Molecular Dynamics Simulations of Interactions between Polyanilines in Their Inclusion Complexes with β-Cyclodextrins

Abstract

Conductive polymers have several applications such as in flexible displays, solar cells, and biomedical sensors. An inclusion complex of a conductive polymer and cyclodextrin is desired for some applications such as for molecular wires. In this study, different orientations of β-cyclodextrin rings on a single polyaniline (PANI) chain in an alternating emeraldine form were simulated using molecular dynamics. The simulations were performed in an implicit solvent environment that corresponds to experimental conditions. When the larger opening of the β-cyclodextrin toroids face the same direction, the cyclodextrins tend to repel each other. Alternating the orientation of the β-cyclodextrins on the chain causes the β-cyclodextrin rings to be more attractive to one another and form pairs or stacks of rings. These simulations explain how the β-cyclodextrins can be used to shield the polyaniline from outside chemical action by analyzing the PANI/cyclodextrin interactions from a molecular perspective.

Conductive Polymers: Opportunities and Challenges in Biomedical Applications

“…It is polymerized on the basis of the aniline monomer, and can be found in one of three idealized oxidation states, which affect its conductivity. The partially oxidized structure called emeraldine is also of interest and is shown in Figure , where m and n in the figure are in a 1:1 ratio . After being doped with acid, it becomes a CP which is very stable at room temperature.…”

“…This section explains the use of different materials for hybridization with polyaniline to improve the conductivity, such as cyclodextrin, β-cyclodextrin ring, lyotropic liquid crystalline (LLC) materials, platinum, oxidant ammonium peroxydisulfate, ATQD, and methyl orange (MO) …”

Cooperative Binding of Cyclodextrin Dimers to Isoflavone Analogues Elucidated by Free Energy Calculations

“…Many theoretical reports focused on the relative stability of noncovalent CD dimers in HH, HT, and TT fashions (Figure 1a) and revealed that hydrogen-bonding (HB) interactions between hydroxyl groups of adjacent CD monomers are a key factor determining the dimer stability. 31−36 Cai and co-workers recently examined dimerization of α-CDs onto a PEG chain using free energy calculations and Monte Carlo simulations. 37 They indicated that the dimerization is driven primarily by HB interactions between two α-CDs and that HH is preferred over HT and TT.…”

Heat‐Induced Supramolecular Organogels Composed of α‐Cyclodextrin and “Jellyfish‐Like” β‐Cyclodextrin–Poly(ε‐caprolactone)

“…Cyclodextrins (CDs) are a series of cyclic oligosaccharides composed of 6, 7, and 8 glucose units linked by α‐1,4‐linkages and named α‐CD, β‐CD, and γ‐CD, respectively. Since Harada and Kamachi first reported ICs resulting from poly(ethylene glycol) (PEG) and α‐CD in the 1990s, an enormous variety of ICs based on CDs and different polymers such as linear and branched polymers have been prepared and extensively investigated . Although CDs have been the most widely used and studied macrocyclic host molecules, most reports on ICs formed by CDs and guest molecules are about hydrogels while organogels are rarely reported …”

“…Since Harada and Kamachi 6 first reported ICs resulting from poly(ethylene glycol) (PEG) and a-CD in the 1990s, an enormous variety of ICs based on CDs and different polymers such as linear and branched polymers have been prepared and extensively investigated. 7,8 Although CDs have been the most widely used and studied macrocyclic host molecules, 9 most reports on ICs formed by CDs and guest molecules are about hydrogels [10][11][12] while organogels are rarely reported. 13 The supramolecular organogel is an important branch of material science.…”