Synthesis and Properties of New Multilayer Chitosan@layered Double Hydroxide/Drug Loaded Phospholipid Bilayer Nanocomposite Bio-Hybrids

Abstract

A novel bio-hybrid drug delivery system was obtained involving a Mg/Al-NO3 layered double hydroxide (LDH) intercalated either with ibuprofenate anions (IBU) or a phospholipid bilayer (BL) containing a neutral drug, i.e., 17β-estradiol, and then embedded in chitosan beads. The combination of these components in a hierarchical structure led to synergistic effects investigated through characterization of the intermediates and the final bio-composites by XRD, TG, SEM, and TEM. That allowed determining the presence and yield of IBU and of BL in the interlayer space of LDH, and of the encapsulated LDH in the beads, as well as the morphology of the latter. Peculiar attention has been paid to the intercalation process of the BL for which all available data substantiate the hypothesis of a first interaction at the defect of the LDH, as well as on the interaction mode of these components. 1H, 31P and 27Al MAS-NMR studies allowed establishing that the intercalated BL is not homogeneous and likely formed patches. Release kinetics were performed for sodium ibuprofenate as well as for the association of 17β-estradiol within the negatively charged BL, each encapsulated in the LDH/chitosan hybrid materials. Such new bio-hybrids offer an interesting outlook into the pharmaceutical domain with the ability to be used as sustained release systems for a wide variety of anionic and, importantly, neutral drugs.

Preparation and Characterization of Chitosan/LDH Composite Membranes for Drug Delivery Application

“…The first step, between 50 and 130 °C, was due to the evaporation of interlay water molecules, and the second step, between 160 and 400 °C, was attributed to the degradation of the amino/N-acetyl groups from the CS chain [ 65 , 66 , 67 , 68 ]. Moreover, in the case of CS-LDH-DCF composite membrane, a new small weight change, between 400 and 520 °C, could be observed and was due to the degradation of the interlayer anionic species and also to the dehydroxylation of the brucite-like structure of LDH [ 54 , 69 ]. Furthermore, an increase in the residual mass loss in the case of the CS-LDH-DFC composite membranes has also been recorded.…”

“…The drug release is facilitated by the protonation of the functional groups of chitosan and the interlayer anions in LDH, leading to a high swelling of the samples at lower pH values. Lerner et al [ 54 ] proposed chitosan/Mg/Al-NO3 layered double hydroxide (LDH) intercalated either with ibuprofenate anions (IBU) or a phospholipid bilayer (BL) containing a neutral drug. In this case, the release is triggered by the pH variation of the physiological environment, so that the release mechanism from the intercalated compounds occurs by the exchange between IBU and the buffer phosphate ions diffusing through the net of the polymer chains.…”

“…Diclofenac is loaded by the intercalation between the LDH layers and coated with chitosan to facilitate a gradual release, avoiding the rapid release of diclofenac in the first hours. The release mechanism occurs due to the ion exchange diffusing through the net of the polymer chains [ 54 ]. These composite membranes were evaluated from a morphological point of view through Scanning Electron Microscopy (SEM) and physico-chemical properties via Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS) and Thermogravimetric Analysis (TGA) in order to evaluate the possibility of use in biomedical applications such as controlled release systems.…”

Special Issue: Layered Double Hydroxides (LDH) and LDH-Based Hybrid Composites

“…Drug delivery is a hot topic in materials chemistry dealing with the application of different mineral-based supports capable of transporting and releasing drugs. Lerner et al [ 13 ] synthesized a novel bio-hybrid drug delivery system that was based on nitrate intercalated Mg/Al LDH. This allows for the possibility of designing other systems for the sustained release of anionic and neutral drugs.…”

In Situ Synthesis of a Double-Layer Chitosan Coating on Cotton Fabric to Improve the Color Fastness of Sodium Copper Chlorophyllin

“…As alternatives to cationic modification, bio-mordants derived from natural polymer materials have been applied in the textile dyeing [20][21][22]. In recent years, natural polymers, such as chitosan and sodium alginate, have been widely used in antibacterial finishes [23], micro-capsules [24], biocompatible drug delivery [25] and textile dyeing, due to their biocompatibility [26] and friendliness to the environment [27]. Among these bio-mordants, chitosan is a biopolymer derived from the shells of shrimp and crabs [28].…”