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Biodegradable Polymers as Drug Carrier Systems
Published in Severian Dumitriu, Valentin Popa, Polymeric Biomaterials, 2020
Polyanhydrides are a novel class of biodegradable polymers under development as vehicles for the release of bioactive molecules including drug peptides and proteins. A series of biocompatibility studies reported on several polyanhydrides have shown them to be nonmutagenic and nontoxic (Leong et al. 1986). In vitro tests measuring teratogenic potential were also negative. Growth of two types of mammalian cells in tissue culture was also not affected by the polyanhydride polymers (Leong et al. 1986); both the cellular doubling time and cellular morphology were unchanged when either bovine aorta endothelial cells or smooth muscle cells were grown directly on the polymeric substrate.
Designing Biomaterials for Regenerative Medicine: State-of-the-Art and Future Perspectives
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Zohreh Arabpour, Mansour Youseffi, Chin Fhong Soon, Naznin Sultana, Mohammad Reza Bazgeir, Mozafari Masoud, Farshid Sefat
The synthetic biodegradable polymers are major groups of polymers that are popular in tissue engineering. These biodegradable and noncytotoxic materials can support cell attachment, proliferation and differentiation to reconstruct tissue defect (Guelcher 2008). A major difference between natural biopolymers and synthetic polymers is in their structures. Most synthetic polymers have much simpler than natural polymer structures. The degradation rate of these groups of materials are adjustable by changing the mixing ratio, molecular weight of components and other parameters to match with the regeneration rate of the tissue. Polyanhydrides, polyesters, polyphosphazenes, poly (glycerol sebacate) and polyurethanes are classified in this group of materials. This group can be manipulated to the desirable characteristics. Since polyanhydrides possess high hydrophobicity and favorable degradation pattern (degradation from the surface to the inside), they are appropriate for drug-delivery applications (Jain et al. 2008).
Bionanocomposites, Their Processing, and Environmental Applications
Published in Shakeel Ahmed, Saiqa Ikram, Suvardhan Kanchi, Krishna Bisetty, Biocomposites, 2018
Sagar Roy, Chaudhery Mustansar Hussain
Polyanhydrides are synthesized using anhydrides, diacids, or diacid esters with diacyl chlorides via several polymerization techniques, including melt condensation, ring opening, interfacial condensation, etc. Owing to two hydrolyzable sites in the main polymer backbone chain, polyanhydrides have become one of the most significant biodegradable materials. The presence of aromatic groups in the backbone resists the biodegradation rate compared to aliphatic polyanhydrides. Aliphatic homopolymers, such as poly(sebacic anhydride), exhibit high crystallinity, which hinders its practical applications. The fast biodegradation rate may be controlled by the use of hydrophobic groups in the diacid building block. Biomaterials produced from carboxyphenoxypropane have been thoroughly studied. The products formed after biodegradation are non-toxic and biocompatible. Copolymerization with other monomers improved the desired properties of polyanhydrides. Combination with imide enhances mechanical properties suitable for specific medical applications.
Regenerated silk fibroin loaded with natural additives: a sustainable approach towards health care
Published in Journal of Biomaterials Science, Polymer Edition, 2023
Niranjana Jaya Prakash, Xungai Wang, Balasubramanian Kandasubramanian
The use of biodegradable materials in biomedical devices provides a greener and more sustainable approach toward next-generation biomedical engineering [6–8]. Various biodegradable polymeric systems such as polyesters [9], polphosphazenes [10], polysaccharides, and polyanhydrides have been developed to date for the fabrication of biomedical devices such as stents, scaffolds, fixation devices, and cathedrals with product names Vicryl® (Ethicon), Dexon® (American Cyanamide Co.), and Polyzene-F® (poly[bis(trifluoroethoxy) phosphazene], CeloNova BioSciences). However the in-vivo degradation of these systems can cause adverse effects based on the degradation mechanism followed under certain environmental conditions [11]. The leaching of monomeric units such as triethylene glycol dimethacrylate and bisphenol-A-glycidyl methacrylate can result in the alteration of cellular metabolism. Even FDA-approved products such as polylactic acid (PLA) and polyglycolic acid (PGA) can undergo in-vivo acidic degradation causing mild inflammatory reactions which necessitate the compound to be biostable along with being biodegradable. However, the major impediment in the pathway of developing completely natural biomedical devices is the lack of mechanical integrity and ease of processing. Hence the development of natural composites possessing significant mechanical strength along with their inherent characteristics, such as biodegradability and biocompatibility, presents a considerable revolution.
Amphiphilic block copolymer NPs obtained by coupling ricinoleic acid/sebacic acids and mPEG: Synthesis, characterization, and controlled release of paclitaxel
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Shiya Zhou, Wei Sun, Yinglei Zhai
Materials approved by US Food and Drug Administration (FDA) play an important role in the field of polymeric formulations [15]. Polyanhydrides (PAs) as an approved synthetic biopolymers have been widely investigated for controlled drug release owing to their demonstrated biodegradability and biocompatibility [16,17]. Surface erosion is one of the fundamental properties for the controlled drug release system. Even though anhydride bond is more labile than other bonds such as ester, amide, carbonate, etc., rational fabrication of copolymers can render the formulation consisting of PAs more stable through the hydrophobic interaction and realize surface erosion [18]. This will benefit the improvement for the pharmacokinetics of hydrophobic drugs [19]. Micro or nano-formulations based on PAs have been developed via various fabrication methods in extended medical fields [20–24]. However, PAs polymerized by single monomer seems to be insufficient for the flexible drug release, copolymers strategy like poly(anhydride-esters) (PAEs) is more preferred.