The aim of the present work is fabrication of dual cross linked sodium alginate (SA)/montmorillonite (MMT) microbeads as a potential drug vehicle for extended release of curcumin (CUR). The microbeads were prepared using in situ ion-exchange followed by simple ionotropic gelation technique. The developed beads were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (X-RD) and scanning electron microscopy (SEM). The effect of MMT on encapsulation efficiency of CUR and intercalation kinetics was investigated. Dynamic swelling study and in vitro release study were investigated in simulated intestinal fluid (pH 7.4) and simulated gastric fluid (pH 1.2) at 37 °C. Results suggested that both the swelling and in vitro release studies were influenced by the pH of test media, which might be suitable for intestinal drug delivery. The release mechanism was analyzed by fitting the release data into Korsmeyer-Peppas equation.

Nanogels have high tunability and stability while being able to sense and respond to external stimuli by showing changes in the gel volume, water content, colloidal stability, mechanical strength, and other physical/chemical properties. In this article, advances in the preparation of nanogels will be reviewed. The application potential of nanogels in drug delivery will also be highlighted. It is the objective of this article to present a snapshot of the recent knowledge of nanogel preparation and application for future research in drug delivery.

The development of combination therapy has received great attention in recent years because of its potential to achieve higher therapeutic efficacy than that achieved by mono-drug therapy. Carriers for effective and stimuli-responsive co-delivery of multiple agents, however, are highly deficient at the moment. To address this need, this study reports the generation of multi-component hydrogel beads incorporated with reduced graphene oxide (rGO). The beads are prepared by incorporating doxorubicin (DOX)-loaded gelatine (GL) microbeads into hydrogel beads containing rGO and 5-fluorouracil (5-FU). rGO-containing beads are shown to be more effective in inhibiting the growth of MCF-7 cells via the induction of reactive oxygen species (ROS) generation. In addition, the drug release sustainability of the beads is affected by the pH of the release medium, with the release rate increasing in neutral pH but decreasing in the acidic environment. Our beads warrant further development as carriers for pH-responsive and controlled co-delivery of multiple agents.

Purpose: Magnetic nanoparticles have been used in diverse pharmaceutical applications because they can potentially be used to target specific sites. In the present work, a new type of nanocomposites is designed as a carrier of controlled bioactive agent delivery. Methods: Amine-functionalized magnetic nanoparticles (amine-MNPs) are coupled with carboxymethyl chitosan (CMC) to generate the nanocomposites, namely MNPs-CMC, which can be further loaded with doxorubicin (DOX) to produce MNPs-CMC-DOX. The generated nanocomposites are characterized by using various techniques (including FTIR, ¹H-NMR, DSC, TGA, SEM, TEM and XRD). In vitro drug release studies are conducted in PBS with different pH values (1.2 and 6.8) at different temperatures (25°C and 37°C). The toxicity of the nanocomposites is tested in MCF-7 and 3T3 cells. The ROS-generating capacity of the nanocomposites is determined in treated cells using 2’,7’-dichlorodihydrofluorescein diacetate. Results: The structures of MNPs, CMC, and nanocomposites are confirmed by FTIR, XRD, and ¹H-NMR data reveals the formation of CMC from chitosan (CS). The size of MNPs is estimated by TEM to be around 25 nm. After conjugation with CMC, the size of the nanocomposites increases to 46– 57 nm. Based on the release profiles of MNPs-CMC-DOX, our nanocomposites are pH-responsive. In addition, our nanocomposites show reactive oxygen species (ROS)-generating capacity and cell type-dependent toxicity. Conclusion: Our nanocomposites show high potential for use in bioactive agent delivery. Along with their ROS-generating capacity, they warrant further development as pH-responsive carriers for therapeutic applications.

The present study reports the generation of 2-hydroxyethyl starch microparticles for co-delivery and controlled release of multiple agents. The obtained microparticles are characterized by using Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction analysis, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. By using ofloxacin and ketoprofen as drug models, the release sustainability of the microparticles is examined at pH 1.2, 5.4, and 6.8 at 37 °C, with Fickian diffusion being found to be the major mechanism controlling the kinetics of drug release. Upon being loaded with the drug models, the microparticles show high efficiency in acting against Escherichia coli and Bacillus cereus. The results suggest that our reported microparticles warrant further development for applications in which co-administration of multiple bioactive agents is required.