Premium
Note of Caution for the Aqueous Behaviour of Metal‐Based Drug Candidates
Author(s) -
Notaro Anna,
Gasser Gilles,
Castonguay Annie
Publication year - 2020
Publication title -
chemmedchem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.817
H-Index - 100
eISSN - 1860-7187
pISSN - 1860-7179
DOI - 10.1002/cmdc.201900677
Subject(s) - solubility , aqueous solution , colloid , solvent , ruthenium , chemistry , drug , metal , nanotechnology , organic chemistry , materials science , catalysis , medicine , pharmacology
Poor aqueous solubility is one of the recurrent drawbacks of many compounds in medicinal chemistry. To overcome this limitation, the dilution of drug candidates from stock solutions of an organic solvent is common practice. However, the precise characterisation of these compounds in aqueous solutions is often neglected, leading to some uncertainties regarding the nature of the actual active species. In this communication, we demonstrate that two ruthenium complexes previously reported by our group for their chemotherapeutic potential against cancer, namely [Ru(DIP) 2 (sq)](PF 6 ) and [Ru(DIP) 2 (3‐methoxysq)](PF 6 ), where DIP is 4,7‐diphenyl‐1,10‐phenanthroline, sq=semiquinonate and 3‐methoxysq=3‐methoxysemiquinonate, form colloids in water‐DMSO (1 % v/v) mixtures that are invisible to the naked eyes. [Ru(DIP) 2 (3‐methoxysq)](PF 6 ) was found to form a highly stable and monodispersed colloid with nanoaggregates of ∼25 nm. In contrast, [Ru(DIP) 2 (sq)](PF 6 ) was found to form large reticulates of mostly spherical aggregates which size was found to increase over time. The difference in size and shape distribution of drug candidates is of tremendous significance as the study of their biological activity might be severely affected. Overall, we strongly believe that these observations should be taken into account by the scientific community working on the development of metal‐based drugs with poor water solubility.