Binding of Sulfamethazine to β-cyclodextrin and Methyl-β-cyclodextrin

Abstract

β-cyclodextrin (βCD) and methyl-β-cyclodextrin (MβCD) complexes with sulfamethazine (SMT) were prepared and characterized by different experimental techniques, and the effects of βCD and MβCD on drug solubility were assessed via phase-solubility analysis. The phase-solubility diagram for the drug showed an increase in water solubility, with the following affinity constants calculated: 40.4±0.4 (pH 2.0) and 29.4±0.4 (pH 8.0) M(-1) with βCD and 56±1 (water), 39±3 (pH 2.0) and 39±5 (pH 8.0) M(-1) with MβCD. According to (1)H NMR and 2D NMR spectroscopy, the complexation mode involved the aromatic ring of SMT included in the MβCD cavity. The complexes obtained in solid state by freeze drying were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and thermal analysis. The amorphous complexes obtained in this study may be useful in the preparation of pharmaceutical dosage forms of SMT.

Increasing Doxycycline Hyclate Photostability by Complexation with β-Cyclodextrin

“…1b) constitutes the most widely used macromolecule due to its low industrial cost. Complexation of drugs with CD has been used to increase their solubilities and stabilities, as well as to modulate the organoleptic properties of pharmaceutical formulations (8)(9)(10). The effect of IC formation on the photostability of different drugs has also been previously studied, with reports showing that complexation with CD can significantly affect the light absorption properties of the included compound (11).…”

Effect of Methyl-Β-Cyclodextrin Complexation on the Hypoglycemic and Hypolipidemic Effects of Khellin: Experimental Study

“…Among the prepared complexes, FD showed the highest dissolution profile with an accumulative dissolution more that 85% and 90 % after 30 and 60 min. The observed increase of KH dissolution profile obtained in case of FD complex was probably due to amorphization of the drug by applying the freeze-drying method resulting in better wettability and consequently increases the drug solubility which likely contributed to the enhanced dissolution of the complex [50,51]. Also, the increase in dissolution efficiency can be attributed to the reduction of crystalline nature of KH [52] A comparison between the complexes prepared by various methods was made by determination of the dissolution efficiency (D. E.) [53].…”

Thermodynamic Characterization of the Interaction between the Antimicrobial Drug Sulfamethazine and Two Selected Cyclodextrins

“…Furthermore, sulfonamides can appear as contaminants in various foods, which may cause adverse health effects [15][16][17]. The host-guest type complex formation of these antibiotics with CDs is an extensively studied field [18][19][20][21][22][23][24]. Zoppi et al focus on the increased water solubility of sulfonamide drugs in the presence of native and methylated β-CD [23,24].…”

“…The host-guest type complex formation of these antibiotics with CDs is an extensively studied field [18][19][20][21][22][23][24]. Zoppi et al focus on the increased water solubility of sulfonamide drugs in the presence of native and methylated β-CD [23,24]. In the case of sulfamethazine (SMT), their nuclear magnetic resonance (NMR) and molecular modeling results demonstrate that SMT included the substituted pyrimidine ring into the β-CD cavity.…”

“…The pH-responsive host-guest encapsulation is also a highly studied field in material sciences [27] and in pharmacology [28,29]. Therefore, besides the complex stability and stoichiometry of SMT -β-CD complex and along the contradictory description of the related structures [18,23,24], the investigation of the pH dependence interaction of SMT with CDs is also reasonable.In our recent study [30], we demonstrated the importance of pH-dependent dipole moment of SMT molecule, which phenomenon can affect the complex geometry formed with β-CD (BCD) and randomly methylated β-CD (RAMEB) (Figure 1). Now we focus on the thermodynamic properties of the formation of inclusion complexes at different pH values.…”