The binary complex of poly(PEGMA-co-MAA) hydrogel and PLGA nanoparticles as a novel oral drug delivery system for ibuprofen delivery

Preparation of new hydrogels by visible light cross-linking of dextran methacrylate and poly(ethylene glycol)-maleic acid copolymer

In this work, a series of new biodegradable and biocompatible hydrogels were synthesized by photopolymerization of dextran-methacrylate (DXM) with poly(ethylene glycol)-maleic acid copolymer (poly(PEG-co-MA, PEGMA)) using (-)-riboflavin as a visible light photoinitiator and L-arginine as a co-photoinitiator. DXM was prepared by acylation of dextran (DX) with methacryloyl chloride (MAC), and PEGMA was synthesized by polycondensation of poly(ethylene glycol) (PEG) and maleic acid (MA). The DXM and PEGMA were characterized by FT-IR and ¹HNMR spectroscopy. Different types of hydrogels from various ratios of DXM and PEGMA were prepared and characterized by SEM. The results showed that the prepared hydrogel by photo-cross-linking of DXM (DPHG0) was transparent and flexible, and its physical shape was excellent, but it was sticky. The stickiness was reduced by increasing the PEGMA contents, and different types of DXM/PEGMA hydrogels (DPHG1-4) with various properties were prepared. For example, DPHG2 (PEGMA content was 0.25 g) was transparent and flexible, its physical shape was excellent, and it was not sticky. The prepared hydrogels showed excellent cytocompatibility, and their tensile and compressive strength were also evaluated. Additionally, the in vitro degradation and swelling ratios of the prepared hydrogels were studied in buffer solution at different pHs.

Fabrication of CaCO3-Coated Vesicles by Biomineralization and Their Application as Carriers of Drug Delivery Systems

We fabricated CaCO3-coated vesicles as drug carriers that release their cargo under a weakly acidic condition. We designed and synthesized a peptide lipid containing the Val-His-Val-Glu-Val-Ser sequence as the hydrophilic part, and with two palmitoyl groups at the N-terminal as the anchor groups of the lipid bilayer membrane. Vesicles embedded with the peptide lipids were prepared. The CaCO3 coating of the vesicle surface was performed by the mineralization induced by the embedded peptide lipid. The peptide lipid produced the mineral source, CO32-, for CaCO3 mineralization through the hydrolysis of urea. We investigated the structure of the obtained CaCO3-coated vesicles using transmission electron microscopy (TEM). The vesicles retained the spherical shapes, even in vacuo. Furthermore, the vesicles had inner spaces that acted as the drug cargo, as observed by the TEM tomographic analysis. The thickness of the CaCO3 shell was estimated as ca. 20 nm. CaCO3-coated vesicles containing hydrophobic or hydrophilic drugs were prepared, and the drug release properties were examined under various pH conditions. The mineralized CaCO3 shell of the vesicle surface was dissolved under a weakly acidic condition, pH 6.0, such as in the neighborhood of cancer tissues. The degradation of the CaCO3 shell induced an effective release of the drugs. Such behavior suggests potential of the CaCO3-coated vesicles as carriers for cancer therapies.

Influence of spray-drying process on properties of chitosan/xanthan gum polyelectrolyte complexes as carriers for oral delivery of ibuprofen

Polyelectrolyte complexes (PECs) are attractive carriers with recognized potential to enhance oral delivery of poorly soluble high-dosed low-molecular-weight drugs. The formulation of solid oral dosage forms requires the drying of PECs, which may affect their physicochemical and biopharmaceutical properties. The aim of this study was to investigate the effect of spraydrying on the properties of ibuprofen-loaded chitosan/xanthan gum PECs and to assess the drug release kinetics from such PECs filled into hard capsules in comparison with corresponding PECs which are dried under ambient conditions. The yield, ibuprofen content, entrapment efficiency, and residual moisture content of spray-dried PECs were lower than those of ambient-dried PECs. Better flowability of spray-dried PECs was attributed to the almost spherical particle shape, shown by scanning electron microscopy. DSC and PXRD analysis confirmed the amorphization of ibuprofen during spray-drying. All the investigated PECs, obtained by drying under ambient conditions as well as by spray-drying, had high rehydration capacity both in 0.1 M hydrochloric acid (pH 1.2) and phosphate buffer pH 7.4. In vitro ibuprofen release from dried PECs was controlled during 12 h with the release of approximately 30% of entrapped ibuprofen. Spray-dried PECs provided better control of ibuprofen diffusion from the carrier compared to the ambientdried ones.

