Capsule-based systems

Capsules do noi have lo be inserted in a proper orientation, as in all other capsule based systems. 

An example of a nanocomposite with an additional function in the material is self-healing systems. Capsule-based systems that have the healing agents included in cavities in the polymer matrix are one type of self-healing materials. 

Bateman SD, Verlin J, Russo M, Guillot M, Laughlin SM. The development and validation of a capsule formulation knowledge based system. Pharm Tech 1996 20(3) 174-84. 

A composition based on diketopiperazine derivatives (3,6-bis (N-fumaryl-N-(n-butyl) amino-2, 5-diketopiperazine) has been investigated as a pulmonary drug delivery system, termed Technospheres (Pharmaceutical Discovery Corp., Elmsford, NY) (Pohl et al. 2000 Steiner et al. 2002). The diketopiperazine derivatives self-assemble into microparticles at low pH with a mean diameter of approximately 2 pm. During self-assembly, diketopiperazine derivatives microencapsulate peptides present in the solution. Insulin incorporated in diketopiperazine derivatives (TI) was administered to five healthy humans by the use of a capsule-based inhaler with a passive powder deagglomeration mechanism. Relative and absolute bioavailability of TI in the first 3 hours (0-180 min) were 26 12% and 15 5%, and for 6 hours (0-360 min) 16 8% and 16 6%, respectively (Steiner et al. 2002). The time to peak action for glucose infusion rates was shorter with both IV (14 6 min) injection and inhalation (39 36 min), as compared to SC administration (163 25 min). This rapid absorption of insulin would be beneficial for diabetic patients who need to rapidly affect their glucose levels. 

The capsule concept was reviewed in detail by Legere and Salin [90, 91]. The sample is handled in an encapsulated form until it is in the digestion solvent. Operation of the capsule-based microwave-assisted digestion system proceeds in several steps, during which temperature and pressure are monitored. 

Legere, G., Salin, E.D. Capsule-based microwave digestion system. Appl. Spectrosc. 49, 14A-20A (1995)... 

Fig. 7 Capsule-based rupturing pulsatile delivery system. (From Ref.t l)...

Personnel at the Sanofi Research Division of Philadelphia recently developed an expert system for the formulation of hard gelatin capsules based on specific preformulation data of the active ingredient. Using Formulogic, the system generates one first-pass clinical capsule formulation with as many subsequent... 

Non-aqueous solvents and their mixtures Go-solvents Co-solvents, lipid based systems in soft or hard gelatin capsules... 

Surfactants and phospholipid in aqueous and non-aqueous media Micellar solubilization Lipid based systems in Liposome capsules... 

Fisons introduced the first DPI with the capsule-based Spinhaler . This was followed by a number of other capsule devices and then by unit dose blisters and multidose systems. DPIs are very diverse in their design and operation, since each product manufacturer has developed their own proprietary devices for their own drugs. 

Non-phospholipid based materials are also known to form vesicles or capsules. These systems include polymersomes (19, 20), cereasomes (21), and alginate-based capsules (22). However, each of the systems has drawbacks, which range from particle size to accessibility of substrates. To remove these... 

In the present section are covered capsules based on completely different hydrogen bond donor and acceptor, while calyx[4]arenes with similar systems like tosylurea and urea have been reported in Section 2.1.4... 

Mookhoek S.D., Fischer H.R.and van der Zwaag S. (2009), A numerical study into the effects of elongated capsules on the healing efficiency of liquid-based systems, Comp. Mat. ScL, 47(2), 506-511. 

A number of studies of the self-association features of TTF-C4P-based systems are ongoing presently in the Sessler and Jeppesen laboratories. The interested reader is advised to consult the current literature for updates that may arise as the result of these efforts. Based on what has been reported to date, it is clear that functionalized calixpyrroles have a role to play in the design and synthesis of stimulus-responsive supramolecular constructs, including capsules and self-assembled polymers. 

The recent literature on materials that can be classified as capable of autonomic healing csm be fiirther divided into sub-categories based on the self-healing concept employed. The subcategories include One-capsule systems, dual-capsule systems, and microvascular or fiber network-based systems. 

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