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What Are Polymeric Carriers?
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
Gülderen Karakuş, Dolunay Şakar Daşdan
Polyacrylic acid (PAA) is a potent adjuvant for primary and secondary immune response. PAA is the general name of synthetic high molecular weight homopolymers of acrylic acid. The solubility of PAA in water increases with a rise in temperature. It is an anionic polymer in a water solution at neutral pH. Many of the side chains have lost their protons and gained a negative charge. With its ability to absorb and retain water due to its hygroscopic nature, it is a polyelectrolyte which can be inflated to a very large extent above the original volume. It is a widely used model polymer for understanding the immunostimulatory properties of synthetic polyelectrolytes. PAA, which is not ionized at low pHs, can be associated with various non-ionic polymers {poly(ethylene oxide), poly(N-vinyl pyrrolidone), polyacrylamide} and some cellulose ethers, and may form hydrogenated interpolymer complexes.
Doxorubicin delivery systems based on doped CaCO3 cores and polyanion drug conjugates
Published in Journal of Microencapsulation, 2021
Natalia Sudareva, Olga Suvorova, Natalia Saprykina, Helen Vlasova, Alexander Vilesov
The release profiles of the drug from CaCO3 cores doped with different PE are frequently close. Therefore, the selection will be determined not by functional characteristics of DS based on CaCO3 cores doped by various PE, but by structural characteristics of these polyelectrolytes. DexSNa and AlgNa are natural polymers, they are utilised in medicine due to biocompatibility and biodegradability (Goh et al.2012, Alavi and Rai, 2019). Although PVSNa and PAANa do not degrade, they can be easily excreted from human body (both polymers have low molecular weights), and are also used in medicine. For example, PVSNa improves the properties of polypropylene suture threads (Volf et al.1982). PAANa is used as a component of materials used in treatment of burns and inflammations to accelerate wound healing. The biological use of PAA derivatives, interpolymer complexes, etc. is described in the paper (Abzaeva et al.1997).
Hydrogels for localized chemotherapy of liver cancer: a possible strategy for improved and safe liver cancer treatment
Published in Drug Delivery, 2022
Jianyong Ma, Bingzhu Wang, Haibin Shao, Songou Zhang, Xiaozhen Chen, Feize Li, Wenqing Liang
From a wide range of monomeric and polymeric constituents, hydrogels are produced such as acrylamide (Zhang et al., 2016) polysaccharides, viz. CTS, starch, cellulose (Abdel-Halim & Al-Deyab, 2014; An et al., 2015; Godiya et al., 2019), ALG (Sahraei & Ghaemy, 2017), gums (Ding et al., 2018), cellulose and rice husk (Gharekhani et al., 2017). Generally, the preparation of hydrogels utilizes either synthetic or natural polymers. When compared to conventional hydrogels, crosslinked junction hydrogels have unique and improved properties such as electrical, thermal, variable MW specific functionality with desired chemical content, and mechanical properties. Alginate-methylcellulose hydrogels that have been blended and cross-linked have shown to be promising materials for encapsulating and delivering olfactory unsheathing cells (OECs). They can be successfully used as a promising system for cell delivery owing to their highest encapsulation potential (Surrao et al., 2020). Electrostatic interactions between two naturally occurring polysaccharides, CTS, and HA resulted in polyelectrolyte multilayers and macroscopic hydrogels. Self-healing properties have been reported in such polyelectrolyte complexes, which can be used in biomedical applications (Barroso et al., 2019). Interpolymer complexes are formed as a result of the association between these poly-ions, which are regulated by specific bonding systems such as electrostatic interaction and hydrogen bonding between distinct polymer chains. Hydrogels are divided into two groups based on the types of cross-link junctions: chemically cross-linked and physically cross-linked.
Polysaccharide nanoparticles for oral controlled drug delivery: the role of drug–polymer and interpolymer interactions
Published in Expert Opinion on Drug Delivery, 2020
Annalisa Bianchera, Ruggero Bettini
Drugs are frequently encapsulated by entrapment in ionic complexes, prepared from one or more polymers: in the first case, nanoparticles are formed by ionic interaction of the polymer with an oppositely charged molecule, while, in the second case, oppositely charged polymers are joined to form interpolymer complexes [30]. In these cases, the structure of nanoparticles is defined by interactions between excipients, and the role and nature of interactions with API must be determined case by case.