Advanced nanomedicines for the treatment of inflammatory diseases

Inflammation, a common feature of many diseases, is an essential immune response that enables survival and maintains tissue homeostasis. However, in some conditions, the inflammatory process becomes detrimental, contributing to the pathogenesis of a disease. Targeting inflammation by using nanomedicines (i.e. nanoparticles loaded with a therapeutic active principle), either through the recognition of molecules overexpressed onto the surface of activated macrophages or endothelial cells, or through enhanced vasculature permeability, or even through biomimicry, offers a promising solution for the treatment of inflammatory diseases. After providing a brief insight on the pathophysiology of inflammation and current therapeutic strategies, the review will discuss, at a pre-clinical stage, the main innovative nanomedicine approaches that have been proposed in the past five years for the resolution of inflammatory disorders, finally focusing on those currently in clinical trials.

A facile method to fabricate thermo- and pH-sensitive hydrogels with good mechanical performance based on poly(ethylene glycol) methyl ether methacrylate and acrylic acid as a potential drug carriers

A thermo- and pH-sensitive hydrogel was prepared by a facile free aqueous radical copolymerization of PEGMA and AAc without any crosslinkers for controlled drug delivery. The successful fabrication of hydrogels was confirmed by Fourier transform infrared spectroscopy (FT-IR) and thermo gravimetric analysis (TGA) measurements. The morphological, mechanical and swelling properties of the obtained hydrogels were studied systematically. The results showed that the morphological and mechanical behaviors of the resultant hydrogels were strongly affected by the content of AAc. Moreover, the obtained hydrogels showed an excellent thermo-, pH- and salinity sensitivities. Release profiles of 5-Fu were studied at different pH (gastric pH 1.2 and intestinal pH 7.4) and temperatures (25 °C and 37 °C). The results showed that the release is very low at pH 1.2/37 °C and high at pH 7.4/25 °C. The cytotoxicity of hydrogels to cells was determined by an MTT assay. The result demonstrated that the blank hydrogels had negligible toxicity to cells, whereas the 5-Fu-loaded hydrogels remained high in cytotoxicity for LO2 and HepG-2 cells. Results of the present investigation exemplify the potential of this novel thermo- and pH-sensitive hydrogel for the controlled and targeted delivery of the anti cancer drug 5-Fu.

Investigation of the blends of chitosan and tragacanth as potential drug carriers for the delivery of ibuprofen in the intestine

This study provides a new potential hydrogel for the intestinal delivery of ibuprofen.

Formulation and delivery strategies of ibuprofen: challenges and opportunities

Ibuprofen, a non-steroidal anti-inflammatory drug (NSAID), is mostly administered orally and topically to relieve acute pain and fever. Due to its mode of action this drug may be useful in the treatment regimens of other, more chronic conditions, like cystic fibrosis. This drug is poorly soluble in aqueous media and thus the rate of dissolution from the currently available solid dosage forms is limited. This leads to poor bioavailability at high doses after oral administration, thereby increasing the risk of unwanted adverse effects. The poor solubility is a problem for developing injectable solution dosage forms. Because of its poor skin permeability, it is difficult to obtain an effective therapeutic concentration from topical preparations. This review aims to give a brief insight into the status of ibuprofen dosage forms and their limitations, particle/crystallization technologies for improving formulation strategies as well as suggesting its incorporation into the pulmonary drug delivery systems for achieving better therapeutic action at low dose.