Efficient epidermal delivery of antibiotics by self-assembled lecithin/chitosan nanoparticles for enhanced therapy on epidermal bacterial infections

Antibacterial Lecithin/Chitosan Nanoparticles for the Sustained Release of Ciprofloxacin to Treat Ocular Bacterial Infections

Ocular drug-delivery is one of the most challenging areas owing to nature of ocular tissues. Various nanoformulations have been designed and investigated for drug-delivery to achieve high drug bioavailability. The major focus of these preparations available in market is to utilize nanomaterial as drug-carrier only, with less focus on developing functional-nanomaterials, which is a key knowledge gap in the field. To address this, we developed a nanoparticulate system from bioactive-polymers, having intrinsic antimicrobial and mucoadhesiveness, loaded with ciprofloxacin (cipro) to treat ocular bacterial infections. Cipro-loaded lecithin/chitosan nanoparticles were prepared and characterized for their physiochemical properties. They exhibited good drug loading efficiency and showed sustained drug-release for 72 h, with slow release for first 4 h followed by a burst release in phosphate buffered saline and simulated tear fluid. Cipro-loaded nanoparticles were assessed for their antibacterial potential against Staphylococcus aureus (96 %) and Pseudomonas aeruginosa (72 %) using optical density, disc-diffusion method, live-dead assay, and demonstrated promising antibacterial properties. The drug-loaded nanoparticles showed good cytocompatibility (~90 %) towards murine fibroblasts and rabbit corneal cells. Being amphiphilic in nature, the nanoparticles exhibited mucoadhesiveness, hemocompatibility (<4 %) and, thus, proving to be a promising candidate for treating ocular infections. This approach ensures efficient drug delivery and synergic/additive therapeutic effects.

All-aqueous microfluidic fabrication of calcium alginate/alkylated chitosan core-shell microparticles with time-sequential functions for promoting whole-stage wound healing

Wound healing comprises a series of complex physiological processes, including hemostasis, inflammation, cell proliferation, and tissue remodeling. Designing new functional biomaterials by biological macromolecules with tailored therapeutic effects to precisely match the unique requirements of each stage is cherished but rarely discussed. Here, we employ all-aqueous microfluidics to fabricate multifunctional core-shell microparticles aimed at promoting whole-stage wound healing. These microparticles feature a core comprising calcium alginate, cellulose nanocrystals and epidermal growth factor, surrounded by a shell made of alkylated chitosan, alginate, and ciprofloxacin (EGF + CNC@Ca-ALG/CIP@ACS core-shell microparticles, D-CSMP). Response surface methodology (RSM) with a combination of central composite rotatable design (CCRD) is used to meticulously optimize the fabrication processes, endowing the resulting D-CSMP with superior capabilities for efficiently encapsulating and controlled releasing CIP and EGF tailored to each stage aligning the healing timeline. The developed D-CSMP demonstrate notable time-sequential functionalities, including promoting blood coagulation, enhancing hemostasis, and exerting antibacterial effects. Furthermore, in a skin injury model, D-CSMP significantly expedite and enhance the chronic wound healing process. In conclusion, our core-shell microparticles with notable time-sequential functions present a versatile and robust approach for wound treatment and related biomedical applications.

Robust and Wet Adhesive Self-Gelling Powders for Rapid Hemostasis and Efficient Wound Healing

