Study on the inclusion complexes of bromazepam with β- and β-hydroxypropyl-cyclodextrins

Archontaki, Helen; Vertzoni, Maria; Athanassiou-Malaki, M.H.

doi:10.1016/s0731-7085(01)00679-3

Cited by 67 publications

(31 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This structure possesses a hydrophobic inner cavity and hydrophilic outer surface which allows the formation of inclusion complexes in which lipophilic compounds are noncovalently bound within the cavity. Cyclodextrins are popular for their ability to form inclusion complex and has been extensively used to enhance the aqueous solubility, stability, and dissolution rate of poorly water-soluble drugs [7][8][9]. Beta cyclodextrins (β-CDs) are most commonly used because of lower toxicities than other CDs, and their cavity size is suitable for a wide range of guest molecules.…”

Section: Introductionmentioning

confidence: 99%

Effects of the Preparation Method on the Formation of True Nimodipine SBE-β-CD/HP-β-CD Inclusion Complexes and Their Dissolution Rates Enhancement

et al. 2014

View full text Add to dashboard Cite

Abstract. The aims of this study were to enhance the solubility and dissolution rate of nimodipine (ND) by preparing the inclusion complexes of ND with sulfobutylether-b-cyclodextrin (SBE-β-CD) and 2-hydroxypropyl-b-cyclodextrin (HP-β-CD) and to study the effect of the preparation method on the in vitro dissolution profile in different media (0.1 N HCl pH 1.2, phosphate buffer pH 7.4, and distilled water). Thus, the inclusion complexes were prepared by kneading, coprecipitation, and freeze-drying methods. Phase solubility studies were conducted to characterize the complexes in the liquid state. The inclusion complexes in the solid state were investigated with differential scanning calorimetry (DSC), Xray diffractometry (X-RD), and Fourier transform infrared spectroscopy (FT-IR). Stable complexes of ND/SBE-β-CD and ND/HP-β-CD were formed in distilled water in a 1:1 stoichiometric inclusion complex as indicated by an A L -type diagram. The apparent stability constants (Ks) were 1334.4 and 464.1 M −1 for ND/SBE-β-CD and ND/HP-β-CD, respectively. The water-solubility of ND was significantly increased in an average of 22-and 8-fold for SBE-β-CD and HP-β-CD, respectively. DSC results showed the formation of true inclusion complexes between the drug and both SBE-β-CD and HP-β-CD prepared by the kneading method. In contrast, crystalline drug was detectable in all other products. The dissolution studies showed that all the products exhibited higher dissolution rate than those of the physical mixtures and ND alone, in all mediums. However, the kneading complexes displayed the maximum dissolution rate in comparison with drug and other complexes, confirming the influence of the preparation method on the physicochemical properties of the products.

show abstract

Section: Introductionmentioning

confidence: 99%

Effects of the Preparation Method on the Formation of True Nimodipine SBE-β-CD/HP-β-CD Inclusion Complexes and Their Dissolution Rates Enhancement

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Complexation with cyclodextrins (CDs) has been widely used to enhance the solubility and dissolution rate of poorly soluble drugs [8][9][10]. The most important structural feature of CDs is the hydrophobic central cavity capable of forming stable complexes with properly sized drug molecules [11,12].…”

Section: Introductionmentioning

confidence: 99%

Complexation of capsaicin with β-cyclodextrins to improve pesticide formulations: effect on aqueous solubility, dissolution rate, stability and soil adsorption

Shen

Yang

Zhou

et al. 2011

J Incl Phenom Macrocycl Chem

View full text Add to dashboard Cite

The binary systems of capsaicin (CP) and b-cyclodextrin (bCD) or hydroxypropyl-b-cyclodextrin (HPbCD) were investigated in an attempt to improve formulations of this pesticide. UV spectral shift methods indicated guest-host complex formation between CP and the two cyclodextrins (CDs). Phase solubility analysis showed B s type diagrams with bCD, A L type with HPbCD indicating the formation of an inclusion complex at 1:1 stoichiometric ratio in solution state. Solubility profiles indicated a 50-fold enhancement of CP solubility could be achieved in the presence of 60 mM HPbCD with respect to CP alone. Solid co-evaporated systems (CES) with 1:0.5-1:5 molar ratios of CP/CDs were physicochemically characterized, revealing that the true inclusion complexes could be formed in the solid CP/bCD systems with 1:5 molar ratio and in the solid CP/HPbCD systems with the molar ratios more than 1:3, respectively. In contrast, crystalline drug was detectable in all other systems. Compared with corresponding physical mixtures (PMs), the CES exhibited significant enhancement with regard to CP dissolution and the protection from CP degradation under the accelerated conditions. It was also revealed that complexation of CP with HPbCD had a pronounced improved effect on the pesticide formulations and greatly reduced the amount of CP adsorbed in the soil. These results demonstrate that HPbCD may be a preferred excipient, enabling more efficient and intelligent use of CP/ CDs inclusion complexes in the development of pesticide formulations.

