Synthesis, optimization, and characterization of β-cyclodextrin-based biological metal-organic frameworks as drug carriers

In this study, beta-cyclodextrin (beta-CD)-based metal-organic frameworks (MOFs) were synthesized using the vapor diffusion method, a cost-effective and straightforward approach, to evaluate their potential as drug delivery systems. Ketoprofen (KP), a poorly water-soluble nonsteroidal anti-inflammatory drug (NSAID), was used as a model drug. The effects of reaction time, temperature, ligand-to-metal salt molar ratio and cetrimonium bromide (CTAB) surfactant addition on the properties of beta-CD-Bio-MOFs were systematically investigated. Optimal synthesis conditions-1 day, 30 degrees C, and a 1:4 beta-CD:KOH molar ratio-produced quadrilateral crystals averaging 10-20 mu m in size. Using KCl as the metal source yielded uniform crystals (10-40 mu m), whereas NaOH and FeCl3 did not result in consistent structures. Adding CTAB as a surfactant further reduced crystal sizes to 5-20 mu m. Also, KP loading experiments were conducted to optimize parameters such as temperature, agitation speed, loading time, solvent medium, and mass ratio for achieving maximum loading efficiency. The optimal conditions were determined to be 25 degrees C, 200 rpm, and 3 h in ethanol. Under these conditions, loading efficiencies of 13.4%, 9.6%, and 15.8% were achieved for beta-CD-Bio-MOF, KCl-beta-CD-Bio-MOF, and CTAB-beta-CD-Bio-MOF samples, respectively, with corresponding surface areas of 11.8, 9.7, and 18.4 m2 g-1. In comparison, pure beta-CD, with a specific surface area below 5 m2 g(-)1, exhibited a lower loading efficiency of 4.1%.