Reactive Secondary Sequence Oxidative Pathology Polymer Model and Antioxidant Tests

Abstract

Aims-To provide common Organic Chemistry/Polymer Science thermoset free-radical crosslinking Sciences for Medical understanding and also present research findings for several common vitamins/antioxidants with a new class of drugs known as free-radical inhibitors.Study Design-Peroxide/Fenton transition-metal redox couples that generate free radicals were combined with unsaturated lipid oils to demonstrate thermoset-polymer chain growth by crosslinking with the α-β-unsaturated aldehyde acrolein into rubbery/adhesive solids. Further, Vitamin A and beta carotene were similarly studied for crosslink pathological potential. Also, free-radical inhibitor hydroquinone was compared for antioxidant capability with Vitamin E.Methodology-Observations were recorded for Fenton free-radical crosslinking of unsaturated lipids and vitamin A/beta carotene by photography further with weight measurements and percentshrinkage testing directly related to covalent crosslinking of unsaturated lipids recorded over time with different concentrations of acrolein. Also, hydroquinone and vitamin E were compared at concentrations from 0.0-7.3wt% as antioxidants for reductions in percent-shrinkage measurements, n = 5.Results-Unsaturated lipid oils responded to Fenton thermoset-polymer reactive secondary sequence reactions only by acrolein with crosslinking into rubbery-type solids and different nonsolid gluey products. Further, molecular oxygen crosslinking was demonstrated with lipid peroxidation and acrolein at specially identified margins. By peroxide/Fenton free-radical testing, both vitamin A and beta-carotene demonstrated possible pathology chemistry for chain-growth crosslinking. During lipid/acrolein testing over a 50 hour time period at 7.3wt% antioxidants, hydroquinone significantly reduced percent shrinkage greatly compared to the standard antioxidant vitamin E, %shrinkage at 11.6 ±1.3 for hydroquinone and 27.8 ±2.2 for vitamin E, P = .001.Conclusion-Free radicals crosslinked unsaturated lipid fatty acids into thermoset polymers through Fenton reactions when combined with acrolein. Further, hydroquinone was a superior antioxidant to vitamin E.

Computational conformational antimicrobial analysis developing mechanomolecular theory for polymer biomaterials in materials science and engineering

“…In fact, triclosan has been considered to induce metabolic stress on bacterial cells that indicates related enzyme expression is compromised [Greenman et al ., 1997]. In addition, free-radicals should further be considered biologically for lipid crosslinking as a form of polymerization cure shrinkage with covalent bond formation in unsaturated lipid fatty acids with carbon–carbon double bonds [Petersen, 2012] that could secure triclosan closer in to the membrane lipid chains for rotation bond entanglements, hydrogen bonding, van der Waals attractions, pi–pi aromatic stacking alignments and cell death. Further, from results on high triclosan concentrations in the resin, in a nonpolar lipid membrane environment triclosan ether bond rotation should be minimized to not delocalize electron radicals into a ring and inhibit unsaturated fatty acid crosslinking.…”

“…16, is presented with a relatively larger BisGMA molecule without sp 3 hybridized bond angels. The model loosely shows how initial covalent crosslinks can start at each end of the BisGMA unit and continue free-radical reactive secondary sequence polymerization from the carbon atoms on the other sides of the double bonds into large macromolecules of considerable size [Annusavice, 2003; Sperling, 2006; Petersen, 2012]. More importantly for understanding blending of chemical additive combinations with polymers, analogous molecular similarities between triclosan with two aromatic rings and center oxygen ether bonds match well with the BisGMA molecular polymer unit at midpoint center for compatibilization through similar molecular polarities or electron distributions with two phenyl aromatic rings and associated lateral oxygen ether groups.…”

Free-Radical Polymer Science Structural Cancer Model: A Review

“…Other reactive free-radical species can also be formed as well [19]. By definition, a free radical is a molecule that contains an unpaired electron which is highly unstable and seeks out another electron for a stable covalent bond pair [15, 22–24]. Subsequent hypoxic free-radical species are then involved in damage to lipids, proteins, and DNA [15, 18, 19, 24].…”

“…In terms of similarities with a basic chemistry understanding for molecular pathobiology, polymer science unsaturated alkene chain-growth free-radical covalent bond formation with increased liquid/resin viscosity by molecular crosslinking toward solid structure produces irregular shrinkage patterns [22]. Further, from polymer science free radicals polymerize unsaturated resins to produce increased material modulus (or stiffness) with higher density measured as reduced bulk volume percent from shorter interatomic bond distances [22, 25–27].…”

“…Further, from polymer science free radicals polymerize unsaturated resins to produce increased material modulus (or stiffness) with higher density measured as reduced bulk volume percent from shorter interatomic bond distances [22, 25–27]. In fact, the most characteristic subsequent manifestations of overall polymerization crosslinking is material shrinkage with some internal stresses and warpage [22, 25–27]. A highly common free-radical cure method in past has been a resin system with styrene monomer and dibenzoyl peroxide, depicted in Figure 3, to illustrate free-radical reactive secondary sequence by crosslinking across a carbon-carbon (C=C) vinyl double bond [22].…”