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Nanoparticles from Marine Biomaterials for Cancer Treatment
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Curing turns the polymers into a solidified mass by establishing three- dimensional linkages inside the polymer mass using thermal, electrochemical, or ultraviolet (UV) radiation treatment processes, whereas graft copolymerization includes covalent bonding of polymers (J. Li et al. 2018). Some hydrophilic polymers can be blended with poly (vinyl alcohol) (PVA), poly (vinyl pyrrolidone) (PVP) and poly (ethyl oxide) (PEO) for drug delivery. CHT-PVA blends improve its mechanical and barrier qualities. The intermolecular interactions between CHT and PVA produce PVA-CHT blends with better mechanical properties (tensile strength) for regulated drug administration. After blending, the characterization of CHT blends can be done via Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD; Mohammed et al. 2017).
Bio-Implants Derived from Biocompatible and Biodegradable Biopolymeric Materials
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
PBS is biodegradable aliphatic polyesters which is one of the members of biodegradable polymers family. In order to improve the properties number of copolymerization stages are made according to Darwin et al. [37]; Jin et al. (2000, 2001). Phenyl units are introduced into the side chain of PBS, which leads to the better biodegradability of the copolyesters. Jung et al. (1999) successfully synthesized new PBS copolyesters containing alicyclic 1; 4-cyclohexanedimethanol. The applications for PLA are mainly as thermoformed products such as drink cups, take-away food trays, containers, and planter boxes. Polystyrene and PET are partially replaced with PLA material due to the rigidity. Applications include mulch film, packaging film, bags, and ‘flushable’ hygiene products [38].
Pharmaceutical and Methodological Aspects of Microparticles
Published in Neville Willmott, John Daly, Microspheres and Regional Cancer Therapy, 2020
Yan Chen, Mark A. Burton, Bruce N. Gray
For biodegradable microparticles prepared from polyesters, degradation can be affected by the hydrophobicity and the crystallinity of the polymer98,110 and the presence of plasma proteins.111 Thus, a high degree of hydrophobicity or crystallinity can slow the process of hydration and water penetration, resulting in slow degradation. Copolymerization destroys a polymer’s crystallinity, which may produce more readily degradable matrices.110 In a systematic study of the relationship between proportion of polylactate/polyglycolate and degradation rate, it was found that the copolymer of lactic acid and glycolic acid (1:1) showed the maximal biodegradation rate in vivo.112 With regard to the presence of plasma proteins, their adsorption on the surface of poly(l-lactide) microcapsules causes an increase in H+ concentration at the surface as well as increases the solubility of the polymer. In turn, these accelerate the degradation of poly(l-lactide) microcapsules.111
Development and biocompatibility of the injectable collagen/nano-hydroxyapatite scaffolds as in situ forming hydrogel for the hard tissue engineering application
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2021
Armin Hassanzadeh, Javad Ashrafihelan, Roya Salehi, Reza Rahbarghazi, Masomeh Firouzamandi, Mahdi Ahmadi, Majid Khaksar, Mahdieh Alipour, Marziyeh Aghazadeh
As 3D scaffolds, the hydrogels consisting of natural and synthetic polymers have many advantages similar to in vivo ECM [5]. Collagen is one of the most common natural polymers in regenerative medicine due to its excellent biological features [8]. However, natural hydrogels are mechanically weak due to a high amount of water absorption. To overcome this limitation, the synthesized polymers and nanoparticles are usually added to the natural polymers to improve the physicochemical properties of the hydrogels [9,10]. Among the synthetic polymers used in tissue engineering, poly (ɛ-caprolactone) (PCL) is biodegradable and biocompatible polyester with superior mechanical strength [11]. However, this polymer is insoluble and has a low degradation rate [12]. Therefore, efforts have been made to circumvent these pitfalls by copolymerization with the polyethylene glycol [13]. Moreover, it has been shown that the nHA particles have the potential to enhance the osteogenesis capacity of the scaffolds. Degradation of these particles releases the calcium and phosphate ions, which could dictate certain mineralization signalling pathways [14–16].
Microbial polyhydroxyalkanoates as medical implant biomaterials
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Block copolymerization can add new properties to PHA. For example, poly(ether-ester urethane)s (PUs) multiblock copolymers synthesized from telechelic hydroxylated PHBHHx and PEG via a melting polymerization (MP) process using 1,6-hexamethylene diisocyanate (HDI) as a non-toxic coupling agent showed better mechanical and biological properties. The PHBHHx segments and PEG segments in the multiblock copolymers behaved as a hard, hydrophobic and a soft, hydrophilic part, respectively. Implantation of the multiblock copolymers in mouse abdominal cavity indicated that tissue regeneration and tissue compatibility of the film were better than that of PHBHHx-only film [82–84]. Similar results were observed for PHB-PEG and PHB-PMLA films [85–87]. Similarly, better results were also observed for RaSMCs and immortalized human keratinocyte (HaCaT) cells grown on P3HB4HB- and PHBHHx-based polyurethane as a hydrophobic wound healing and haemostatic materials compared with PLA, PHB, P3HB4HB and PHBHHx [88].
A novel multi-stimuli-responsive theranostic nanomedicine based on Fe3O4@Au nanoparticles against cancer
Published in Drug Development and Industrial Pharmacy, 2020
Bakhshali Massoumi, Amir Farnudiyan‐Habibi, Hossein Derakhshankhah, Hadi Samadian, Rana Jahanban-Esfahlan, Mehdi Jaymand
The FTIR spectra of the (S-PNIPAAm)2 and (S-PNIPAAm-b-PAA)2 are shown in Figure 2. The FTIR spectrum of the (S-PNIPAAm)2 exhibited the characteristic absorption bands due to the stretching vibration of –NH secondary amid at 3600–3200 cm−1, the carbonyl stretching vibration of amide group at 1648 cm−1, the stretching vibration of aliphatic –CH at 2950–2750 cm−1 region, and the bending vibrations of –CH at 1458 and 1369 cm−1. The most important changes after block copolymerization of acrylic acid monomer are the appearance of the stretching vibration of carbonyl group (related to carboxylic acid) at 1736 cm−1 and the stretching vibration of C–O group at 1125 cm−1.