Platinum polymer

Fig. 7. Comparison of experimental phase boundary concentrations between the isotropic and biphasic regions for various liquid-crystalline polymer solutions with the scaled particle theory for wormlike hard spherocylinders. ( ) schizophyllan water [65] (A) poly y-benzyl L-glutamate) (PBLG)-dimethylformamide (DMF) [66-69] (A) PBLG-m-cresoI [70] ( ) PBLG-dioxane [71] (O) PBLG-methylene chloride [71] (o) po y(n-hexyl isocyanate) (PHICH°Iuene at 10,25,30,40 °C [64] (O) PHIC-dichloromethane (DCM) at 20 °C [64] (5) a po y(yne)-platinum polymer (PYPt)-tuchIoroethane (TCE) [33] ( ) (hydroxypropyl)-cellulose (HPC)-water [34] ( ) HPC-dimethylacetamide (DMAc) [34] (N) (acetoxypropyl) cellulose (APC)-dibutylphthalate (DBP) [35] ( ) cellulose triacetate (CTA)-trifluoroacetic acid [72]...

Recently, experimental data of S for various liquid-crystalline polymer solutions have become available. Figure 12 illustrates the concentration dependence of S for three polymer liquid crystal systems (a) PBLG-DMF [92,93], (b) PHIC-toluene [94], and (c) poly(yne)-platinum polymer (PYPt)-trichloro-ethane (TCE) [33]. For systems (a) and (c), with the alignment made by... 

The Pti samples (182) were prepared as colloids, protected by a PVP polymer film. Layer statistics according to the NMR layer model (Eqs. 28-30) for samples with x = 0,0.2, and 0.8 are shown in Fig. 63. The metal/ polymer films were loaded into glass tubes and closed with simple stoppers. The NMR spectrum and spin lattice relaxation times of the pure platinum polymer-protected particles are practically the same as those in clean-surface oxide-supported catalysts of similar dispersion. This comparison implies that the interaction of the polymer with the surface platinums is weak and/or restricted to a small number of sites. The spectrum predicted by using the layer distribution from Fig. 63 and the Gaussians from Fig. 48 show s qualitative agreement w ith the observed spectrum for x = 0 (Fig. 64a). 

Table 4. Toxicity of Platinum Polymers on Human Amnion Cells In Culture. (WISH)...

Which of these four potential advantages, if any, actually occurs with the platinum polymers is currently being studied. Approximately two dozen platinum polyamines have been synthesized, and some show biological activity while others do not (126-128). Several of the polymers properties are being explored and correlated with polymer activity in an effort to discover why certain polymers are active while others are inactive. Such factors as the nature of the diamine component, the extent to which a polymer is transported into the cell, the rate of aquation, etc., could all influence the biological activity of a polymer. Two other properties that could control polymer activity are the size of a polymer and the tendency of a polymer to degrade, and these will be the subject of discussion here. 

Although the platinum polymers share many properties with cis-DDP. one important difference between the two types of compounds has been uncovered and is indicated in Table 2. The biological activity of cis-DDP depends upon the age of the solution. A freshly prepared solution of cis-DDP in either dimethyl sulfoxide or cell culture medium is 100-fold more active than a solution which has been stored for several months. This loss of activity is presumably due to the reaction of cis-DDP... 

The molecular weights of the platinum polymers could influence their biological activity in two different ways. 

Figure 6. Elution profiles for platinum polymers. One milliliter of a polymer solution in dimethyl sulfoxide was loaded onto a 2.0 X 20 cm Sephacryl S-200 column. Fractions of 0.5 ml were collected and the absorbances determined. Elution profiles for (a) a 0.1% solution of polymer 18 (folic acid) and (b) a 0.05% solution of polymer 21 (tilorone) are shown.

Some cancers are believed to have a viral relationship. As such it is informative to look at the viral response to some of the platinum polymers. 

Recently, we looked at the ability of methotrexate, tetrachloroplatinate, a physical mixture of methotrexate and tetrachloroplatinate and a methotrexate-platinum polymers to inhibit various viruses. A related study employing tilorone and a tilor-one derivative and cisplatin polymeric derivatives was carried out. The results will be briefly reported later. For these studies each ceU line is especially chosen to be compatible to support growth for the particular virus. DSC-1 cells are African green monkey kidney epithehal cells, mouse L929 are fibroblast cells, vero cells are African green monkey kidney epithelial cells, and human 143 cells are fibroblast bone osteosarcoma cells. 

Structures of the platinum polymers are presented in Schanes 8.32 and 8.33. Each is a ds-derivative obeying the trans-effect. 

Platinum/Polymer Coat Decreased sensitivity increased response time Reduction in aging decreased movement artifact... 

Polymeric materials containing Pt—Pt bonds in their backbones have been examined (46). The formation of platinum polymers (23) was achieved via reaction of the platinum complex (21) with diacetylides, diphosphines, or diisocyanides (22) (eq. 7). 

Eor their exploitation at the anode of microbial BBSs, these compounds have to be oxidized at an electrocatalytic electrode surface. This anode concept has been used for the oxidation of hydrogen produced during glucose fermentation on a platinum polymer-based sandwich electrode. In a subsequent step, these noble metal-free materials were replaced by noble metal-free electrode electrocatalysts allowing the oxidation of not only H2 but also low-molecular organic acids such as formate and lactate [33-35]. furthermore, the exploitation of sulfur species [36-38] can be classified within this electron transfer concept, although it needs to be noted that sulfur species can be reversibly cycled over sulfide/sulfur in BESs [39]. 

Based upon these observations, the object of this study was to determine the effects of tetramisole, which is a mixture of levamisole and dextramisole, on the diabetogenesis of EMC-D virus in ICR Swiss male mice. Also, the effects upon the induction of EMC-D virus-mediated diabetes of platinum polymers of tetramisole was evaluated. 

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