Water-soluble galactosamine derivative of β-cyclodextrin as protective ligand and targeted carrier for delivery of toxic anthracycline drug

Bovine Serum Albumin - Hydroxyapatite Nanoflowers as Potential Local Drug Delivery System of Ciprofloxacin

Introduction

Hybrid nanoflowers are structures consisting of organic (enzymes, proteins, nucleic acids) and inorganic components (mostly metal phosphates) with a flower-like hierarchical structure. Novel hybrid nanoflowers based on bovine serum albumin (BSA) and hydroxyapatite (HA) were obtained and characterized. Study on BSA-HA nanoflowers as potential drug delivery system is reported for the first time.

Methods

Embedding ciprofloxacin in the structure of hybrid nanoflowers was confirmed by ATR-FTIR and thermogravimetric analysis. The inorganic phase of the nanoflowers was determined by X-ray diffraction. UV‒Vis spectroscopy was used to evaluate the release profiles of ciprofloxacin from nanoflowers in buffer solutions at pH 7.4 and 5. The agar disk diffusion method was used to study the antibacterial activity of the synthesized nanoflowers against Staphylococcus aureus and Pseudomonas aeruginosa.

Results

Bovine serum albumin - hydroxyapatite nanoflowers were obtained with diameters of ca. 1-2 µm. The kinetics of ciprofloxacin release from nanoflowers were described by the Korsmeyer-Peppas model. The antibacterial activity of the synthesized nanoflowers was demonstrated against S. aureus and P. aeruginosa, two main pathogens found in osteomyelitis.

Conclusion

The formulated nanoflowers may act as an efficient local antibiotic delivery system. Due to the use of nonhazardous, biodegradable components and benign synthesis, hybrid nanoflowers are very promising drug delivery systems that could be applied in the treatment of skeletal system infections.

Adjusting the Structure of β-Cyclodextrin to Improve Complexation of Anthraquinone-Derived Drugs

β-Cyclodextrin (CD) derivatives containing an aromatic triazole ring were studied as potential carriers of the following drugs containing an anthraquinone moiety: anthraquinone-2-sulfonic acid (AQ2S); anthraquinone-2-carboxylic acid (AQ2CA); and a common anthracycline, daunorubicin (DNR). UV-Vis and voltammetry measurements were carried out to determine the solubilities and association constants of the complexes formed, and the results revealed the unique properties of the chosen CDs as effective pH-dependent drug complexing agents. The association constants of the drug complexes with the CDs containing a triazole and lipoic acid (βCDLip) or galactosamine (βCDGAL), were significantly larger than that of the native βCD. The AQ2CA and AQ2S drugs were poorly soluble, and their solubilities increased as a result of complex formation with βCDLip and βCDGAL ligands. AQ2CA and AQ2S are negatively charged at pH 7.4. Therefore, they were less prone to form an inclusion complex with the hydrophobic CD cavity than at pH 3 (characteristic of gastric juices) when protonated. The βCDTriazole and βCDGAL ligands were found to form weaker inclusion complexes with the positively charged drug DNR at an acidic pH (pH 5.5) than in a neutral medium (pH 7.4) in which the drug dissociates to its neutral, uncharged form. This pH dependence is favorable for antitumor applications.