Alginate is a biopolymer used in a variety of biomedical applications due to its favourable properties, such as biocompatibility and non-toxicity. It has been particularly attractive in wound healing applications to date. It can be tailored to materials with properties suitable for wound healing. Alginate has been used to prepare different forms of materials for wound dressings, such as hydrogels, films, wafers, foams, nanofibres, and in topical formulations. The wound dressings prepared from alginate are able to absorb excess wound fluid, maintain a physiologically moist environment, and minimize bacterial infections at the wound site. The therapeutic efficacy of these wound dressings is influenced by the ratio of other polymers used in combination with alginate, the nature of cross linkers used, the time of crosslinking, nature of excipients used, the incorporation of nanoparticles, and antibacterial agents. This review provides a comprehensive overview of the different forms of wound dressings containing alginate, in vitro, and in vivo results.

https://www.mdpi.com/1999-4923/10/2/42/pdf

Alginate in Wound Dressings

Alginate-based composite materials for wound dressing application:A mini review

The dawn of 3D printing in medicals has pinned the domain with hopes of vitality in many patients combating with multitude of diseases. Also entitled as Bio-printing, this is appertained to its sequential printing of precursor ink, embodying cells and polymer/composite, in predetermined trajectory. Precursor ink, in addition to cells, constitutes predominantly hydrogels ascribed to its biodegradability and mimic ability of body's anatomy and mechanical features, e.g. bones, etc. This review paper is devoted to explicate bio-printing (3D/4D) of alginate hydrogels, which are the extract from brown algae, through extrusion additive manufacturing. Alginates are salt derivative of alginic acid and constitute long chain of polysaccharides, which furnishes pliability and gelling adeptness to its structure. Alginate hydrogel (employed for extrusion) can be pristine or composite relying on the requisite properties (target application controlled or in-vivo environment) e.g. Alginate-natural (gelatin/agarose/collagen/hyaluronic acid/etc.) and Alginate-synthetic (polyethylene glycol (PEG)/pluronic F127/etc.). Extrusion additive manufacturing of Alginate is preponderate among others with its uncomplicated processing, material efficiency (cut down on wastage), and outspread adaptability for viscosities (0.03-6*104 Pa.s) but the procedure is limited by resolution(200 ?m) in addition to accuracy. However, 3D-fabricated bio-structures display rigidness (unvarying with conditions) that lacks smart response which is reassured by accounting time feature as noteworthy accessory to printing, interpreting as 4D Bio-printing. This review propounds specific processing itinerary for alginate (meanwhile traversing across its composites/blends with natural and synthetic consideration) in extrusion along with its pre-/during/post-processing parameters intrinsic to process. Furthermore, propensity is also presented in its (Alginate extrusion processing) application for tissue engineering, i.e. bones, cartilage (joints), brain (neural), ear, heart (cardiac), eyes (corneal), etc. due to worldwide quandary over accessibility to natural organs for diverse kinds of diseases. Additionally, the review contemplates recently invented advance printing i.e. 4D printing for biotic species with its challenges and future opportunities.

https://iopscience.iop.org/article/10.1088/1758-5090/ab331e/pdf

Review of alginate-based hydrogel bioprinting for application in tissue engineering.

Alginate hydrogels for bone tissue engineering, from injectables to bioprinting: A review.

Hydrogels are a three-dimensional and crosslinked network of hydrophilic polymers. They can absorb a large amount of water or biological fluids, which leads to their swelling while maintaining their 3D structure without dissolving (Zhu and Marchant, Expert Rev Med Devices 8:607–626, 2011). Among the numerous polymers which have been utilized for the preparation of the hydrogels, polysaccharides have gained more attention in the area of pharmaceutics; Sodium alginate is a non-toxic, biocompatible, and biodegradable polysaccharide with several unique physicochemical properties for which has used as delivery vehicles for drugs (Kumar Giri et al., Curr Drug Deliv 9:539–555, 2012). Owing to their high-water content and resembling the natural soft tissue, hydrogels were studied a lot as a scaffold. The formation of hydrogels can occur by interactions of the anionic alginates with multivalent inorganic cations through a typical ionotropic gelation method. However, those applications require the control of some properties such as mechanical stiffness, swelling, degradation, cell attachment, and binding or release of bioactive molecules by using the chemical or physical modifications of the alginate hydrogel. In the current review, an overview of alginate hydrogels and their properties will be presented as well as the methods of producing alginate hydrogels. In the next section of the present review paper, the application of the alginate hydrogels will be defined as drug delivery vehicles for chemotherapeutic agents. The recent advances in the application of the alginate-based hydrogels will be describe later as a wound dressing and bioink in 3D bioprinting.

/pdf/alginate-based-hydrogels-as-drug-delivery-vehicles-in-cancer-ofytezw246.pdf

Alginate-based hydrogels as drug delivery vehicles in cancer treatment and their applications in wound dressing and 3D bioprinting

Over the last decades, alginates, natural multifunctional polymers, have increasingly drawn attention as attractive compounds in the biomedical and pharmaceutical fields due to their unique physicochemical properties and versatile biological activities. The focus of the paper is to describe biological and pharmacological activity of alginates and to discuss the present use and future possibilities of alginates as a tool in drug formulation. The recent technological advancements with using alginates, issues related to alginates suitability as matrix for three-dimensional tissue cultures, adjuvants of antibiotics, and antiviral agents in cell transplantation in diabetes or neurodegenerative diseases treatment, and an update on the antimicrobial and antiviral therapy of the alginate based drugs are also highlighted.

/pdf/alginate-current-use-and-future-perspectives-in-5b9ql22d3j.pdf

Agata Puciłowska

Papers

Alginate: Current Use and Future Perspectives in Pharmaceutical and Biomedical Applications