Dopamine delivery systems based on C60 and C24 with B and N as substituents

Two different options as potential dopamine delivery systems were investigated in this study: fullerene C60- and C24-like structures. The systems being investigated include C60, C59X, C58X2, C24, C23X, and C22X2 (X represents B or N). Electron donor acceptor capacity and interaction energies were reported. Systems with one B are better electron acceptors than those with one N. The interaction of compounds containing B with dopamine is more favorable than the interaction of systems containing N. For a dopamine delivery system, at least two conditions are necessary. The first is the stability of the carrier-dopamine compound. This condition is fulfilled because C60-based heterofullerenes with B and dopamine form stable structures. Also, dopamine with C24-based structures containing B or N form stable structures. The second is that the interaction energy should be lower than the energy that binds dopamine to the receptor. Systems that fulfill the second condition include C60 and C58B2. The other systems present interaction energies that exceed 40 kcal/mol. Dopamine will bond to these systems and will most probably not be delivered at the receptor site, but these systems that interact strongly with dopamine may serve as agonists because they are good electron donors like dopamine. Systems with B could be antagonists of dopamine since they are good electron acceptors. This idea might be interesting to explore through experiments because heterofullerenes with B and dopamine might serve as antipsychotics rather than dopamine delivery systems.