Fluoroquinolone
Saccharinates (FQ-SACs, P-060105581) are new salts of FQs regarded as
pharmaceutical alternatives. They have demonstrated an improvement in their organoleptic
properties when evaluated in animals and humans. The aim of this work was to
study aqueous solubility and pH compatibility of the saccharinate salts of the
FQs norfloxacin, ciprofloxacin and enrofloxacin in order to establish their
utility as pharmaceutical alternatives.
Solubility
studies were comparatively conducted at
FQ-SACs
are 5-20 times more soluble in water than their respective FQ precursor and
yield saturated solutions whose pH is higher than that of the respective
hydrochlorides (4.3-4.6). Solubility of FQ-SACs decrease with pH increase,
following the same pattern observed with the precursors. However, close to
neutrality, were minimum solubility is observed, norfloxacin and ciprofloxacin
salts are more soluble than expected. This behavior can be explained by ionic
pair formation and may occur at intestinal pHs in which the FQs are absorbed. The
increase observed in the solubility allows enlarging formulation possibilities and
might have an impact in the in vivo
amount of drug dissolved at intestinal level.