Chitosan: A Versatile Polymer for 21st Century

Chitosan arouses large interest due to its properties and possible applications. Every year the number of publications and patents based on this polymer increases. Chitosan exhibits poor solubility in neutral and basic media limiting its use in such conditions. Another serious obstacle is directly related to its natural origin. Chitosan is not a single polymer with a defined structure but a family of molecules with differences in their composition, size, and monomer distribution. These properties have a fundamental effect on the biological and technological performance of the polymer. Moreover, some of the biological properties claimed are discrete. In this review, we discuss how chitosan chemistry can solve the problems related to its poor solubility and can boost the polymer properties. We focus on some of the main biological properties of chitosan and the relationship with the physicochemical properties of the polymer. Then, we visit two polymer applications related to green processes: the use of chitosan in the green synthesis of metallic na-noparticles and its use as support in biocatalyst. Finally, we briefly describe how making use of the technological properties of chitosan it is possible to develop a variety of systems for drug delivery

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Chitosan: An Overview of Its Properties and Applications

Polymers ◽

10.3390/polym13193256 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3256

Author(s):

Inmaculada Aranaz ◽

Andrés R. Alcántara ◽

Maria Concepción Civera ◽

Concepción Arias ◽

Begoña Elorza ◽

...

Keyword(s):

Metallic Nanoparticles ◽

Biological Properties ◽

Technological Properties ◽

Natural Origin ◽

Technological Performance ◽

Poor Solubility ◽

Polymer Properties ◽

Monomer Distribution ◽

Number Of Publications ◽

The Relationship

Chitosan has garnered much interest due to its properties and possible applications. Every year the number of publications and patents based on this polymer increase. Chitosan exhibits poor solubility in neutral and basic media, limiting its use in such conditions. Another serious obstacle is directly related to its natural origin. Chitosan is not a single polymer with a defined structure but a family of molecules with differences in their composition, size, and monomer distribution. These properties have a fundamental effect on the biological and technological performance of the polymer. Moreover, some of the biological properties claimed are discrete. In this review, we discuss how chitosan chemistry can solve the problems related to its poor solubility and can boost the polymer properties. We focus on some of the main biological properties of chitosan and the relationship with the physicochemical properties of the polymer. Then, we review two polymer applications related to green processes: the use of chitosan in the green synthesis of metallic nanoparticles and its use as support for biocatalysts. Finally, we briefly describe how making use of the technological properties of chitosan makes it possible to develop a variety of systems for drug delivery.

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Nano- and Microcarriers as Drug Delivery Systems for Usnic Acid: Review of Literature

Pharmaceutics ◽

10.3390/pharmaceutics12020156 ◽

2020 ◽

Vol 12 (2) ◽

pp. 156 ◽

Cited By ~ 4

Author(s):

Ana Zugic ◽

Vanja Tadic ◽

Snezana Savic

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Usnic Acid ◽

Chemical Properties ◽

Biological Properties ◽

Delivery Systems ◽

Physico Chemical ◽

Wide Range ◽

Number Of Publications ◽

Promising Therapeutic Agent

Usnic acid is one of the most investigated lichen secondary metabolites, with several proven biological properties with potential medical relevance. However, its unfavorable physico-chemical properties, as well as observed hepatotoxicity, have discouraged wide-range utilization of usnic acid as a promising therapeutic agent. In accordance with the growing research interest in the development of nanotechnology, especially in the arena of preparations based on natural sources of medicinal compounds, usnic acid incorporated into nano- and microsized colloidal carriers has been a subject of a large number of publications. Therefore, this review discusses the overall results of the studies dealing with usnic acid encapsulated into lipid-based, polymeric and nonorganic micro- and/or nanocarriers, as potential drug delivery systems for this natural compound, in an attempt to introduce its usage as a potential antitumor, antimicrobial, wound-healing, antioxidative and anti-inflammatory drug.

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Design and Assessment of Biodegradable Macroporous Cryogels as Advanced Tissue Engineering and Drug Carrying Materials

Gels ◽

10.3390/gels7030079 ◽

2021 ◽

Vol 7 (3) ◽

pp. 79

Author(s):

Irina N. Savina ◽

Mohamed Zoughaib ◽

Abdulla A. Yergeshov

Keyword(s):

