A closer look at the mode of binding of drug pemetrexed with CT-DNA

Density Functional Theory, Spectroscopic and Receptor Binding Analysis of Pyriproxyfen – A Commercial Insect Growth Regulator

“…The experimental concentrations of DNA (100 μM) – PYR (0–6 μM) were prepared by further dilution and the spectra were recorded in 1.0 cm quartz cells. The experimental concentrations were selected on the basis of procedure described by Ponkarpagam et al [23] …”

“…Further, the peak position of CT‐DNA gets shifted towards shorter wavelengths with increase in PYR concentrations. From these observations, it can be concluded that PYR is responsible for the change in the helical structure of DNA and the mode of binding is suggested to be intercalation [23] . The binding constant (K b ) and free energy of binding ( ▵G b ) have been calculated using equations (6) and 7. $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr {{{A}_{0}}\over{A-{A}_{0}}}={{{{\rm \varepsilon{} }}_{G}}\over{{{\rm \varepsilon{} }}_{H-G}-{{\rm \varepsilon{} }}_{G}}}+{{{{\rm \varepsilon{} }}_{G}}\over{{{\rm \varepsilon{} }}_{H-G}-{{\rm \varepsilon{} }}_{G}}}{\rm \ }{{1}\over{{K}_{b}\left[PYR\right]}}\hfill\cr}}$$$ …”

“…From these observations, it can be concluded that PYR is responsible for the change in the helical structure of DNA and the mode of binding is suggested to be intercalation. [23] The binding constant (K b ) and free energy of binding ( ~Gb ) have been calculated using equations ( 6) and (7).…”