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Three-Dimensional Printing: Future of Pharmaceutical Industry
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Manju Bala, Anju Dhiman, Harish Dureja, Munish Garg, Pooja A Chawla, Viney Chawla
Sandler et al utilise nitrofurantoin (poorly soluble drug) having activity against microbes and urinary tract infections. Poly lactic acid was used as a biodegradable polymer. This further resulted in inhibition of biofilm colonisation (Sandler et al. 2014).
Vaccine Adjuvants in Immunotoxicology
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
Nanoparticles are manufactured using albumin, collagen, starch, chitosan, and dextran out of natural polymers and polymethylmethacrylate, polyesters, polyanhydrides, and polyamides among synthetic polymers (Li et al. 2014). There are biodegradable or non-biodegradable polymers. Non-biodegradable polymers may cause unexpected effects by accumulation in the body. In the vaccine studies, the characteristics such as toxic effects of the polymer on the organism, antigen release speed capacity, stability status under storage conditions, and stability in the in vivo conditions should be taken into account in making a decision for an ideal polymer carrier system (Skwarczynski and Toth 2011, 2016). The comprehensive toxicity tests for several synthetic polymers such as polyesters, polylactic acid (PLA), polyglycolic acid, and their copolymers poly(lactic-co-glycolic acid) (PLGA) have been carried out and they are FDA-approved for use in humans (Li et al. 2014; Cordeiro and Alonso 2016). The most commonly used biodegradable polymers are PLA, PLGA, polyglutamic acid (PGA), polycaprolactone (PCL), and polyhydroxybutyrate. PLGA is the most frequently used polymer in the nanoparticle studies (Li et al. 2014). Skwarczynski and Toth (2011) have reported in their study that MUC-1 peptide vaccine assembled into PLGA nanoparticle carrier system accompanied with adjuvant MPLA created immune response by inducing T cells. However, it has been noted in the same article that need for use of adjuvant in the PLGA-based systems still continues (Skwarczynski and Toth 2011).
Polymer Materials for Oral and Craniofacial Tissue Engineering
Published in Vincenzo Guarino, Marco Antonio Alvarez-Pérez, Current Advances in Oral and Craniofacial Tissue Engineering, 2020
Iriczalli Cruz Maya, Vincenzo Guarino
PGA is characterized by low solubility in most organic solvents, as a function of the molecular weight. However, as molecular weight is too low, the solubility increases but the mechanical properties can be lost (Ma and Langer 1995). PGA was first used for absorbable sutures, due to its relative hydrophilicity nature which allows its rapid degradation and loss of its mechanical integrity in around 2-3 weeks (Ma and Langer 1995). PLA and PGA are biocompatible materials, with controllable degradation rate depending on chemical structure, molecular weight and crystallinity of polymers (Pamula et al. 2001). In order to extend the applicative use of PGA, it has been used to form co-polymer with PLA, a more hydrophobic polymer, suitable to regulate the degradation of PGA. Poly(lactic acid-co-glycolic acid) (PLGA) may combine the advantages of both polymers, by modulating the co-polymer composition. For instance, high fractions of glycolic acid make the PLGA degradation faster, higher portions of PLA make it stiffer (Makadia and Siegel 2011). PLGA has been used for tissue engineering scaffolds and particularly to fabricate nanoparticles for drug delivery systems, due to the broad range of the degradation time (Moioli et al. 2007; Makadia and Siegel 2011; Danhier et al. 2012).
Synthetic biodegradable polyesters for implantable controlled-release devices
Published in Expert Opinion on Drug Delivery, 2022
Jinal U. Pothupitiya, Christy Zheng, W. Mark Saltzman
Polylactide (PLA) or polylactic acid is a biodegradable polyester, which is extensively used in the textile, packaging, and biomedical industries. Polylactide is synthesized from lactide monomers and polylactic acid from lactic acid. The widespread use of PLA is attributed to its relatively simple bulk production methods, high abundance, recyclability, composability, and mechanical strength (which is comparable to polystyrene). Furthermore, the long history of PLA use in implanted devices – and its well-characterized biodegradability – make it an attractive material for biomedical implants. PLA is synthesized from lactic acid or lactide, which are monomers derived from renewable resources such as corn, wheat, carbon dioxide, and rice. The polymer degrades in biological systems by hydrolysis and enzymatic activity to produce lactic acid, which is a natural metabolite in the body. PLA is generally recognized as safe; it is a component in many FDA-approved products [2,111,112].
Injectable and adhesive hydrogels for dealing with wounds
Published in Expert Opinion on Biological Therapy, 2022
Parisa Ghandforoushan, Nasim Golafshan, Firoz Babu Kadumudi, Miguel Castilho, Alireza Dolatshahi-Pirouz, Gorka Orive
Designing injectable, efficient, and cost-effective tissue adhesive biomaterials is an unmet clinical demand for the minimally invasive sealing of injured tissues, especially while sutures or staples are not desirable [47]. Injectable biomaterials have been assessed for application in tissue engineering domain for their impressive features, such as the comfort of handling, rendering better integration of the native tissue through filling irregular defects, and holding controllable chemical and physical attributes, thereby accelerating the repair process [48,49]. These distinct features of injectable biomaterials can overwhelm the limitations of cell adhesion, cell seeding, and delivery of therapeutic factors as they can be merged with the material solution before in situ injections [50]. Injectable biomaterials expedite a minimally invasive procedure compared to traditional open operations, which can decrease the expense, and speed up the recovery time for the sufferers [51]. For hard tissues, such as bone and dental, calcium phosphate cement (CPCs) has been admitted as a promising injectable material due to their capacity to harden in situ also their chemical similarity to the bone. Nevertheless, CPC injectable materials suffer some drawbacks like brittleness [52]. Poly (lactic acid)-based biomaterials and collagen are proper injectable biomaterials candidates for dental tissue engineering [53]. The main drawbacks lying with injectable materials are their manipulation and handling to be placed into the target sites.
Polymeric nanodroplets: an emerging trend in gaseous delivery system
Published in Journal of Drug Targeting, 2019
Poly(lactic acid) (PLA) is a non-toxic, biodegradable polymer that is widely used for the formation of nanoparticles [37]. A recent study employed PLA (Mw ∼120,000) for the formation of quercetin-based nanoparticle for the treatment of breast cancer. In this study, nanoparticles were formulated with different concentration of PLA (10, 20, 30 and 40 mg/ml) and it was found that higher concentration of polymer leads to increase in particle size in presence of drug. The particle size of the nanoparticles ranged from 32 ± 8 to 153 ± 9 nm with entrapment efficiency between 51 ± 2 and 65 ± 3%. Hence, the optimum concentration of PLA was found to be 20 mg/ml that resulted in smaller particle size and higher entrapment efficiency (62 ± 3%) in comparison to 30 and 40 mg/ml with 65% entrapment efficiency. Thus, it was concluded that quercetin nanoparticles with 20 mg/ml concentration of PLA has highest entrapment efficiency and suitable for treatment [38]. Owing to the properties of PLA, it functions as a model polymer for the formation of uniform-sized NDs. A recent study involves two methods for formation of NDs by emulsion solvent and premix membrane emulsification method. The combination of these two methods resulted in the formation of uniform-sized PLA NDs [39].