Drug Delivery ◽

Tissue Engineering ◽

Biomedical Applications ◽

Biological Properties ◽

Gelation Process ◽

Biological Environment ◽

Advanced Biomaterials ◽

The Relationship ◽

Interconnected Pores ◽

Selection Of

Cryogels obtained by the cryotropic gelation process are macroporous hydrogels with a well-developed system of interconnected pores and shape memory. There have been significant recent advancements in our understanding of the cryotropic gelation process, and in the relationship between components, their structure and the application of the cryogels obtained. As cryogels are one of the most promising hydrogel-based biomaterials, and this field has been advancing rapidly, this review focuses on the design of biodegradable cryogels as advanced biomaterials for drug delivery and tissue engineering. The selection of a biodegradable polymer is key to the development of modern biomaterials that mimic the biological environment and the properties of artificial tissue, and are at the same time capable of being safely degraded/metabolized without any side effects. The range of biodegradable polymers utilized for cryogel formation is overviewed, including biopolymers, synthetic polymers, polymer blends, and composites. The paper discusses a cryotropic gelation method as a tool for synthesis of hydrogel materials with large, interconnected pores and mechanical, physical, chemical and biological properties, adapted for targeted biomedical applications. The effect of the composition, cross-linker, freezing conditions, and the nature of the polymer on the morphology, mechanical properties and biodegradation of cryogels is discussed. The biodegradation of cryogels and its dependence on their production and composition is overviewed. Selected representative biomedical applications demonstrate how cryogel-based materials have been used in drug delivery, tissue engineering, regenerative medicine, cancer research, and sensing.

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Work Engagement and Research Output Among Female and Male Scientists

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000150 ◽

2016 ◽

Vol 15 (2) ◽

pp. 55-65 ◽

Cited By ~ 4

Author(s):

Lonneke Dubbelt ◽

Sonja Rispens ◽

Evangelia Demerouti

Keyword(s):

Work Engagement ◽

Research Output ◽

Research Performance ◽

Daily Work ◽

Time Control ◽

Science Technology ◽

And Performance ◽

And Mathematics ◽

Number Of Publications ◽

The Relationship

Abstract. Women have a minority position within science, technology, engineering, and mathematics and, consequently, are likely to face more adversities at work. This diary study takes a look at a facilitating factor for women’s research performance within academia: daily work engagement. We examined the moderating effect of gender on the relationship between two behaviors (i.e., daily networking and time control) and daily work engagement, as well as its effect on the relationship between daily work engagement and performance measures (i.e., number of publications). Results suggest that daily networking and time control cultivate men’s work engagement, but daily work engagement is beneficial for the number of publications of women. The findings highlight the importance of work engagement in facilitating the performance of women in minority positions.

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Polymeric Nanoparticles for Brain Drug Delivery - A Review

Current Drug Metabolism ◽

10.2174/1389200221666200508074348 ◽

2020 ◽

Vol 21 (9) ◽

pp. 649-660

Author(s):

Subashini Raman ◽

Syed Mahmood ◽

Ayah R. Hilles ◽

Md Noushad Javed ◽

Motia Azmana ◽

...

Keyword(s):

Drug Delivery ◽

Surface Modification ◽

Polymeric Nanoparticles ◽

Drug Loading ◽

Preparation Methods ◽

Brain Drug Delivery ◽

Polymeric Nanoparticle ◽

Relationship Of ◽

The Relationship ◽

The Brain

Background: Blood-brain barrier (BBB) plays a most hindering role in drug delivery to the brain. Recent research comes out with the nanoparticles approach, is continuously working towards improving the delivery to the brain. Currently, polymeric nanoparticle is extensively involved in many therapies for spatial and temporal targeted areas delivery. Methods: We did a non-systematic review, and the literature was searched in Google, Science Direct and PubMed. An overview is provided for the formulation of polymeric nanoparticles using different methods, effect of surface modification on the nanoparticle properties with types of polymeric nanoparticles and preparation methods. An account of different nanomedicine employed with therapeutic agent to cross the BBB alone with biodistribution of the drugs. Results: We found that various types of polymeric nanoparticle systems are available and they prosper in delivering the therapeutic amount of the drug to the targeted area. The effect of physicochemical properties on nanoformulation includes change in their size, shape, elasticity, surface charge and hydrophobicity. Surface modification of polymers or nanocarriers is also vital in the formulation of nanoparticles to enhance targeting efficiency to the brain. Conclusion: More standardized methods for the preparation of nanoparticles and to assess the relationship of surface modification on drug delivery. While the preparation and its output like drug loading, particle size, and charge, permeation is always conflicted, so it requires more attention for the acceptance of nanoparticles for brain delivery.

