Nanocapsules encapsulation

In another approach, the polymer is precipitated from the continuous phase onto on stable nanodroplets in an inverse miniemulsion [109], In this case, a miniemulsion with the liquid core material is formed in a continuous phase that consists of a mixture of a solvent and a nonsolvent for the polymer. That way, PMMA nanocapsules encapsulating an antiseptic agent could be produced. 

Lboutoimne, H., Charlet, JT., Ploton, C., Flason, F., and Pirot, E., Sustained ex vivo skin antiseptic activity of chlorhexidine in polyfepsilon-caprolactone) nanocapsule encapsulated form and as a digluconate, J. Control Release, 82 (2 3), 319-334, 2002. 

Kitajyo, Y, Nawa, Y, TamaM, M. et al. (2007a) A unimolecular nanocapsule Encapsulation property of amphiphilie polymer based on hyperbranched polythreitol. Polymer, 48,4683 690. 

Bae KH, Ha YJ, Kim C, Lee KR, Park TG (2008) Pluronic/chitosan shell cross-linked nanocapsules encapsulating magnetic nanoparticles. J Biomater Sci Polym Ed 19 (12) 1571-1583... 

Table 1. Formation of filled nanocapsules. Elements in shadowed boxes are those which were encapsulated so far. M and C under the chemical symbols represent that the trapped elements are in metallic and carbide phases, respectively. Numbers above the symbols show references.

Having already examined the use of the LbL method to make various nanocapsules, including polymer nanocapsules, and having already encountered the use of star polymers for catalyst encapsulation, we turn our attention to other methods for the formation of polymeric nanocapsules. Useful reviews of the formation of these capsules using various methods are available [78-84]. 

However, it has to be realized that biological templates remain inserted in the final nanoparticles and this is not acceptable for many applications. Nevertheless, some recent examples indicate that such biomimetic materials may be suitable for the design of biotechnological and medical devices [32]. For instance, it was shown that silica gels formed in the presence of p-R5 were excellent host matrices for enzyme encapsulation [33]. In parallel, biopolymer/silica hybrid macro-, micro- and nanocapsules were recently obtained via biomimetic routes and these exhibit promising properties for the design of drug delivery materials (see Section 3.1.1) [34,35],... 

Muller, A., Das, S.K., Kogerler, P., Bogge, H., Schunemann, V., Krickmeyer, E. and Preetz, W. (2000) A new type of supramolecular compound molybdenum-oxide-based composites consisting of nanocapsules with encapsulated keggin-ion electron reservoirs cross-linked to a two-dimensional network. Angewandte Chemie-Intemational Edition, 39, 3413-3417. 

Nanocapsule A spherical particle of submicrometer diameter consisting of an outer polymeric wall which encapsulates an inner core. 

One approach to compartmentalize hemoglobin is to encapsulate hemoglobin in biodegradable polymer-PEG-polylactide (30). These nanocapsules have a diameter of 80-150 nm and contain superoxide dismutase, catalase, carbonic anhydrase, and other enzymes of Embden-Meyerhof pathway that are needed for long-term function of an oxygen carrier (31,32). The polylactide capsules are metabolized in vivo to water and carbon... 

Sukhomkov GB, Antipov AA, Voigt A, Donath E, Mohwald H. pH-Controlled macromolecule encapsulation in and release from polyelectrol3de multilayer nanocapsules. Macromol Rapid Commun 2001 22 44-46. 

When the core is an oily liquid, the surrounding polymer is a single layer of polymer, and the vesicle is referred to as a nanocapsule. These systems have found utility in the encapsulation and delivery of hydrophobic drugs Polymers used for the formation of nanocapsules have typically included polyester homopolymers such as poly(D,L-lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) and poly(caprolactone) PCL [112],... 

Frey and Van Koten et al. [40-42] reported on the noncovalent encapsulation of sulfonated pincer-platinum(II) complexes in readily available amphiphilic nanocapsules based on hyperbranched polyglycerol, possessing a reverse micelle-type architecture. The incorporated platinum(II) complexes showed catalytic activity in a double Michael addition, albeit with decreased activities compared to the free pincer complex. Due to the size of... 

Fig. 12 a Molecular nanocapsule synthesis, structure, and non covalent encapsulation of platinum pincer complexes in the hydrophilic interior... 

Fig. 12 b Preparation of chiral molecular nanocapsules 15 and 16 with Bis(2,3-di-hydroxypropyl)-10-undecenylamine and trimethylolpropane (TMP), Respectively, and a schematic encapsulation of sulfonated platinum pincer complexes of type 3 in the hydrophilic compartment of the nanocapsules... 

In this context, the chiral hyperbranched polyglycerols (-)-PG [Mn = 3000, with bis(2,3-dihydroxypropyl)undecenylamine as the initiator] and (+)-PG [Mn = 5500, with trimethylolpropane (TMP) as the initiator] were used. Esterification of the hydroxyl groups of these hyperbranched polyglycerols with hydrophobic alkyl chains as palmitoyl chloride, yielded amphiphilic molecular nanocapsules with reverse micelle-type architecture, in which approximately 50% of the hydroxyl groups were functionalized with palmitoyl chains [96-98]. These materials exhibit low polydispersity (Mw/Mn < 2), and the amphiphilic molecular nanocapsules are soluble in nonpolar solvents and irreversibly encapsulate various polar, water-soluble dye molecules in their hydrophilic interior by liquid-liquid extraction [96,98]. 

The hydrophilic sulfonated NCN-pincer platinum complex [PtCl(NCN-SO3H)] was encapsulated by liquid-liquid extractions from an aqueous solution (0.5 M NaOH) into a dichloromethane solution of nanocapsules... 

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