Controlled release typical applications

The widespread applicability of di-O-methylisosorbide as a medium for chemical reactions or as a solvent for pharmaceutical formulations is well documented. In some cases, an additive synergism of the solvent and the solute was observed. Some typical examples mentioned include that it acts as a solvent for muscle-relaxant drugs, which are otherwise difficultly soluble,226 and is used for topical and other types of pharmaceutical formulations,227,228 transdermal controlled-release films229 and tapes,230 anthelmintic solutions,231 antimycotic emulsions,232 and for the treatment of skin disorders, such as eczema.233... 

A lean NOx trap (LNT) (or NOx adsorber) is similar to a three-way catalyst. However, part of the catalyst contains some sorbent components which can store NOx. Unlike catalysts, which involve continuous conversion, a trap stores NO and (primarily) N02 under lean exhaust conditions and releases and catalytically reduces them to nitrogen under rich conditions. The shift from lean to rich combustion, and vice versa, is achieved by a dedicated fuel control strategy. Typical sorbents include barium and rare earth metals (e.g. yttrium). An LNT does not require a separate reagent (urea) for NOx reduction and hence has an advantage over SCR. However, the urea infrastructure has now developed in Europe and USA, and SCR has become the system of choice for diesel vehicles because of its easier control and better long-term performance compared with LNT. NOx adsorbers have, however, found application in GDI engines where lower NOx-reduction efficiencies are required, and the switch between the lean and rich modes for regeneration is easier to achieve. 

Is a controlled-release system required This question will primarily relate to systemic drug delivery applications, typically for potent drugs such as steroid sex hormones and, perhaps, peptides or peptidomimetic agents. 

Fassihi R, Fabian J, Sakr AM. Application of response surface methodology to design optimization in formulation of a typical controlled release system. Drugs Made Ger 1996 39(Oct-Dec) 122-126. 

Hollow spheres are a typical stmcture of CPCs, which in particular have a wide number of potential applications, including stationary phases for separation science, biomedical devices, coating additives, controlled-release reservoirs, and encapsulation. In fact, the multifunctionality of hollow spheres of CPs is an important subject in the field of materials science. 

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