Cisplatin release from inclusion complex formed by oxidized carbon nanotube: A DFT study

Unveiling the Releasing Processes of Pt(II)-Based Anticancer Drugs from Oxidized Carbon Nanohorn: An In Silico Study

“…By decomposing the ΔΔ G ≠ into the enthalpic (ΔΔ H ≠ ) and entropic ( T ΔΔ S ≠ ) barriers, the data in Table reveal that the energetic barriers to the Pt­(II) drugs release from the CNHox are mostly enthalpic with an average entropic contribution of 34% considering all complexes. Using quantum calculations based on semirigid scan, in addition to showing a slight contribution of the entropy (∼0.1 kcal mol –1 ), De Souza et al showed that ∼95% of the free energy barrier referring to the cddp release from a CNTox prototype was composed of enthalpic contribution (ΔΔ H ≠ = 55.5 kcal mol –1 ). To determine the energetic components that govern the ΔΔ H ≠ , Figure S18 presents the profiles of the vdw and elec contributions of Δ b G for all processes.…”

“…As no theoretical data refer to the release process of both cpx and oxa from the CNH, we conducted some comparisons with the literature by taking into account the cddp1@CNHox and cddp2@CNHox complexes. In this context, De Souza et al 49 obtained a value of 58.4 kcal mol −1 for the energy barrier, referring to the release event of cddp from the cavity of a CNTox model. The notable difference of 40.19 kcal mol −1 in relation to the two complexes involving cddp presented herein (see Table 5) is probably an effect of the high steric hindrance of the nanowindow (diameter of ∼4.13Å) in the CNTox prototype, which made it difficult the diffusion of this Pt(II) drug (diameter of ∼7.75 Å) through this release pathway.…”

“…From semirigid scan calculations of the potential energy surface at the B3LYP/LANL2DZ/6-31G (gas phase) level, our group also demonstrated that the cddp release from a nanowindow of a CNTox model was thermodynamically favorable (ca. −25 kcal mol –1 ) and kinetically unfavorable with a free energy barrier of 58.4 kcal mol –1 …”

“…−25 kcal mol −1 ) and kinetically unfavorable with a free energy barrier of 58.4 kcal mol −1 . 49 To the best of our knowledge, previous studies have not provided a detailed molecular description of the releasing process of Pt(II)-based drugs approved worldwide from the nanowindows of CNH. Therefore, the present study intends to fill this gap by presenting an analysis focused on the energy profiles of the inclusion and adsorption processes involving Pt(II) anticancer drugs (cddp, cpx, and oxa) and a CNHox model.…”

Chemical Absorption of CO2 Enhanced by Solutions of Alkali Hydroxides and Alkoxides at Room Temperature

“…The theoretical calculation of thermodynamic parameters in the solution can help experimentalists in the discussion of the spontaneity of chemical reactions and physicochemical processes as elsewhere has been reported [48,49] . To assess the thermodynamic spontaneity of the organic carbonate formation reactions, the energy parameters were calculated according to equations (8)–10: $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr \Delta {\rm E}{_{{\rm F}}}={\rm E}{_{{\rm Carbonate}}}\hbox{-}({\rm E}{_{{\rm Alkoxide}}}+{\rm E}{_{{\rm CO2}}})\hfill\cr}}$$$ $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr \Delta {\rm H}{_{{\rm F}}}=\Delta {\rm E}{_{{\rm F}}}+\Delta {\rm H}{_{{\rm Thermal}}}\hfill\cr}}$$$ $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr \Delta {\rm G}{_{{\rm F}}}=\Delta {\rm H}{_{{\rm F}}}\hbox{-}{\rm T}\Delta {\rm S}\hfill\cr}}$$$ …”