Meloxicam-LDH Hybrid Compound: A Successful Strategy to Improve Solubility

Abstract

The use of nanohybrids containing cationic or anionic inorganic compounds, seems particularly promising as efficient strategy for drug delivery. In fact, the inorganic counterions usually present in the host can be easily exchanged with drug molecules, from antitumor to anti-inflammatory, antibiotics and vitamins, giving rise to composites with improved solubility. An interesting inorganic host emerging for different applications, from catalysis to water purification up to pharmaceutics, is the layered double hydroxide (LDH) possessing a sheets structure and formula [$${\text{M}}_{{1 - {\text{x}}}}^{2 + }$$$${\text{M}}_{\text{x}}^{3 + }$$ (OH)2](An−)x/n yH2O (M2+ = Zn, Mg; M3+ = Al; An− = nitrates, carbonates, chlorides). In this paper, we synthesize by co-precipitation and reconstruction methods the hybrid compound Meloxicam-Zn3Al-LDH, particularly useful for a poorly soluble anti-inflammatory drug. The effective drug intercalation into LDH was verified through X-ray powder diffraction, thermal measurement and infrared spectroscopy. In addition, microscopy/microanalysis supported the formation of new entities. The dissolution tests clearly demonstrate an amazing improvement of the drug release rate with respect to marketed compounds when meloxicam is in the form of hybrid compound.