Elution drugs

It is often easier to elute drugs from silica than from either cellulose or alumina, and only bonded stationary phases should be used in reversed-phase systems or else the organic stationary phase will also be eluted. These points should be considered when choosing the stationary phase. 

Abbott Absorb bioresorbable stent, which elutes drugs and resorbs naturally into the body leaving no scaffold. 

T artrazine, 4,5-dihydro-5 -oxo-1 -(4-sulfophenyl)-4-[(4-sulfophenyl)azo]-1// -pyrazole-3-carboxylic acid trisodium salt was discovered by Ziegler in 1884 and is used as a dye for wool and silk. It is used as a colour additive in foods, drugs and cosmetics, and is an adsorption-elution indicator for chloride estimations in biochemistry (B-76MI40404). 

In order to illustrate the critical process parameters of SMB process validation, we will consider the separation of the racemic drug as described in Process design. The study represents the effect of the influence of feed concentration, number of plates and retention factor on the second eluting enantiomer. The simulation of the process for different values of feed concentration is performed and the variations of the extract and raffinate purities are shown in Fig. 10.10. 

Wash the SPE tube packing with three 200-/a1 aliquots of water, dry it with nitrogen for 5 min, and elute the drugs with three 100-ju-1 aliquots of 90 parts ethanol and 10 parts diethyl ether. Concentrate the recovered drugs by evaporating some or all of the solvent before analysis by GC/MS. (See Supelco Bulletin 810B.)... 

Table 11.1. Fragmentation and elution order of underivatized drugs ...

The separation was carried out on a bonded phase LC-PCN column carrying cyanopropylmethyl moieties on the surface. Thus, in contrast to the extraction process, which appears to be based on ionic interactions with the weak ion exchange material, the LC separation appears to be based on a mixture of interactions. There will be dispersive interactions of the drugs with the hydrocarbon chains of the bonded moiety and also weakly polar interactions with the cyano group. It is seen that the extraction procedures are very efficient and all the tricyclic antidepressant drugs are eluted discretely. 

Ranade, S.V. et al. Physical characterization of controlled release of pacUtaxel from the TAXUS Express 2 drug-eluting stent, J. Biomed. Mater. Res., 71 A, 625, 2004. 

FIGURE 4.5 A 72-year-old man with medical history remarkable for hypertension and dyslipidemia presented with posterior circulation infarct (a). CTA and posterior circulation angiography (left vertebral artery injection) performed demonstrated severe mid-basilar artery stenosis (b and c). Left vertebral artery injection demonstrated near-complete reversal of the stenosis after a drug-eluting balloon expandable stent (Cypher, Cordis Johnson Johnson) was deployed (d). 

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