Quercetin-loaded alginate microparticles: A contribution on the particle structure

Marine-Derived Polysaccharide Hydrogels as Delivery Platforms for Natural Bioactive Compounds

Marine polysaccharide hydrogels have emerged as an innovative platform for regulating the in vivo release of natural bioactive compounds for medical purposes. These hydrogels, which have exceptional biocompatibility, biodegradability, and high water absorption capacity, create effective matrices for encapsulating different bioactive molecules. In addition, by modifying the physical and chemical properties of marine hydrogels, including cross-linking density, swelling behavior, and response to external stimuli like pH, temperature, or ionic strength, the release profile of encapsulated bioactive compounds is strictly regulated, thus maximizing therapeutic efficacy and minimizing side effects. Finally, by using naturally sourced polysaccharides in hydrogel formulations, sustainability is promoted by reducing dependence on synthetic polymers, meeting the growing demand for eco-friendly materials. This review analyzes the interaction between marine polysaccharide hydrogels and encapsulating compounds and offers examples of how bioactive molecules can be encapsulated, released, and stabilized.

A Systematic Review: Quercetin-Secondary Metabolite of the Flavonol Class, with Multiple Health Benefits and Low Bioavailability

The main goal of this systematic review on the flavonol class secondary metabolite quercetin is to evaluate and summarize the existing research on quercetin's potential health benefits, therapeutic properties, and effectiveness in disease prevention and treatment. In addition to evaluating quercetin's potential for drug development with fewer side effects and lower toxicity, this type of review attempts to collect scientific evidence addressing quercetin's roles as an antioxidant, anti-inflammatory, antibacterial, and anticancer agent. In the first part, we analyze various flavonoid compounds, focusing on their chemical structure, classification, and natural sources. We highlight their most recent biological activities as reported in the literature. Among these compounds, we pay special attention to quercetin, detailing its chemical structure, physicochemical properties, and process of biosynthesis in plants. We also present natural sources of quercetin and emphasize its health benefits, such as its antioxidant and anti-inflammatory effects. Additionally, we discuss methods to enhance its bioavailability, analyzing the latest and most effective delivery systems based on quercetin.

Polysaccharide Based Self-Driven Tubular Micro/Nanomotors as a Comprehensive Platform for Quercetin Loading and Anti-inflammatory Function

Quercetin (QR) is a natural flavonoid with strong anti-inflammatory properties, but it suffers from poor water solubility and bioavailability. Micro/nanomotors (NMs) are tiny devices that convert external energy or chemical fuels into an autonomous motion. They are characterized by their small size, rapid movement, and self-assembly capabilities, which can enhance the delivery of bioactive ingredients. The study synthesized natural polysaccharide-based nanotubes (NTs) using a layer-by-layer self-assembly method and combined with urease (Ure), glucose oxidase (GOx), and Fe3O4 to create three types of NMs. These NMs were well-dispersed and biocompatible. In vitro experiments showed that NMs-Fe3O4 has excellent photothermal conversion properties and potential for use in photothermal therapy. Cellular inflammation model results demonstrated that QR-loaded NMs were not only structurally stable but also improved bioavailability and effectively inhibited the release of inflammatory mediators such as IL-1β and IL-6, providing a safe and advanced carrier system for the effective use of bioactive components in food.

Formulation and Evaluation of Polysaccharide Microparticles for the Controlled Release of Propranolol Hydrochloride

Propranolol hydrochloride, a non-cardio-selective beta blocker, is used to treat several conditions in children, including hypertension, arrhythmias, hyperthyroidism, hemangiomas, etc. Commercial liquid formulations are available in Europe and the US, but they have disadvantages, such as limited stability, bitter taste, and the need for multiple daily doses due to the drug's short half-life. Considering these limitations, controlled-release solid formulations, such as microparticles, may offer a better solution for pediatric administration. The main objective of this study was to formulate an encapsulation system for propranolol hydrochloride, based on sodium alginate and other polysaccharide polymers, to control and prolong its release. Microparticles were prepared using the ionotropic gelation method, which involves instilling a polymer solution into a solution of gelling ions via the extrusion technique. Physicochemical characterization was conducted by assessing the entrapment efficiency, drug loading, swelling index, microparticle size, rheological properties, and surface tension. In order to improve the characteristics of the tested microparticles, selected formulations were coated with chitosan. Further experimental work included differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) analysis, and SEM imaging. This in vitro release study showed that chitosan-coated microparticles demonstrate favorable properties, suggesting a novel approach to formulating pediatric dosage forms, although further optimization is necessary.

Synthesis and bioactivity assessment of Coccinia grandis L. extract encapsulated alginate nanoparticles as an antidiabetic drug lead

AIM

This study aimed to prepare, characterise, and evaluate the antidiabetic activity of Coccinia grandis (L.) extracts encapsulated alginate nanoparticles.

METHODS

Alginate nanoparticles were prepared using the ionic gelation method and characterised by encapsulation efficiency %w/w, loading capacity %w/w, particle size analysis, zeta potential, Fourier transform infra-red spectroscopy (FTIR), and scanning electron microscopy (SEM). In vitro antidiabetic activity was also evaluated.

