Synthetic polymers as biomacromolecular models for studying ligand–protein interactions: A nuclear spin relaxation approach

1H and 19F NMR relaxation studies of fleroxacin with Micrococcus luteus

“…Various methods such as chemical shift differences [14][15][16], line width analysis, relaxation measurements, determination of diffusion coefficients [17] and intermolecular magnetization transfer techniques such as tr-NOE [18,19] or WaterLOGSY experiments [20] have been reported. There are a number of studies based on relaxation measurements for determination of ligand-macromolecule binding [21][22][23][24][25][26]. Both longitudinal (T 1 ) and transverse (T 2 ) relaxation times are dependent on the dipolar interaction between a macromolecule and a substrate.…”

NMR Investigation of the Interaction of Three Non-Steroidal Anti-Inflammatory Drugs with Human Serum Albumin

“…As a consequence of the interaction, the drug goes from the fast motion region (ω 2 τ c 2 « 0.6; ω = Larmor frequency), characteristics of small molecules in their free state, to the slow-motion region (ω 2 τ c 2 » 0.6) where macromolecules and their complexes are found. The non-selective relaxation parameter R 1 ns increases with the increase in ω 2 τ c 2 up to 0.6, and then it reaches a maximum and starts decreasing (Equation (A2)); on the contrary, the function R 1 ms has a point of flex in correspondence of 0.6, and then keeps increasing with increasing of ω 2 τ c 2 (Equation (A3)) [ 25 , 26 , 27 ]. This high sensitivity to the change of motion regime explains why R 1 ms is usually preferred for investigations requiring a strong excess of drug with respect to the macromolecule [ 28 ].…”

Estudos estruturais e de interação de novos inibidores e ativadores da tirosinase

“…Outro parâmetro de RMN que pode ser utilizado nos estudos de interação alvo-ligante é o tempo de relaxação (Corbini, 2006;Figueroa-Villar, 2009;Luo, 1999;Ludwig, 2009). Relaxação é um processo que corresponde ao retorno de um sistema para o estado de equilíbrio após uma perturbação.…”