Aggregation, interaction and thermodynamic characteristics of cationic surfactant + moxifloxacin hydrochloride mixture in aquatic solutions of mono-/di-hydroxy compounds

Abstract

Herein, the interaction of the fourth-generation fluoroquinolone antibiotic drug, moxifloxacin hydrochloride (MFH), which is extensively used for the treatment of wider ranges of bacterial infections, like pneumonia, endocarditis, tuberculosis, and other complicated dermal lesions, and cetyltrimethylammonium bromide (CTAB, a cationic surfactant) has been observed by conductivity method in aqueous, alcoholic (C₂H₅OH, C₃H₇OH-2), and diol (C₂H₄(OH)₂, C₃H₆(OH)₂) solutions. For all of the MFH + CTAB cases studied, the appearance of a critical micelle concentration (cmc) demonstrated that the micellar system is dependent on the variation of temperature and the concentration of different additives. A change in the value of cmc manifests the existence of strong interaction prevailing amongst MFH and CTAB molecules. In presence of alcohols/diols, the value of cmc for the MFH + CTAB system was found higher compared to those values obtained for the MFH + CTAB system carried out in H₂O, which indicates a favourable micellization process. The values of counter-ion dissociation were also found to be dependent on temperature. The $\mathrm{\Delta }{G}_m^o$ values were observed negative, which, again, manifests a spontaneous micellization process. The free energy of transfer ($\mathrm{\Delta }{G}_{m,tr}^o$) and the enthalpy–entropy compensation were also calculated and discussed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Moxifloxacin hydrochloride
• cetyltrimethylammonium bromide
• critical micelle concentration
• Gibbs free energy
• conductivity measurements

Acknowledgment

This work was funded by the Researchers Supporting Project Number (RSP-2020/138) King Saud University, Riyadh, Saudi Arabia.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

^a Declared by the supplier.

^a Relative standard uncertainties (u_r) limits are u_r(cmc) = ±3%, u_r(α) = ±4% and u_r(β) = ±4%.

^a Relative standard uncertainty (u_r) limit is u_r($\mathrm{\Delta }{G}_m^o$) = ±3%

^a Relative standard uncertainties (u_r) limits are u_r($\mathrm{\Delta }{G}_m^o$) = ±3% and u_r($\mathrm{\Delta }{G}_{m,tr}^o$) = ±4%

^a Relative standard uncertainty (u_r) limit is u_r($\mathrm{\Delta }{H}_m^{o,\ast }$) = ±4%.

Additional information

Funding

This work was supported by King Saud University: [Grant Number RSP-2020/138].