Intercalation compounds of hydrotalcite-like anionic clays with anti-inflammatory agents, II: Uptake of diclofenac for a controlled release formulation

Abstract

ABASTRACT The purpose of this study was to investigate whether hydrotalcite is able to intercalate diclofenac, a nonsteroidal anti-inflammatory drug, and release it in a controlled manner. Layered Mg-Al hydrotalcite in the chloride form was used as a host, and the intercalation compound was prepared by Cl -/diclofenac anionic exchange. Drug release from the intercalation compound was performed in vitro in simulated intestinal fluid at pH 7.5 according to USP 24 and in a pH 7.0 solution designed to mimic the ionic conditions of the small intestine. Results from the intercalation process show that hydrotalcite is able to intercalate diclofenac with a simple procedure and with a good drug loading (55% wt/wt). The in vitro drug release was remarkably lower than that from the corresponding physical mixture at both pH 7.5 and pH 7.0. In the latter case, the release was not complete at 24 hours. The kinetic analysis shows the importance of the diffusion through the particle in controlling the drug release rate. The obtained results show that hydrotalcite may be used to prepare modified release formulations.

Influence of Hydrothermal Treatment on Physicochemical Properties and Drug Release of Anti-Inflammatory Drugs of Intercalated Layered Double Hydroxide Nanoparticles

“…Calculated by averaging d 003 , 2 d 006 and 3 d 009 , the interlayer spacings of the LDH–NAP–HT/FP, LDH–DIC–HT/FP and LDH–IBU–HT/FP were 2.12, 2.19, 2.26, 2.25, 2.15 and 2.14 nm, respectively (Table 2), in correspondence with the interlayer spacing of LDH–NAP/DIC/IBU using various synthesis methods reported in the literature [14,25,26,27,28,29,30]. The same interlayer spacing of LDH–drug before and after hydrothermal treatment suggests that hydrothermal treatment did not affect the drug anion arrangement in the LDH interlayer.…”

“…As expected, the molar ratio of Mg to Al in all samples was around 2.0 and slightly decreased after hydrothermal treatment, probably due to the slightly higher solubility of Mg–hydroxide at the higher temperature. The drug loading capacity of LDH–NAP/DIC/IBU was 39.0%–47.4%, close to or lower than that reported in the literature [14,25,27,28,29,30]. For example, Costantino and coworkers reported that the drug loading capacity of DIC and IBU in LDH was 55% and 50%, respectively [29].…”

“…The spectra of LDH–drug samples showed the characteristic peaks of the LDH materials [9]: (1) the intense broad band around 3300–3500 cm −1 associated with the stretching vibration of O–H in the brucite-like layer and water molecules; (2) the band at 544 cm −1 attributed to the M–O and M–O–H stretching vibrations; and (3) the peak at 440 cm −1 , particularly characteristic of Mg 2 Al–LDH materials. Bands around 1570 and 1400 cm −1 in the LDH–drug spectra were attributed to the asymmetric and symmetric stretching vibrations of carboxylate, respectively [27,32]. The asymmetric carboxylate band moved to a lower frequency compared with the corresponding bands in drug-sodium salt, due to the strong electrostatic interactions between drug COO − groups and LDH layers.…”

Anticancer Activity of Ferulic Acid‐Inorganic Nanohybrids Synthesized via Two Different Hybridization Routes, Reconstruction and Exfoliation‐Reassembly

“…As the molecular dimension of FA was ~1.01 nm which was larger than CO 3 2− or NO 3 − , the interlayer distance of LDH significantly expanded upon the intercalation of FA. According to the previous reports on FL nanohybrids, the interlayer distance of 1.2~1.3 nm stood for the zig-zag orientation of FA molecules enhancing their interlayer stabilization via π - π interaction of aromatic groups [13, 25]. …”

Montmorillonite-alginate composites as a drug delivery system: Intercalation and In vitro release of diclofenac sodium

“…A particular attention has been paid to find a way to regulate the rate of drug release by a carrier where the drug is dispersed or incorporated in an inert matrix[12]. To develop such carriers much attention has been paid to study the interaction between the host and the guest (drugs) compounds.…”