Soluble synthetic polymer effects

Water soluble polymers are well represented in the human environn nt and in food. Thus, our very existence constitutes solid proof of the lack of the physiological effects of many of these compounds. Nevertheless, some water soluble synthetic polymers, even at very low concentrations, influence enzymatic processes that form the basis of the physiology of the body. The reason for a general lack of bioactivity of synthetic polymers on the organism s level is the inability of polymers to penetrate to the location where the body s basic biochemical processes occur. The human body s most prevailing component is water (>fi)%). However, this body of water is not a continuous phase, it is subdivided by lipid membranes into spaces of microscopic size. Lipids constitute about 15% of body weight and a considerable portion of that amount is used to form and maintain cellular membranes, a structural element of the body that diminishes the mobility of hydrophilic polymers in organisms. 

THE EFFECT OF SOLUBLE SYNTHETIC POLYMERS ON PROTEIN SOLUBILITY... 

Duncan R. Biological effects of soluble synthetic polymers as drug carriers. CRC Critical Rev Therap Drug Carrier Sys 1985 1(4) 281-310. 

TSK-GEL PW type columns are commonly used for the separation of synthetic water-soluble polymers because they exhibit a much larger separation range, better linearity of calibration curves, and much lower adsorption effects than TSK-GEL SW columns (10). While TSK-GEL SW columns are suitable for separating monodisperse biopolymers, such as proteins, TSK-GEL PW columns are recommended for separating polydisperse compounds, such as polysaccharides and synthetic polymers. 

Many synthetic water-soluble polymers are easily analyzed by GPC. These include polyacrylamide,130 sodium poly(styrenesulfonate),131 and poly (2-vinyl pyridine).132 An important issue in aqueous GPC of synthetic polymers is the effect of solvent conditions on hydrodynamic volume and therefore retention. Ion inclusion and ion exclusion effects may also be important. In one interesting case, samples of polyacrylamide in which the amide side chain was partially hydrolyzed to generate a random copolymer of acrylic acid and acrylamide exhibited pH-dependent GPC fractionation.130 At a pH so low that the side chain would be expected to be protonated, hydrolyzed samples eluted later than untreated samples, perhaps suggesting intramolecular hydrogen bonding. At neutral pH, the hydrolyzed samples eluted earlier than untreated samples, an effect that was ascribed to enlargement... 

Other investigators have also studied similar synthetic polymers.11-17 In our experience no water-soluble polymer binds small molecules with an avidity comparable to serum albumin. A comparison of the latter with two of the best-binding polymers18 is shown in Fig. 1. Neither polymer binds as strongly as serum albumin. Despite its large cationic charge and many apolar (—CH2—CH2—CH2—CH2—) side chains, polylysine shows very weak affinity for anions. Polyvinylpyrrolidone is more effective but not impressive. 

The solubility of polymers is, for thermodynamic reasons, more restricted than the solubility of low-molecular compounds and, consequently, the choice of solvents is limited. Potential solvents for most synthetic polymers are of moderate polarity. Alcohols and liquids of similar polarity are precipitants for many synthetic polymers. The search for a mobile phase that enables RPC through solvophobic interactions between the polymer and the nonpolar stationary phase requires attempts to make the mobile phase an unfavorable environment for the solute. This easily conflicts with the narrow limits of solubility of the polymer under investigation. Solubility effects are known to occur even in low-molecular RPC 92 94), but in polymer RPC they even may govern retention. 

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