84863959223&partnerID=8YFLogxK

U2 - 10.1039/c2cp40282c

DO - 10.1039/c2cp40282c

M3 - Article

AN - SCOPUS:84863959223

SN - 1463-9076

VL - 14

SP - 10732

EP - 10746

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

IS - 30

ER -