China
Africa
Explore chapters and articles related to this topic
Hydrogels with Ubiquitous Roles in Biomedicine and Tissue Regeneration
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Priyanka, Pooja A Chawla, Aakriti, Viney Chawla, Durgesh Nandini Chauhan, Bharti Sapra
Natural polymers (e.g. collagen and alginate), acellular tissue matrices (e.g. decellularised tissues or organs), and synthetic biodegradable polymers (e.g. polyglycolic acid (PGA), polylactic acid (PLA), poly (lactic-co-glycolic acid) and their copolymers are frequently used for TE application (Kim et al., 2000; Lee et al., 2018). Biomaterials can be classified on the basis of structure as well as function (Dolcimascolo et al., 2019) (Figure10.1 summarises this classification), e.g. whether biomaterials are applied directly in the tissue in the form of injectable (Gutowska et al., 2001) or non-injectable hydrogels; carriers or scaffolds and as surface modification, etc. (Baroli, 2007; Kretlow et al., 2007).
Polymer-Based Protein Delivery Systems for Loco-Regional Administration
Published in Richard L. K. Glover, Daniel Nyanganyura, Rofhiwa Bridget Mulaudzi, Maluta Steven Mufamadi, Green Synthesis in Nanomedicine and Human Health, 2021
Muhammad Haji Mansor, Emmanuel Garcion, Bathabile Ramalapa, Nela Buchtova, Clement Toullec, Marique Aucamp, Jean Le Bideau, François Hindré, Admire Dube, Carmen Alvarez-Lorenzo, Moreno Galleni, Christine Jérôme, Frank Boury
Current research is focused especially on developing biodegradable polymer materials that have shown significant therapeutic potential. Biodegradable polymers are natural or synthetic polymers that are able to degrade in vivo into biocompatible and toxicologically safe by-products that are subsequently resorbed or excreted by the body. Naturally occurring biodegradable polymers are widely explored because of their abundance in nature, biocompatibility and lower toxicity. Chitosan (Deng et al., 2017), hyaluronic acid (Giarra et al., 2018), silk fibroin (Fernández-garcía et al., 2016), cellulose (Wozniak et al., 2003) or collagen (Teixeira et al. 2010; Manavitehrani et al., 2016) have been among the most investigated natural biodegradable polymers for protein delivery applications. However, their use is challenging because of wide molecular weight distributions and batch-to-batch variability and the necessity to collaborate with companies that are able to purchase materials following clinical Good Manufacturing Practices (cGMP). On the other hand, cGMP synthetic biodegradable or bioeliminable polymers are commercially available with different and well-defined compositions, molecular weights and degradation times. Aliphatic polyesters such as poly(lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) have been among the most successfully used synthetic biodegradable polymers so far (Makadia and Seigel, 2011).
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).
PLA–PCL–PEG–PCL–PLA based micelles for improving the ocular permeability of dexamethasone: development, characterization, and in vitro evaluation
Published in Pharmaceutical Development and Technology, 2020
Mitra Alami-Milani, Parvin Zakeri-Milani, Hadi Valizadeh, Marzieh Fathi, Sara Salatin, Roya Salehi, Mitra Jelvehgari
Most of the ocular medications are formulated as eye drops. Due to the anatomical structure of the human eye, only about 30 µl of the eye drops can be administered each time (Jiao 2008). Therefore, drugs with low aqueous solubility should be dissolved at higher concentrations to achieve required therapeutic concentrations in the eye (Alami-Milani et al. 2018), which can cause ocular toxicity. In order to prevent the eye tissue from direct exposure to high concentrations of such drugs, encapsulation of the drug molecules in polymeric nanocarriers can be an ideal approach (Tamboli 2012). Synthetic biodegradable polymers have many advantageous properties, such as biocompatibility, biodegradability, and mechanical strength, making them suitable for biomedical applications. They provide low or negligible toxicity and their degradation products are almost nontoxic considering both local and systemic reactions (Tamboli et al. 2012).
Electrospun nanofibers as versatile platform in antimicrobial delivery: current state and perspectives
Published in Pharmaceutical Development and Technology, 2019
Solmaz Maleki Dizaj, Simin Sharifi, Azin Jahangiri
Research in the field of synthetic biodegradable polymer-based carriers has shown that fibrous scaffolds have been the subject of much investigation in recent years. (Jahangiri and Adibkia 2016; Wunner et al. 2018; Deshmukh et al. 2019). Numerous applications of electrospun fibres have been reported to be the result of their specific features, particularly large surface area-to-volume ratio. Different types of polymers have been successfully electrospun into ultrafine fibres, typically in solvent solution and some in melt form (Huang et al. 2003). Electrospun nanofibrous scaffolds can also be used as carriers for both hydrophilic and hydrophobic compounds, where the compound release profile can be finely controlled by modifying the scaffold’s morphology, porosity and composition (Kim et al. 2004). Processing variables such as (flow rate, voltage and the distance between needle and collector) and solution parameters including conductivity, viscosity, and surface tension of the solution can determine the morphology of final electrospun fibres. The diameters of the prepared fibres using this technology can also vary from tens of nanometers to several micrometres (Payab et al. 2016; Jahangiri et al. 2017).
Enhanced osteogenic activity with boron-doped nanohydroxyapatite-loaded poly(butylene adipate-co-terephthalate) fibrous 3D matrix
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Aysu Arslan, Soner Çakmak, Menemşe Gümüşderelioğlu
Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic co-polyester with high mechanical strength and excellent biodegradability. Moreover, recent studies have shown that it is biocompatible with many cell types. This property makes PBAT a promising synthetic polymeric biomaterial for tissue engineering applications [1–6]. Although synthetic biodegradable polymers have many advantages in terms of mechanical properties such as controlled biodegradation rate and processability into various functional shapes, they are lack of biological signals that limit their cell promotion [7]. Fabrication of polymer-bioactive ceramic composites is a good alternative to produce scaffolds with enhanced bioactivity and mineralization for bone tissue engineering [8].