RESULTS

Encapsulation efficiency %w/w, loading capacity %w/w, mean diameter, zeta potential of C. grandis encapsulated alginate nanoparticles ranged from 10.51 ± 0.51 to 62.01 ± 1.28%w/w, 0.39 ± 0.04 to 3.12 ± 0.11%w/w, 191.9 ± 76.7 to 298.9 ± 89.6 nm, -21.3 ± 3.3 to -28.4 ± 3.4 mV, respectively. SEM and FTIR confirmed that particles were in nano range with spherical shape and successful encapsulation of plant extracts into an alginate matrix. The antidiabetic potential of aqueous extract of C. grandis encapsulated alginate nanoparticles (AqCG-ANP) exhibited inhibition in α-amylase, α-glucosidase and dipeptidyl peptidase IV enzymes of 60.8%c/c, 19.1%c/c, and 30.3%c/c, respectively, compared to the AqCG.

CONCLUSION

The AqCG-ANP exerted promising antidiabetic potential as an antidiabetic drug lead.

A Bioengineered Quercetin-Loaded 3D Bio-Polymeric Graft for Tissue Regeneration and Repair

Phytochemicals extracted from plant sources have potential remedial effects to cure a broad range of acute to severe illnesses and ailments. Quercetin is a flavonoid isolated from different dietary sources such as vegetables and fruits, exhibiting strong anti-inflammatory, anti-oxidative and non-toxic effects on the biological system. However, the direct uptake or administration of quercetin results in loss of functionality, poor activity, and reduced shelf-life of the bioactive component. In this regard, to improve the uptake, potential, and efficiency of natural components with prolonged storage in the host's body after administration, numerous polymer drug delivery systems have been created. In the current study, three-dimensional (3D) porous (porosity: 92%; pore size: 81 µm) bio-polymeric foaming gelatin-alginate (GA) beads were fabricated for the entrapment of quercetin as therapeutic drug molecules-gelatin-alginate-quercetin (GAQ). The GAQ beads showed a significant uptake of quercetin molecules resulting in a reduction of reduced porosity up to 64% and pore size 63 µm with a controlled release profile in the PBS medium, showing ~80% release within 24 h. Subsequently, the GAQ beads showed remarkable antioxidant effects, and 95% anti-inflammatory activities along with remarkable in vitro cell culture growth and the observed proliferation of seeded fibroblast cells. Thus, we can conclude that the consistent release of quercetin showed non-toxic effects on normal cell lines and the bioactive surface of the GAQ beads enhances cell adhesion, proliferation, and differentiation more effectively than control GA polymeric beads and tissue culture plates (TCP). In summary, these findings show that these GAQ beads act as a biocompatible 3D construct with enormous potential in medicinal administration and tissue regeneration for accelerated healing.

Preparation and Characterization of Chitosan-Alginate Microspheres Loaded with Quercetin

The aim of this paper was to formulate microspheres based on biodegradable polymers (chitosan and sodium alginate), using the complex coacervation technique. Subsequently, the prepared microspheres were loaded with quercetin (QUE), a pharmacological active ingredient insoluble in water and unstable to light, temperature and air. After preparation, the loaded microspheres underwent several studies for physical chemical characterization (performed by scanning electron microscopy-SEM, laser 3D scanning, and thermal analysis-TA). Furthermore, they were analyzed in order to obtain information regarding swelling index, drug entrapment, and in vitro release capacity. The obtained experimental data demonstrated 86.07% entrapment of QUE into the microspheres, in the case of the one with the highest Ch concentration. Additionally, it was proved that such systems allow the controlled release of the active drug over 24 h at the intestinal level. SEM micrographs proved that the prepared microspheres have a wrinkled surface, with compact structures and a large number of folds. On the basis of the TA analysis, it was concluded that the obtained microspheres were thermally stable, facilitating their usage at normal physiological temperatures as drug delivery systems.

Freeze-Dried Matrices Composed of Degradable Polymers with Surfactant-Loaded Microparticles Based on Pectin and Sodium Alginate

Gelatin/polyvinylpyrrolidone/hydroxyethyl cellulose/glycerol porous matrices with microspheres made of sodium alginate or pectin and sodium alginate were produced. A surfactant was loaded into these microparticles. The microspheres were characterized using optical microscopy, scanning electron microscopy SEM, and laser diffraction particle size analyzer. For the matrices, the density, porosity, swelling capacity, dissolution in phosphate saline buffer were determined and SEM, mechanical, and thermogravimetric studies were applied. The results showed that the size of the two-component microspheres was slightly larger than that of single-ingredient microparticles. The images confirmed the spherical shape of the microparticles. The prepared matrices had high water uptake ability and porosity due to the presence of hydrophilic polymers. The presence of microparticles in the matrices caused a decrease in these parameters. Degradation of the composites with the microspheres was significantly faster than the matrix without them. The addition of microparticles increased the stiffness and toughness of the prepared materials. The efficiency of the thermal decomposition main stage was reduced in the samples with microspheres, whereas a char residue increased in these composites.