TY  - JOUR
AU  - Tircsó, Gyula
AU  - Brücher, Ernő
AU  - Baranyai, Zsolt
AU  - Kálmán, Ferenc Krisztián
AU  - Tóth, Imre
TI  - Nyíltláncú és makrociklusos aminokarboxilát ligandumok szintézise és fémkomplexeik vizsgálata. koordinációs kémia az orvosi képalkotás szolgálatában
TS  - koordinációs kémia az orvosi képalkotás szolgálatában
JF  - MAGYAR KÉMIAI FOLYÓIRAT - KÉMIAI KÖZLEMÉNYEK (1997-)
J2  - MAGY KÉM FOLY KÉM KÖZL
VL  - 123
PY  - 2017
IS  - 2
SP  - 82
EP  - 93
PG  - 12
SN  - 1418-9933
DO  - 10.24100/MKF.2017.02.82
UR  - https://m2.mtmt.hu/api/publication/3241815
ID  - 3241815
N1  - Synthesis  of  Linear  and  Macrocyclic  Aminopolycarboxylate  Ligands  and  Chemical  Characterization  of  their  MetalComplexes for Safe Use in Medical Imaging
LA  - Hungarian
DB  - MTMT
ER  - 

TY  - JOUR
AU  - Micskei, Károly Endre
AU  - HELM, L
AU  - Brücher, Ernő
AU  - MERBACH, AE
TI  - O-17 NMR-STUDY OF WATER EXCHANGE ON [GD(DTPA)(H2O)]2- AND [GD(DOTA)(H2O)]- RELATED TO NMR IMAGING
JF  - INORGANIC CHEMISTRY
J2  - INORG CHEM
VL  - 32
PY  - 1993
IS  - 18
SP  - 3844
EP  - 3850
PG  - 7
SN  - 0020-1669
DO  - 10.1021/ic00070a013
UR  - https://m2.mtmt.hu/api/publication/1378688
ID  - 1378688
AB  - The water-exchange rate constants for the [Gd(DTPA)(H2O)]2- and [Gd(DOTA)(H2O)]-complexes as determined by variable-temperature O-17 NMR are respectively k(ex)298 = (4.1 +/- 0.3) X 10(6) and (4.8 +/- 0.4) X 10(6) s-1. The activation volumes (DELTAV(double dagger)), measured up to 200 MPa, are 12.5 +/- 0.2 and 10.5 +/- 0.2 cm3 mol-1, indicating an extreme dissociative activation mode for the water-exchange mechanism. The mechanism (D) is further supported by the large activation enthalpies (DELTAH(double dagger) = +52.0 +/- 1.4 and +48.8 +/- 1.6 kJ mol-1) and positive entropies (DELTAS(double dagger) = +56.2 +/- 5 and +46.6 +/- 6 kJ mol-1 K-1) obtained for the [Gd(DTPA)(H2O)]2- and [Gd(DOTA)(H2O)]- complexes, respectively. In the first coordination sphere of these two monoaqua complexes there is only space for one water molecule, and thus the bond breaking of the coordinated water should be the rate-determining step. The O-17 relaxation contribution of the second coordination sphere was estimated by investigating [Gd(TETA)]-, which has no water in the first coordination sphere. All these considerations lead to the conclusion that the effectiveness of [Gd(DTPA)(H2O)]2- and [Gd(DOTA)(H2O)]- as contrast agents in MRI is not limited by the relatively low water-exchange rates but by T1m, the longitudinal relaxation time of water protons in the first coordination sphere.
LA  - English
DB  - MTMT
ER  -