Abbul Bashar Khan

Interaction of amphiphilic drugs with human and bovine serum albumins

To know the interaction of amphiphilic drugs nortriptyline hydrochloride (NOT) and promazine hydrochloride (PMZ) with serum albumins (i.e., human serum albumin (HSA) and bovine serum albumin (BSA)), techniques of UV-visible, fluorescence, and circular dichroism (CD) spectroscopies are used. The binding affinity is more in case of PMZ with both the serum albumins. The quenching rate constant (k(q)) values suggest a static quenching process for all the drug-serum albumin interactions. The UV-visible results show that the change in protein conformation of PMZ-serum albumin interactions are more prominent as compared to NOT-serum albumin interactions. The CD results also explain the conformational changes in the serum albumins on binding with the drugs. The increment in %α-helical structure is slightly more for drug-BSA complexes as compared to drug-HSA complexes.

Spectroscopic approach of the interaction study of amphiphilic drugs with the serum albumins.

The interaction of the amphiphilic drugs, i.e., amitriptyline hydrochloride (AMT) and promethazine hydrochloride (PMT), with serum albumins (i.e., human serum albumin (HSA) and bovine serum albumin (BSA)), has been examined by the various spectroscopic techniques, like fluorescence, UV-vis, and circular dichroism (CD). Fluorescence results indicate that in case of HSA-drug complexes the quenching of fluorescence intensity at 280 nm is less effective as compared to at 295 nm while in case of BSA-drug complexes both have almost same effect and for most of drug-serum albumin complexes there is only one independent class of binding. For all drug-serum albumin complexes the quenching rate constant (K(q)) values suggest the static quenching procedure. The UV-vis results show that the change in protein conformation of PMT-serum albumin complexes was more prominent as compared to AMT-serum albumin complexes. The CD results also explain the conformational changes in the serum albumins on binding with drugs. The increase in α-helical structure for AMT-serum albumin complexes is found to be more as compared to PMT-serum albumin complexes. Hence, the various spectroscopic techniques provide a quantitative understanding of the binding of amphiphilic drugs with serum albumins.

Mixed micellization of antidepressant drug amitriptyline hydrochloride with cationic surfactants

The surface tension measurements have been carried out on aqueous solutions of antidepressant drug amitriptyline hydrochloride with six cationic surfactants (decyl-, dodecyl-, tetradecyl-, cetyltrimethylammonium bromide, cetylpyridinium bromide and cetylpyridinium chloride) at different mole fractions to study the surface and micellar properties at the interface as well as in the micelles. The properties studied include critical micelle concentration (cmc), Gibbs surface excess (Gamma(max)), minimum head group area at the air/water interface (A(min)), free energy of micellization (DeltaG(m)( composite function)), and standard Gibbs energy of adsorption (DeltaG(ads)( composite function)), while synergistic behavior of drug-surfactant binary mixtures was analysed using Clints and Rubinghs models. Deviations of cmc from cmc(*) and X(1)(m) from X(1)(ideal) indicate the synergistic behavior (i.e., non-ideal behavior) for the drug-surfactant binary mixtures. The values of interaction parameters beta and activity coefficients f(1) and f(2) (for both, in mixed monolayer as well as in mixed micelles) also indicate the synergistic behavior. The excess free energy (DeltaG(ex)) for the drug-surfactant binary mixtures explains stability of mixed micelles in comparison to micelles of pure drug and variation with alkyl chain length of surfactants.

Mixed Micellization and Interfacial Properties of Nonionic Surfactants with the Phenothiazine Drug Promazine Hydrochloride at 30 °C

In the present work, the micellization and adsorption behaviors of mixed systems containing an amphiphilic phenothiazine drug, promazine hydrochloride (PMZ) and nonionic surfactants in aqueous media at different mole fractions of nonionic surfactants (α1) were investigated at 30 °C by surface tension measurements. The critical micelle concentrations of the mixtures fall between the values of the individual components, which indicates nonideal mixing. With Tritons the interactions are repulsive at low mole fractions. At high α1 the mixing becomes almost ideal. On the basis of regular solution theory, the micellar mole fractions of surfactants (

Hydrogen bonding-assisted interaction between amitriptyline hydrochloride and hemoglobin: spectroscopic and molecular dynamics studies

X_{1}^{m}

Solution and surface properties of amphiphilic drug – nonelectrolyte systems

) and interaction parameter (βm) were evaluated, while their interfacial mole fractions (

Solvatochromic Absorbance Probe Behavior within Mixtures of the Ionic Liquid 1-Butyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide + Molecular Organic Solvents

X_{1}^{\sigma}

Energetics of Drug-Additive Systems at the Cloud Point †

) and interaction parameters at the interface (βσ) were calculated using Rosen’s model. The results indicate that the surfactant’s contribution is greater than that of the drug both at the interface and in micelles. The short and rigid hydrophobic structure of the drug resists its participation in micelle formation more than in the monolayer, leading to

A study of the interaction between a phenothiazine drug promazine hydrochloride with cationic surfactants

X_{1}^{m}<X_{1}^{\sigma}

Effect of cationic gemini surfactant and its monomeric counterpart on the conformational stability and esterase activity of human serum albumin

. Values of the surface excess (Γmax) and minimum area per head group (Amin) indicate attractive interactions. Γmax increases and Amin decreases as the surfactant mole fraction increases.