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Polysaccharide-Based Hydrogels Drug Delivery in Cancer Therapy
Hydrogels are three-dimensional crosslinked structures with physicochemical properties similar to the extracellular matrix (ECM). By changing the hydrogel’s material type, crosslinking, molecular weight, chemical surface, and functionalization, it is possible to mimic the mechanical properties of native tissues. Hydrogels are currently used in the biomedical and pharmaceutical fields for drug delivery systems, wound dressings, tissue engineering, and contact lenses. Polysaccharide-based hydrogels can be used as drug delivery systems for the efficient release of various types of cancer therapeutics, enhancing the therapeutic efficacy and minimizing potential side effects.
01 Feb 2023
Microplastics Derived from Food Packaging Waste
Plastics are commonly used for packaging in the food industry. The most popular thermoplastic materials that have found such applications are polyethylene (PE), polypropylene (PP), poly(ethylene terephthalate) (PET), and polystyrene (PS). Unfortunately, most plastic packaging is disposable. As a consequence, significant amounts of waste are generated, entering the environment, and undergoing degradation processes. They can occur under the influence of mechanical forces, temperature, light, chemical, and biological factors. These factors can present synergistic or antagonistic effects. As a result of their action, microplastics are formed, which can undergo further fragmentation and decomposition into small-molecule compounds. During the degradation process, various additives used at the plastics’ processing stage can also be released. Both microplastics and additives can negatively affect human and animal health.
29 Jan 2023
Sustainable Polymeric Food Packaging Films
Food packaging is fundamental to ensuring food distribution and protection around the world, especially when considering the solid growth of the population. Without packaging, food would easily spoil and the distribution of enormous quantities of food, raw and processed, to different areas around the globe would hardly be possible.
16 Jan 2023
Electrospun Polymer Nanofibers
Electrospun polymer nanofibers constitute one of the most important nanomaterials with diverse applications. Nanofibers are classified as fibers with a ratio of length to thickness in the order of one thousand, or nanomaterials that have at least one dimension of 100 nm or less. A nanofiber with a diameter of ∼100 nm can have a specific surface area up to 1000 m2/g. Nanofibers can be produced by selecting the proper combination of polymers and additives, and using appropriate production techniques based on several essential characteristics that impact criteria of the intended particular application area. Electrospinning of polymer nanofibers is a widely used for investigation of their properties for uses in quite diverse applications. Attractive properties of electrospun nanofibers include the extremely high specific surface area, high porosity (typically 90%), light weight, controllable pore size, flexibility in surface functionalities, large permeability, excellent mechanical properties, high aspect ratio, and length up to many centimeters. Due to their exceptional characteristics, electrospun polymer nanofibers are used in many applications, which include biomedical technology, such as tissue engineering, wound healing and dressing, and drug delivery systems. In addition they have diverse uses in sensors and biosensors applications, air filtration, defense applications, energy devices and protective textiles.
12 Jan 2023
Design and Synthesis of Polyphosphodiesters
Polyacids containing –P(O)(OH)– fragment in the polymer backbone, or polyphosphodiesters (PPDEs), hold a special place among natural and synthetic polymers. The structural similarity of PPDEs to natural nucleic and teichoic acids, biocompatibility of PPDEs and their mimicking to biomolecules providing the ‘stealth effect’, high bone mineral affinity of PPDEs, and adjustable hydrolytic stability of PPDEs are the basis for various biomedical, industrial and household applications. Actual synthetic approaches to PPDEs are based on incredibly rich chemistry of organic phosphates and phosphonates, and include modern techniques such as catalytic ring-opening polymerization (ROP), acyclic diene metathesis (ADMET) polycondensation, and others.
09 Jan 2023
Fluoropolymer Membranes for Membrane Distillation and Membrane Crystallization
Fluoropolymer membranes are applied in membrane operations such as membrane distillation and membrane crystallization where hydrophobic porous membranes act as a physical barrier separating two phases. Due to their hydrophobic nature, only gaseous molecules are allowed to pass through the membrane and are collected on the permeate side, while the aqueous solution cannot penetrate. However, these two processes suffer problems such as membrane wetting, fouling or scaling. Membrane wetting is a common and undesired phenomenon, which is caused by the loss of hydrophobicity of the porous membrane employed. This greatly affects the mass transfer efficiency and separation efficiency. Simultaneously, membrane fouling occurs, along with membrane wetting and scaling, which greatly reduces the lifespan of the membranes. Therefore, strategies to improve the hydrophobicity of membranes have been widely investigated by researchers. In this direction, hydrophobic fluoropolymer membrane materials are employed more and more for membrane distillation and membrane crystallization thanks to their high chemical and thermal resistance.
03 Jan 2023
Polystyrene vs. Polylactide
Polystyrene (PS) is a thermoplastic polymer made of aromatic hydrocarbon monomer styrene that is derived from fossil-fuels. The synthesis of PS is based on the free radical polymerization of styrene using free-radical initiators. It is mostly used in solid (high impact and general purpose PS), foam and expanded PS forms. The main advantages of PS are low-cost, easy processing ability, and resistance to ethylene oxide, as well as radiation sterilization. Polylactide (PLA)—biodegradable and compostable aliphatic polyester—is one of the key biopolymers with the largest market significance.
28 Dec 2022
Enzyme-Catalyzed Synthesis of Polyesters
Polyester is a kind of polymer composed of ester bond-linked polybasic acids and polyol. This type of polymer has a wide range of applications in various industries, such as automotive, furniture, coatings, packaging, and biomedical. The traditional process of synthesizing polyester mainly uses metal catalyst polymerization under high-temperature. This condition may have problems with metal residue and undesired side reactions. As an alternative, enzyme-catalyzed polymerization is evolving rapidly due to the metal-free residue, satisfactory biocompatibility, and mild reaction conditions.
20 Dec 2022
Versatile Polyaniline-Based Polymers in Food Industry
Intrinsically conducting polymers (ICPs) have been widely studied in various applications, such as sensors, tissue engineering, drug delivery, and semiconductors. Specifically, polyaniline (PANI) stands out in food industry applications due to its advantageous reversible redox properties, electrical conductivity, and simple modification. The rising concerns about food safety and security have encouraged the development of PANI as an antioxidant, antimicrobial agent, food freshness indicator, and electronic nose. At the same time, it plays an important role in food safety control to ensure the quality of food.
14 Dec 2022
Recycling of High-Molecular-Weight Organosilicon Compounds in Supercritical Fluids
The main known patterns of thermal and/or catalytic destruction of high-molecular-weight organosilicon compounds are considered from the viewpoint of the prospects for processing their wastes. The advantages of using supercritical fluids in plastic recycling are outlined in this entry. They are related to a high diffusion rate, efficient extraction of degradation products, the dependence of solvent properties on pressure and temperature, etc. A promising area for further research is described concerning the application of supercritical fluids for processing the wastes of organosilicon macromolecular compounds.
14 Dec 2022
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