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Biodistribution and Pharmacokinectics of Liposomes and Exosomes in a Mouse Model of Sepsis

Pharmaceutics ◽

10.3390/pharmaceutics13030427 ◽

2021 ◽

Vol 13 (3) ◽

pp. 427

Author(s):

Amin Mirzaaghasi ◽

Yunho Han ◽

So-Hee Ahn ◽

Chulhee Choi ◽

Ji-Ho Park

Keyword(s):

Drug Delivery ◽

Therapeutic Potential ◽

Hek293t Cell ◽

Biological Properties ◽

Context Analysis ◽

Drug Delivery Vehicles ◽

Delivery Vehicles ◽

Diseased State ◽

Sepsis And Septic Shock

Exosomes have attracted considerable attention as drug delivery vehicles because their biological properties can be utilized for selective delivery of therapeutic cargoes to disease sites. In this context, analysis of the in vivo behaviors of exosomes in a diseased state is required to maximize their therapeutic potential as drug delivery vehicles. In this study, we investigated biodistribution and pharmacokinetics of HEK293T cell-derived exosomes and PEGylated liposomes, their synthetic counterparts, into healthy and sepsis mice. We found that biodistribution and pharmacokinetics of exosomes were significantly affected by pathophysiological conditions of sepsis compared to those of liposomes. In the sepsis mice, a substantial number of exosomes were found in the lung after intravenous injection, and their prolonged blood residence was observed due to the liver dysfunction. However, liposomes did not show such sepsis-specific effects significantly. These results demonstrate that exosome-based therapeutics can be developed to manage sepsis and septic shock by virtue of their sepsis-specific in vivo behaviors.

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Antiviral Activity of Carrageenans and Processing Implications

Marine Drugs ◽

10.3390/md19080437 ◽

2021 ◽

Vol 19 (8) ◽

pp. 437

Author(s):

Milena Álvarez-Viñas ◽

Sandra Souto ◽

Noelia Flórez-Fernández ◽

Maria Dolores Torres ◽

Isabel Bandín ◽

...

Keyword(s):

Drug Delivery ◽

Antiviral Activity ◽

Drug Delivery Systems ◽

Biological Properties ◽

Red Seaweed ◽

Processing Conditions ◽

Chemical Modifications ◽

Viral Attachment ◽

Extraction Stage ◽

Composition Structure

Carrageenan and carrageenan oligosaccharides are red seaweed sulfated carbohydrates with well-known antiviral properties, mainly through the blocking of the viral attachment stage. They also exhibit other interesting biological properties and can be used to prepare different drug delivery systems for controlled administration. The most active forms are λ-, ι-, and κ-carrageenans, the degree and sulfation position being determined in their properties. They can be obtained from sustainable worldwide available resources and the influence of manufacturing on composition, structure, and antiviral properties should be considered. This review presents a survey of the antiviral properties of carrageenan in relation to the processing conditions, particularly those assisted by intensification technologies during the extraction stage, and discusses the possibility of further chemical modifications.

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Tocopherols and Tocotrienols—Bioactive Dietary Compounds; What Is Certain, What Is Doubt?

International Journal of Molecular Sciences ◽

10.3390/ijms22126222 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6222

Author(s):

Kacper Szewczyk ◽

Aleksandra Chojnacka ◽

Magdalena Górnicka

Keyword(s):

Vitamin E ◽

Metabolic Disorders ◽

Tissue Concentration ◽

Biological Properties ◽

Biological Role ◽

Future Research ◽

The Past ◽

The Subject ◽

The Relationship

Tocopherols and tocotrienols are natural compounds of plant origin, available in the nature. They are supplied in various amounts in a diet, mainly from vegetable oils, some oilseeds, and nuts. The main forms in the diet are α- and γ-tocopherol, due to the highest content in food products. Nevertheless, α-tocopherol is the main form of vitamin E with the highest tissue concentration. The α- forms of both tocopherols and tocotrienols are considered as the most metabolically active. Currently, research results indicate also a greater antioxidant potential of tocotrienols than tocopherols. Moreover, the biological role of vitamin E metabolites have received increasing interest. The aim of this review is to update the knowledge of tocopherol and tocotrienol bioactivity, with a particular focus on their bioavailability, distribution, and metabolism determinants in humans. Almost one hundred years after the start of research on α-tocopherol, its biological properties are still under investigation. For several decades, researchers’ interest in the biological importance of other forms of vitamin E has also been growing. Some of the functions, for instance the antioxidant functions of α- and γ-tocopherols, have been confirmed in humans, while others, such as the relationship with metabolic disorders, are still under investigation. Some studies, which analyzed the biological role and mechanisms of tocopherols and tocotrienols over the past few years described new and even unexpected cellular and molecular properties that will be the subject of future research.

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