Present studies focused on the in vitro testing, the solubility enhancement and the in vivo testing of methyl propyl trisulfide (MPTS), a newly identified sulfur donor to treat cyanide (CN) intoxication. To enhance the solubility of the lipophilic MPTS, various FDA approved co-solvents, surfactants and their combinations were applied. The order of MPTS solubility in the given co-solvents was found to be the following: ethanol >> PEG 200 ≈ PEG400 ≈ PEG300 > PG. The maximum solubility of MPTS was found at 90% ethanol of 177.11 ± 12.17 mg/ml. The order of MPTS solubility in different surfactants is Cremophor EL > Cremophor RH40 > polysorbate 80 > sodium deoxycholate > sodium cholate. The maximum solubility of 40.99 mg/ml was achieved with 20% Cremophor EL. A synergistic solubilizing effect encountered with the combination of 20% Cremophor EL + 75% ethanol lead to a 2900-fold increase (compared to water solubility) in solubility. The in vivo efficacy using intramuscular administration was determined on a therapeutic mice model and expressed as a ratio of CN LD50 with and without the test antidote(s) (APR). Intramuscular administration was shown to be effective and the therapeutic antidotal protection by MPTS alone and MPTS + thiosulfate (TS) was significantly higher than the present therapy of TS. © 2013 Elsevier B.V. All rights reserved.
Kovacs, K., Ancha, M., Jane, M., Lee, S., Angalakurthi, S., Negrito, M., … Petrikovics, I. (2013). Identification, solubility enhancement and in vivo testing of a cyanide antidote candidate. European Journal of Pharmaceutical Sciences, 49(3), 352–358. https://doi.org/10.1016/j.ejps.2013.04.007