Healing traumatic wounds is arduous, leaving miscellaneous demands for ideal wound dressings, such as rapid hemostasis, superior wet tissue adhesion, strong mechanical properties, and excellent antibacterial activity. Herein, we report a self-gelling, wet adhesive, stretchable (polyethylenimine/poly(dimethylammonium chloride)/(poly(acrylic acid)/poly(sodium styrenesulfonate)/alkylated chitosan)) ((PEI/PDDA)/(PAA/PSS)/ACS) powder as a new option. The self-gel utilizes noncovalent interactions among in situ formed PDDA/PSS nanoparticles and PEI/PAA polymetric matrices to earn sensational mechanical properties and tensile strength while incorporating ACS to obtain fast hemostasis and therapeutic capacities. The powder can form a hydrogel patch in situ within 3 s upon liquid absorption, capable of resisting pressure higher than twice the blood pressure. Deposition of the self-gelling powders on various wounds, such as rat liver and femoral artery wounds, can stop bleeding in 10 s and lessen the amount of bleeding 6-fold plus in corresponding models. Furthermore, the self-gelling powders can significantly advance the chronic wound healing process by displaying a high wound healing rate and a low inflammatory response and promoting the formation of new blood vessels and tissue regeneration. The satisfactory mechanical properties, strong wet adhesion, sufficient antibacterial properties, ease of usage, adaptability to complex wounds, rapid hemostasis, and superior therapeutic capacities of (PEI/PDDA)/(PAA/PSS)/ACS self-gelling powders render them as a profound wound dressing biomaterial.

Chitosan nanoparticles and based composites as a biocompatible vehicle for drug delivery: A review

The shellfish processing industry is one of the largest growing industries across the globe with a market size of around USD 62B. However, it also leads to a significant environmental issue as it produces >80,000 tons of waste shells globally. Unfortunately, the slow degradation of this waste causes it to accumulate over time, posing a serious threat to the marine environment. The key solution to this problem is to recycle this sea waste into a valuable product like chitin which is further used to produce chitosan. Chitosan is a natural biopolymeric substance obtained via N-deacetylation of the chitin. The chitosan-based nanoparticles are further useful for the fabrication of biopolymeric nanocomposites which are used in various biomedical applications specifically in drug delivery. Here, we review the recent advancements in the development of chitosan-based nanocomposites as a biocompatible carrier for drug delivery, specifically focusing on gene delivery, wound healing, microbial treatment, and anticancer drug delivery. By providing a valuable and up-to-date resource, this review illuminates the current state of research concerning chitosan's pivotal role in the biomedical domain as an efficacious drug delivery agent.

Strategies for the Preparation of Chitosan Derivatives for Antimicrobial, Drug Delivery, and Agricultural Applications: A Review

Chitosan has received much attention for its role in designing and developing novel derivatives as well as its applications across a broad spectrum of biological and physiological activities, owing to its desirable characteristics such as being biodegradable, being a biopolymer, and its overall eco-friendliness. The main objective of this review is to explore the recent chemical modifications of chitosan that have been achieved through various synthetic methods. These chitosan derivatives are categorized based on their synthetic pathways or the presence of common functional groups, which include alkylated, acylated, Schiff base, quaternary ammonia, guanidine, and heterocyclic rings. We have also described the recent applications of chitosan and its derivatives, along with nanomaterials, their mechanisms, and prospective challenges, especially in areas such as antimicrobial activities, targeted drug delivery for various diseases, and plant agricultural domains. The accumulation of these recent findings has the potential to offer insight not only into innovative approaches for the preparation of chitosan derivatives but also into their diverse applications. These insights may spark novel ideas for drug development or drug carriers, particularly in the antimicrobial, medicinal, and plant agricultural fields.

Functional nano-systems for transdermal drug delivery and skin therapy

Transdermal drug delivery is one of the least intrusive and patient-friendly ways for therapeutic agent administration. Recently, functional nano-systems have been demonstrated as one of the most promising strategies to treat skin diseases by improving drug penetration across the skin barrier and achieving therapeutically effective drug concentrations in the target cutaneous tissues. Here, a brief review of functional nano-systems for promoting transdermal drug delivery is presented. The fundamentals of transdermal delivery, including skin biology and penetration routes, are introduced. The characteristics of functional nano-systems for facilitating transdermal drug delivery are elucidated. Moreover, the fabrication of various types of functional transdermal nano-systems is systematically presented. Multiple techniques for evaluating the transdermal capacities of nano-systems are illustrated. Finally, the advances in the applications of functional transdermal nano-systems for treating different skin diseases are summarized.