A Molecular Dynamics Study of a Photodynamic Sensitizer for Cancer Cells: Inclusion Complexes of γ-Cyclodextrins with C70

Abstract

Photodynamic therapy is an emerging treatment of tumor diseases. The complexes with γ-cyclodextrins (γ-CD) and fullerenes or their derivatives can be used as photosensitizers by direct injection into cancer cells. Using molecular mechanics and molecular dynamics methods, the stability and the geometry of the 2:1 complexes [(γ-CD)2/C70] are investigated analyzing the differences with the analogous C60 complexes, studied in a previous theoretical work and experimentally found to be much less efficient in cancer therapy. The inclusion complex of γ-CD and C70 has a 2:1 stoichiometry, the same as C60, but is significantly less stable and displays an unlike arrangement. In vacuo, mimicking an apolar solvent, the complex is compact, whereas in water the two γ-CDs encapsulate C70 forming a relatively stable complex by interacting through their primary rims, however exposing part of C70 to the solvent. Other higher-energy complexes with the γ-CDs facing different rims can form in water, but in all cases part of the hydrophobic C70 surface remains exposed to water. The stability and arrangement of these peculiar amphiphilic inclusion complexes having non-covalent interactions in water can be an important key for cancer therapy to enhance both the solubilization and the fullerene insertion into liposomes or cell membranes.

Understanding Surface Interaction and Inclusion Complexes between Piroxicam and Native or Crosslinked β-Cyclodextrins: The Role of Drug Concentration

“…Over the past 20 years, molecular mechanics (MM) and molecular dynamics (MD) simulations have been demonstrated to be a useful tool in order to atomistically investigate and describe non-covalent interactions in different systems ranging from protein adsorption on surfaces of biomaterials to formation and self-aggregation of host–guest complexes, including their stoichiometry and self-aggregation in an nonpolar solvent or in water [ 20 , 21 , 22 , 23 , 24 , 25 , 26 ]. Molecular simulation studies offer great insights into these phenomena in very good agreement with experimental data [ 20 , 27 , 28 , 29 ].…”

Inclusion Complexes Between β‐cyclodextrin and the Anticancer Drug 5‐Fluorouracil for its Solubilization: a Molecular Dynamics Study at Different Stoichiometries

“…In a future work, the same theoretical study in explicit water will be presented in order to confirm these preliminary results. It will also be important to study stable complexes 𝛽-CD:5-FU in 2:1 stoichiometry, [21,22] thus reducing the amount of drug in the complexes, then its possible toxicity side effects. In general, the attention will focus on the interaction between 5-FU and 𝛽-CD at different concentrations with possible interaction also on the external surface of 𝛽-CD aggregates as found for piroxicam drug molecules interacting with of 𝛽-CD nanosponges.…”

The Physical Chemistry and Chemical Physics (PCCP) Section of the International Journal of Molecular Sciences in Its Publications: The First 300 Thematic Articles in the First 3 Years

“…In this Thematic Area, 56 articles have been published [ 48 , 64 , 104 , 108 , 110 , 124 , 195 , 252 , 253 , 254 , 255 , 256 , 257 , 258 , 259 , 260 , 261 , 262 , 263 , 264 , 265 , 266 , 267 , 268 , 269 , 270 , 271 , 272 , 273 , 274 , 275 , 276 , 277 , 278 , 279 , 280 , 281 , 282 , 283 , 284 , 285 , 286 , 287 , 288 , 289 , 290 , 291 , 292 , 293 , 294 , 295 , 296 , 297 , 298 , 299 , 300 ], an...…”

“…A more detailed examination shows that, in this direction, as well as in the previous ones, articles in which the objects of research are organic materials clearly prevail over articles in which the objects of research are inorganic materials (36 and 20, respectively). Wherein, the overwhelming majority of articles of the “organic” profile are, in one way or another, connected with the participation of the objects with a biological origin; these include [ 64 , 124 , 254 , 255 , 256 , 257 , 258 , 259 , 260 , 261 , 262 , 263 , 274 , 277 , 278 , 282 , 284 , 289 , 291 , 292 , 293 , 294 , 295 , 296 , 298 , 299 , 300 ] and the processes in abiogenic organic materials were considered only in [ 48 , 195 , 266 , 271 , 272 , 273 , 283 , 288 , 290 ]. The thematic focus of these works, as well as the chemical compounds studied in them, is also very diverse, and even a simple listing of them here is clearly beyond the scope of this article, too.…”