Applications factors influencing barrier properties

Excipients can influence delivery from topical and transdermal medications. The propensity of the drug to migrate from the formulation to the application surface is affected by factors such as lipophilicity of the vehicle, drug solubility in the formulation, and effects of additives on the barrier properties of the skin or mucosal surface. 

From the results it is clear that no residues were found up to the sensitivity limit of the analytical methods used. Furthermore untreated leaves were found to contain practically no radioactive material. It can be concluded that diflubenzuron after application on plants is very persistent and has no systemic properties. In other studies it was found that diflubenzuron does not permeate through the cuticular barrier into the leaves of broad bean. These studies on the fate of diflubenzuron on and in plants will be published more extensively elsewhere ( J ) Essentially the same results were obtained by Still in a study on the metabolic fate of diflubenzuron on cotton plants ( 2). In addition to metabolism, other factors might influence the fate of diflubenzuron on plants, i.e. washing off and photochemical degradation. Ruzo et al. (jQ) and Metcalf et al. (30)... 

In contrast to most other uses, lead-acid storage batteries have largely maintained, if not extended, their market position and range of applications in recent years. For the SLI market, especially, the lead-acid battery technology has several advantages over other alternative systems, in terms of both cost and performance (where lead s specific electrical and chemical properties are a crucial factor). The main influences here, as we have seen, have been technical changes which have improved battery performance, but economised on lead usage per battery. A further barrier to the introduction of any new, alternative SLI battery technolc is the widespread and weU-estab-lished infrastructure that already exists to produce and recycle lead-acid batteries. 

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