Hydroxypropyl β-cyclodextrin-crosslinked konjac glucomannan supramolecular hydrogel as dual-action drug carrier for a sustained release

A hydroxypropyl β-cyclodextrin (HPCD)/5-fluorouracil (5-FU) inclusion complex was loaded into konjac glucomannan hydrogel successfully by co-assembly. The influence of HPCD on the structure and properties of konjac glucomannan (KGM) hydrogel was investigated. The networks of KGM/HPCD hydrogel became flat and firm after HPCD intervened. The KGM/HPCD hydrogel had diversified microstructures including HPCD molecular cavities, porous lamellar structure in fibrous bands. The X-ray diffractometry (XRD) results reflected amorphous characters of the KGM/HPCD xerogel. The analytical data of Fourier transform infrared spectrometry (FT-IR) and differential scanning calorimetry (DSC) confirmed the supramolecular interactions between KGM and HPCD molecules in the gel network were mainly H-bonding interactions. HPCD improved KGM/HPCD hydrogel by crosslinking physically to construct a novel drug delivery system in the presence of sodium carbonate. The KGM/HPCD hydrogel achieved more effective and sustained drug release, in which HPCD cavities shared responsibility for the controlled release of chemotherapeutic 5-FU molecules. Rheological measurements also showed the presence of HPCD increased the elastic modulus (G') of the novel KGM/HPCD hydrogel.

Graphical abstract

Through co-assembly, a green drug delivery system was successfully constructed with hydroxypropyl β-cyclodextrin/5-fluorouracil inclusion complex loaded into konjac glucomannan hydrogel. By dialysis experiments, the drug 5-fluorouracil release rate from the inclusion complex loaded hydrogel was prolongated remarkably compared to that from single 5-fluorouracil loaded hydrogel. For the inclusion complex loaded hydrogel with different 5-fluorouracil concentrations, or under different physiological conditions, the drug cumulative release appeared also evident difference. This green drug delivery system has important potential application in medical engineering material.