Chitosan-Based Particulate Carriers: Structure, Production and Corresponding Controlled Release

On the Structural and Molecular Properties of PEO and PEO-PPG Functionalized Chitosan Nanoparticles for Drug Delivery

Chitosan nanoparticles (CS-NPs) are currently under investigation for a wide range of applications in nanomedicine. We investigated the structural, morphological, and molecular properties of CS-NPs synthesized via ionic gelation and designed specifically for drug delivery. The CS-NPs were prepared at concentrations ranging from 0.25 to 1.0% w/v. The 1.0% w/v CS-NPs were also functionalized with polyethylene oxide (PEO) alone and with a diblock copolymer of PEO and polypropylene glycol (PPG). The average nanoparticle size determined from TEM imaging is in the 11.3 to 14.8 nm range. The XRD and TEM analyses reveal a semi-crystalline structure with a degree of crystallinity dependent upon the nature of CS-NP functionalization. Functionalizing with PEO had no effect, whereas functionalizing with PEO-PPG resulted in a significant increase in the crystallinity of the 1.0% w/v CS-NPs. Additionally, the CS/TPP concentration (CS:TPP fixed at a 1:1 ratio) did not impact the degree of crystallinity of the CS-NPs. FTIR analysis confirmed the incorporation of TPP with CS and an increase in hydrogen bonding in more crystalline CS-NPs.

A review of chitosan nanoparticles: Nature's gift for transforming agriculture through smart and effective delivery mechanisms

Chitosan nanoparticles (CNPs) have emerged as a promising tool in agricultural advancements due to their unique properties including, biocompatability, biodegradability, non-toxicity and remarkable versatility. These inherent properties along with their antimicrobial, antioxidant and eliciting activities enable CNPs to play an important role in increasing agricultural productivity, enhancing nutrient absorption and improving pest management strategies. Furthermore, the nano-formulation of chitosan have the ability to encapsulate various agricultural amendments, enabling the controlled release of pesticides, fertilizers, plant growth promoters and biocontrol agents, thus offering precise and targeted delivery mechanisms for enhanced efficiency. This review provides a comprehensive analysis of the latest research and developments in the use of CNPs for enhancing agricultural practices through smart and effective delivery mechanisms. It discusses the synthesis methods, physicochemical properties, and their role in enhancing seed germination and plant growth, crop protection against biotic and abiotic stresses, improving soil quality and reducing the environmental pollution and delivery of agricultural amendments. Furthermore, the potential environmental benefits and future directions for integrating CNPs into sustainable agricultural systems are explored. This review aims to shed light on the transformative potential of chitosan nanoparticles as nature's gift for revolutionizing agriculture and fostering eco-friendly farming practices.

Chitosan Microparticles Enhance the Intestinal Release and Immune Response of an Immune Stimulant Peptide in Oncorhynchus mykiss

The aquaculture industry is constantly increasing its fish production to provide enough products to maintain fish consumption worldwide. However, the increased production generates susceptibility to infectious diseases that cause losses of millions of dollars to the industry. Conventional treatments are based on antibiotics and antivirals to reduce the incidence of pathogens, but they have disadvantages, such as antibiotic resistance generation, antibiotic residues in fish, and environmental damage. Instead, functional foods with active compounds, especially antimicrobial peptides that allow the generation of prophylaxis against infections, provide an interesting alternative, but protection against gastric degradation is challenging. In this study, we evaluated a new immunomodulatory recombinant peptide, CATH-FLA, which is encapsulated in chitosan microparticles to avoid gastric degradation. The microparticles were prepared using a spray drying method. The peptide release from the microparticles was evaluated at gastric and intestinal pH, both in vitro and in vivo. Finally, the biological activity of the formulation was evaluated by measuring the expression of il-1β, il-8, ifn-γ, Ifn-α, and mx1 in the head kidney and intestinal tissues of rainbow trout (Oncorhynchus mykiss). The results showed that the chitosan microparticles protect the CATH-FLA recombinant peptide from gastric degradation, allowing its release in the intestinal portion of rainbow trout. The microparticle-protected CATH-FLA recombinant peptide increased the expression of il-1β, il-8, ifn-γ, ifn-α, and mx1 in the head kidney and intestine and improved the antiprotease activity in rainbow trout. These results suggest that the chitosan microparticle/CATH-FLA recombinant peptide could be a potential prophylactic alternative to conventional antibiotics for the treatment of infectious diseases in aquaculture.

Extraction, Characterization, and Evaluation of Lepidium sativum Linn. Mucilage as a Mucoadhesive Polymer

Being biocompatible, less toxic, cheap, easily available, and environmentally friendly, there is an increased trust in natural polymers in the drug delivery system. Mucilages, among the natural polymers, are the primary metabolites of plants that have been widely utilized in pharmaceutical manufacturing for different purposes, and mucoadhesive is one among them. The present study was designed to investigate the use of LSM as a mucoadhesive polymer using ibuprofen as a model drug. The mucilage was extracted following an aqueous extraction method and its percentage yield was found to be 13.2% w/w. Besides, three microsphere formulations of ibuprofen were prepared using synthetic polymer hydroxyl propyl methyl cellulose (HPMC) K100M and the LSM in polymer to drug ratios of 1 : 1, 1 : 5, and 3 : 5 by applying ionotropic gelation followed by solvent evaporation methods. The microspheres were evaluated for various micromeritic properties and all the formulations exhibited free-flowing properties. Optical microscopic pictures of almost all the microspheres except F3 and F6 (which had more or less spherical shapes) were found to have irregular and discrete shapes. Besides, the surfaces of all the formulations were rough in texture. The drug entrapment efficiency of the microspheres was found to be between 52.08% ± 0.80 and 87.97% ± 0.72. The in-vitrowash-off test evidenced that almost 50 percent (especially F3) of the microspheres were able to adhere up to 18 h and showed remarkable bioadhesion properties. The in-vitro drug release profile indicated that all the formulations were able to prolong their drug release up to 12 h with a non-fickian release mechanism, except for F4, which followed a fickian release. Therefore, based on the findings of this study, LSM can be used as a potential alternative mucoadhesive excipient for sustained release formulations.