Biological inertness

Denture Adhesives. Fast hydration and gel-forming properties are ideally mated to produce a thick, cushioning fluid between the dentures and gums (100). The biologically inert nature of poly(ethylene oxide) helps reduce unpleasant odors and taste in this type of personal-care product (see... 

An overview of silica in biological systems is available (9). Silica is chemically inert, and in bulk it is relatively biologically inert. It is listed in the U.S. Food... 

Polymeric drugs are macromolecules that elicit biological activity (7). Many synthetic polymers are biologically inert. However, some exhibit toxicity, while others exhibit a wide range of therapeutic activities. There are three kinds of polymer drugs polycations, polyanions, and polynucleotides. 

The important attributes of liposomes as a drug carrier are (a) they are biologically inert and completely biodegradable (b) they pose no concerns of toxicity, antigenicity, or pyrogenicity, because phospholipids are natural components of all cell membranes (c) they can be prepared in various sizes, compositions, surface charges, and so forth, depending on the requirements of... 

This subject can be considered in terms of five different types of molecules or materials (a) biologically inert, water-insoluble polymers (b) water-insoluble polymers that bear biologically active surface groups (c) water-swellable polymeric gels, or amphiphilic polymers that function as membranes (d) water-insoluble but bioerodable polymers that erode in aqueous media with concurrent release of a linked or entrapped bioactive molecule and (e) water-soluble polymers that bear bioactive agents as side groups. 

Solubility/miscibility Insoluble in ethanol. Soluble to twice its weight (2 x grams) in water (xml). Soluble in glycerol and propylene glycol Biological considerations Virtually biologically inert Chemical compatibility/Stability considerations None Uses (routes) Orally, as diluent or viscosity increaser in solvents... 

Biological activity Designed for biological activity Strive for biological inertness... 

Although pigments, because they are practically insoluble in water and — if at all — only sparingly soluble in common solvents, are largely biologically inert, it is the responsibility of the pigment manufacturer and producer to comply with legal requirements. 

PET itself is biologically inert if ingested and is dermally safe during handling. No adverse effects have been observed at exposures anticipated to occur from the use of PET packages (International Life Sciences Institute, 2000). It poses no hazard if inhaled and no evidence of toxicity has been detected in feeding studies using animals. 

Fig. 12.8 Distributions of parathion in (A) biologically-inert (sterile) Gilat soil (20% moisture content, 1.4 g cm bulk density) after 3.03 days, and (B) biologically-active Gilat soil (34% soil moisture content, 1.4 g cm bulk density) after 2, 4 and 7 days. The solid curves were calculated using D= 1.67x 10 cm s the points represent experimental measurements (Gerstl et al. 1979a)...

In vivo feeding experiments with singly and doubly labeled strictosidine (33) in C. roseus shoots afforded labeled ajmalicine (39), serpentine (40), vindoline (3), and catharanthine (4). Vincoside (85, page 37) was not incorporated into the alkaloids, suggesting that it was biologically inert 188). Brown and co-workers 190) conducted somewhat parallel studies examining the precursor relationship of strictosidine in C. roseus. Incorporation into tetrahydroalstonine (75), ajmalicine (39), catharanthine (4), and vindoline (3) was observed. 

Stability The marker for GFR measurement should be biologically inert, which implies the absence of binding to plasma proteins, reabsorption in the renal tubule, deleterious effect on renal function, and intact excretion of the filtrate in the urine without degradation. This biological inert criterion, albeit difficult to achieve synthetically, confers an enormous advantage for speedy regulatory approval, especially if small doses are used. 

Solid platinum wire or foil is considered to be biologically inert. ... 

Toxicology. Silicon appears to be a biologically inert material. 

Siloxanes are the most extensively used synthetic biomaterial due to several reasons such as flexibility, chemical and biological inertness, low capacity to bring about blood clotting, overall low degree of biological toxicity, and good stability within biological environments. 

It should be emphasized that it is the combination of biological inertness and unmatched gas-dissolving capacity of PFCs that creates the potential for an injectable oxygen carrier. Likewise, it is the combination of their inertness and... 

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