Improving the Carprofen Solubility: Synthesis of the Zn2Al-LDH Hybrid Compound

The development of efficient strategies for drug delivery is considerably desired. Indeed, often several
issues such as the drug solubility, the control of the drug release rate, the targeted delivery of drugs, the
drug bioavailability, and the minimization of secondary effects still present great obstacles. Different
methodologies have been proposed, but the use of nano-hybrids compounds that combine organic and
inorganic substances seems particularly promising. An interesting inorganic host is the layered double
hydroxide (LDH) with a sheets structure and formula [M2þ
1x M3þ
x (OH)2](An)x/n yH2O (M2þ ¼ Zn, Mg;
M3þ ¼ Al; An ¼ nitrates, carbonates, chlorides). The possibility to exchange these counterions with drug
molecules makes these systems ideal candidates for the drug delivery. In this article, we synthesize by
co-precipitation method the hybrid compound Carprofen-Zn2Al-LDH. Carprofen, a poorly soluble antiinflammatory
drug, could also benefit of the association with a natural antacid such as LDH, to reduce
the gastric irritation after its administration. Through X-ray diffraction and Fourier-transformed infrared
spectroscopy (FT-IR), we could verify the effective drug intercalation into LDH. The dissolution tests
clearly demonstrate a significant improvement of the drug release rate when carprofen is in the form of
hybrid compound