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What Are Polymeric Carriers?
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
Gülderen Karakuş, Dolunay Şakar Daşdan
Mass or bulk polymerization of monomers such as initiators and chain transfer agents in the form of dissolved or poorly soluble monomer phase based on the polymerization of the medium. The medium involves a monomer and an initiator as the main components, without a solvent. The polymer formed is soluble in the styrene, such as poly(methyl methacrylate) (PMMA), methyl methacrylate, in the styrene. Viscous liquid is formed when the monomer is polymerized at a rate of 10–20%. If the reaction is carried out further, it may be difficult to remove the polymer from the reaction media. The monomers which undergo condensation polymerization are usually polymerized by this method. Foreign substances are less likely to enter the polymerization medium and the polymeric product is very easy to separate (Adumitrăchioaie 2018; Nesvadba 2012).
Injectable Scaffolds for Bone Tissue Repair and Augmentation
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Subrata Bandhu Ghosh, Kapender Phogat, Sanchita Bandyopadhyay-Ghosh
Reinforcing bone by injecting a cementitious bone substitute such as poly (methyl methacrylate) (PMMA) is a common technique and is found to be effective for vertebral fractures. However, during the setting process, PMMA based cement has been reported to generate monomer toxicity and excessive heat that may lead to bone necrosis (Schoenfeld et al. 1979, Karlsson et al. 1995, Galibert et al. 1987, Deramond et al. 1997, Bohner et al. 2006). An alternative to PMMA is calcium phosphate cements (CPC) which are made of calcium phosphate particles dispersed in an aqueous solution. They are usually considered to be injectable, although their injectability is often found to be poor. Self-setting of calcium phosphate cements can happen in vivo assisted by the aqueous medium present at the biological target site (Hou et al. 2004, Bohner et al. 2006).
Nanocarrier Technologies for Enhancing the Solubility and Dissolution Rate of Api
Published in Debarshi Kar Mahapatra, Sanjay Kumar Bharti, Medicinal Chemistry with Pharmaceutical Product Development, 2019
Ashwini Deshpande, Tulshidas S. Patil
Synthetic polymers such as polystyrene, poly (cyanoacrylates) like poly(isobutylcyanoacrylate) (PICBA), poly (isohexyl cyanoacrylates) (PIHCA), poly(n-butylcyanoacrylate) (PBCA), poly(acrylate) and poly(methacrylate) (Eudragit), poly (methyl methacrylate) (PMMA), and polyethyleneimine can be used for oral drug delivery.
Influence of sequential opening/closing of interface gaps and texture density on bone growth over macro-textured implant surfaces using FE based mechanoregulatory algorithm
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Rajdeep Ghosh, Souptick Chanda, Debabrata Chakraborty
Intramedullary implant fixation is a standard surgical procedure which is extensively used in re-establishing fractured bones and joints, further aiding to the treatment of various joint diseases such as osteoarthritis (OA), rheumatoid arthritis (RA), femoral fractures etc. Contributing to the sedentary lifestyle among youth, increase in road accidents and ageing population in developed nations, there is a tremendous increase in need for joint replacements globally (Holzwarth and Cotogno 2012; Cilla et al. 2017; Sánchez, Schilling, Grupp, Giurea, Wyers, et al. 2021). There are primarily two types of intramedullary implantation widely used presently. Cemented fixation, in which bone cement, commercially known as poly (methyl methacrylate) or PMMA, is used to adhere the implant to the host bone by drilling a canal of required diameter into the healthy bone. On the other hand, in uncemented fixation, the implant is forced (press-fit or interference-fit) into the healthy bone canal without the use of bone cement. Primary fixation of such implants is achieved by the interference-fit and frictional conditions of the surface, which further aids to the enhancement of biologic fixation of bone to the implant, also referred to as secondary stability (Ghosh et al. 2020; Sánchez, Schilling, Grupp, Giurea, Wyers, et al. 2021). A proper combination of both primary stability and secondary fixation is crucial for long-term success of such intramedullary fixation devices (Ghosh et al. 2020).
Release behavior, mechanical properties, and antibacterial activity of ciprofloxacin-loaded acrylic bone cement: a mechanistic study
Published in Drug Development and Industrial Pharmacy, 2020
Marzieh Gandomkarzadeh, Arash Mahboubi, Hamid Reza Moghimi
Nowadays the use of ultraclean air theaters, perioperative antibiotics and antibiotic-loaded bone cement (ALBC) leads to a significant reduction in risk of infections [4]. Addition of antibiotics in poly(methyl methacrylate) (PMMA) bone cements is appropriate to treat and prevent orthopedics infections, for decades. In fact, acrylic bone cement, in addition to its role as a biomaterial used in total hip and knee arthroplasty surgeries, could act as a drug carrier to decrease the rate of infections at the site of action. The United States Food and Drug Administration (FDA) has approved ALBC products for second-stage of two-stage total joint replacement surgery due to infection. This drug delivery system is an alternative for systemic drug delivery systems with low efficacy in bone infections. The antibiotic impregnated bone cement provides higher concentration of drug at the infection site and effectively inhibits infections with much less side effects in comparison to systemic administration [5–7]. Novel antimicrobial agents like silver and gold nanoparticles have also been developed for the improvement of bone cement antibacterial features against resistant strains [8–10]. PMMA bone cement, are also designed as beads or spacers for treatment of musculoskeletal infections in the revision surgery [11].
Temporal augmentation with poly methyl methacrylate at the time of autologous cranioplasty
Published in British Journal of Neurosurgery, 2020
Justin R. Davanzo, Scott D. Simon
Poly methyl methacrylate addresses each of the issues outlined above. While the substance begins as a cement-like substance, it quickly hardens, reducing the risk of intracranial extravasation at the time of surgery. Also, poly methyl methacrylate is a readily available substance in most hospitals. Thus, this does not require specific pre-surgical planning. In addition, poly methyl methacrylate is inexpensive. In our hospital, 40cc costs $50. Compared to other products such as hydroxyapatite granules ($2,973 for 10cc or $4,275 for 15cc) or the synthetic temporal implants (approximately $795), this product is significantly less expensive. Even when using the small mesh plate to reinforce the temporal region ($162 at our facility), the overall cost of our construct remains significantly less than other comparable and available products. Finally, this substance, until it hardens, is very moldable. This allows us to provide a custom fit for each patient’s particular case.