Volumetric and viscometric properties of glycine and methionine (amino acids) in a 0.2 vol. % amikacin sulphate (antibiotic drug) aqueous solution with the molality range of 0.025 mol kg−1–0.25 mol kg−1 were measured over the temperature range of 20°C–40°C at the interval of 5°C. Different parameters like apparent molar volume (ϕ V), apparent molar adiabatic compression (ϕ κ), isentropic compression (κ S) along with other acoustical parameters were calculated. Parameters like viscous relaxation time (τ), free volume (V F), internal pressure (Π I), and molar cohesive energy (MCE) were calculated from dynamic viscosity measurements. The ϕ V values are positive in both cases, but with higher magnitude observed in methionine. These positive values of ϕ V are indicative of strong solute-solvent interactions at all temperatures. In case of methionine there is a sharp initial increase in the ϕ V values which become almost constant with further additions of the amino acid. Structural differences in the two amino acids studied are clearly reflected in the different nature of the plots of different parameters. In case of an amino acid-drug system, dynamic viscosity increase has been attributed to the increase in the hydrophilic-ionic and hydrophilic-hydrophilic interactions with the increase in the amino acid concentration which in turn may cause more frictional resistance to the flow of the solution. All other parameters are discussed in terms of solute-solvent and solvent-solvent interactions.

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Conductivity and spectroscopy techniques have been accomplished to comprehend the mechanism of supramolecular assembly of cetyltrimethylammonium bromide (CTAB) and dodecyltrimethylammonium bromide (DTAB) in aqueous solution of amikacin sulphate (0.001, 0.005, and 0.010 mol kg −1). For CTAB, the normal boost of the CMC value with rise in temperature manifests the significant role of aquaphilic dehydration. However, the aquaphobic dehydrations become prominent with temperature and depict typical U-shaped behavior of CMC for DTAB. The thermodynamic parameters of micellization have been derived from CMC values. The outcomes have been conferred in terms of solvation of hydrophobic part of surfactants by hydrophobic part of amikacin sulphate and micellization becomes more favorable for surfactant with more hydrophobic character in the presence of drug. The alteration in micro-environment of the ternary (drug/surfactant/water) system has been explained in terms of fluorescence emission intensity of surfactant solutions which has been found to decrease by the addition of drug. The obtained absorbance spectrum by varying concentrations of surfactant/drug affords noteworthy information regarding the diverse interactions in studied systems. Moreover, the exhaustive understanding of surfactant micellar behavior have been discussed in consideration of use of surfactants as drug delivery agents and hence to amplify drug bioavailability consequently remodeling its treatment efficacy.