Characterization of folic acid/native cyclodextrins host–guest complexes in solution

Structural diversity in the host–guest complexes of the antifolate pemetrexed with native cyclodextrins: gas phase, solution and solid state studies

“…From the previous studies it is known that collision-induced dissociation (CID) experiments may be helpful in distinguishing between exclusion and inclusion complexes via comparison of the relative complex stabilities. For example, inclusion complexes of folic acid (FA) with β-CD and γ-CD are far more stable than exclusion associate of FA and α-CD [ 16 ]. From collisional experiments we have also learnt that augmented stability of both inclusion complexes is mainly due to the increase of electrostatic forces and hydrogen bonds between FA and β- or γ-CD in the gas phase.…”

“…The increased influence of hydrophobic effects on the overall stabilities of CDs/FA complexes was observed in experiments in which a mass spectrometer was treated as a detector for quantitative analysis of CDs/FA complexes. Only these experiments enabled the solution-like order of stability to be obtained [ 16 ]. Similarly to the CDs/FA complexes, PTX with α-CD, β-CD, and γ-CD forms stable noncovalent associates (1:1 host–guest) in the gas phase, which are detected as doubly negatively charged ions ([CD + PTX − 2H] 2− ) in the negative-ESI mass spectra (see Supporting Information File 1 : Figure S1a–c).…”

“…The gas-phase stability of such a complex, depending on the nature of interactions occurring between molecules within a complex, may reflect the solution binding behavior, in particular when polar interactions greatly contribute to the overall binding energy. Recent results concerning the studies of association modes between FA and CDs clearly showed that, although the overall gas-phase stabilities do not reflect the solution phase association constants, they are helpful in structural differentiation between inclusion and exclusion complexes [ 16 ]. The complexes in which a FA guest is trapped in the central cavity of CD in a form of pseudorotaxane structure are supposed to be substantially more stable than complexes with a ligand being associated with the CD’s surface or partially allied with CD’s internal space.…”

Cage to cage study of ionic liquid and cyclic oligosaccharides to form inclusion complexes

“…This study conrms the formation of two inclusion complexes with 1 : 1 stoichiometry. 34,35 2.9. Binding constants: non linear isotherms Association constants (K b ) of the two inclusion complexes have been determined from conductivity study.…”

New Insight into the Synthesis and Biological Activity of the Polymeric Materials Consisting of Folic Acid and β‐Cyclodextrin

“…The key points for the possible application of the FA‐targeted materials are (i) the level of the cellular uptake of FA and (ii) their cytotoxicity toward cancer cells. What is more important, there are articles reporting the inclusion of FA via the aromatic part of its structure into the interior of βCD . However, the possible limiting of the biological activity of FA in the covalent nanotherapeutic systems consisting of βCD has not been discussed in the literature up to date.…”