show abstract

“…At pH higher than 7, the solubility is drastically reduced and this is a relevant issue, because the intestinal pH of some fish can reach values of 7 -9 8 . Actually, the salmon industry is concerned about the need for optimize the therapeutic regimes, and one way to achieve predictable drug concentrations in plasma and tissues (taking into account the low and pH dependent solubility of EB) after an oral dose of a drug is improving its aqueous solubility with the use of cyclodextrins [9][10][11][12] . Of all the cyclodextrins used, hydroxypropyl-β-cyclodextrin (HP-β-CD) has been the most studied, because of its toxicological profile and better aqueous solubility [13][14][15] .…”

Section: -Introduction Emamectin Benzoate (4′'r)-4″-deoxy-4″-(methmentioning

confidence: 99%

Preparation and Characterization of the Emamectin Benzoate/Hydroxypropyl-B-Cyclodextrin Inclusion Complex

Torres¹,

Villa²,

González³

et al. 2011

J. Chil. Chem. Soc.

View full text Add to dashboard Cite

The objective of this study was to prepare an inclusion complex of the insecticide emamectin benzoate (EB) with hydroxypropyl-β-cyclodextrin (HP-β-CD) by co-evaporation and spray drying methods. The complexation of both compounds was evaluated on the aqueous and solid state using phase solubility diagrams, differential scanning calorimetry (DSC), X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The aqueous solubility of the inclusion complexes at pH 8 had a 2-fold increase respect to the drug alone and dissolution profiles showed a rise in the dissolution rate. These results suggest that the use of HP-β-CD could be an interesting alternative to enhance the bioavailability of EB in salmons.Key Words: Emamectin benzoate, cyclodextrin, inclusion complex, salmon.e-mail: cvonples@udec.cl 1.-INTRODUCTIONEmamectin benzoate, (4′'R)-4″-deoxy-4″-(methylamino)avermectin b1 benzoate, is one of the most widely used compounds in the salmon industry. Chemically, is a semisynthetic derivative of avermectins (Figure 1), which shows insecticide properties against the sea lice (Lepeophteirus salmonis), an ectoparasite that infests farmed salmons [1][2][3] . Unfortunately, it has been demonstrated that the efficacy of anti-infective treatments in salmons and trouts is low because is very difficult to control the dosage in medicated foods, which results in high intra-inter variability in plasma concentrations of the agents used [4][5][6] Of the approaches considered for improvement of the accuracy in the administration of EB, Glover et al. demonstrated that the intraperitoneal injection of the drug in farmed salmons resulted in higher and more predictable concentrations, but there are constraints that have relation with the manipulation of individual specimens 7 . From a point of view of the drug, one of the factors that influence the bioavailability of active compounds in living systems are their physicochemical properties like the solubility, which is often the limiting step in the absorption process. EB is a compound that has an erratic bioavailability and poor water solubility, which depends on the pH of the aqueous medium. At pH higher than 7, the solubility is drastically reduced and this is a relevant issue, because the intestinal pH of some fish can reach values of 7 -9 8 . Actually, the salmon industry is concerned about the need for optimize the therapeutic regimes, and one way to achieve predictable drug concentrations in plasma and tissues (taking into account the low and pH dependent solubility of EB) after an oral dose of a drug is improving its aqueous solubility with the use of cyclodextrins [9][10][11][12] . Of all the cyclodextrins used, hydroxypropyl-β-cyclodextrin (HP-β-CD) has been the most studied, because of its toxicological profile and better aqueous solubility [13][14][15] . Since there is no evidence of previous research, the aim of this work is to study the possibility of form an inclusion complex of EB and HP-β-CD, characterizing the...

show abstract

Study on the inclusion complexes of bromazepam with β- and β-hydroxypropyl-cyclodextrins

Cited by 67 publications

References 17 publications

Effects of the Preparation Method on the Formation of True Nimodipine SBE-β-CD/HP-β-CD Inclusion Complexes and Their Dissolution Rates Enhancement

Effects of the Preparation Method on the Formation of True Nimodipine SBE-β-CD/HP-β-CD Inclusion Complexes and Their Dissolution Rates Enhancement

Complexation of capsaicin with β-cyclodextrins to improve pesticide formulations: effect on aqueous solubility, dissolution rate, stability and soil adsorption

Preparation and Characterization of the Emamectin Benzoate/Hydroxypropyl-B-Cyclodextrin Inclusion Complex

Contact Info

Product

Resources

About