Capsule composition

Wanlian Pharmaceutical Co. Rifaximin Soft Capsule Composition. Patent No. CN1451386,2002. 

In conclusion, controllable inorganic precipitation can be performed exclusively inside polyelectrolyte capsules forming the hollow composite structure. Capsules bearing material with certain properties (conductivity, magnetic susceptibility, etc.) can find practical applications in novel micron-scale electronic and optoelectronic devices, drug delivery, microreactors for spatially restricted catalytic chemical and biochemical synthesis. The influence of micron-scale volume and capsule composition on chemical reactions in capsule interior is a subject for further investigations. 

Rebck and coworkers extended their studies on the hydrogen-bond-based self-assembly of tetrameric capsules around guest molecules using a combinatorial approach. Starting from two different monomers, a small dynamic library of guest-filled capsules was produced. The distribution of capsule compositions was analyzed by MS and found to depend on the nature of the guest, with methylquinuclidinium cation as the most... 

Keywords ATRP Capsules Composite materials Controlled radical polymerization Emulsion polymerization Encapsulation Inorganic particles Miniemulsion polymerization NMP RAFT... 

The different salts, esters, ethers, isomers, mixtures of isomers, complexes or derivatives of an active substance shall be considered to be the same active substance, unless they differ significantly in properties with regard to safety and/or efficacy, in which case additional safety and efficacy data are required. The same qualitative and quantitative composition only applies to the active ingredients. Differences in excipients will be accepted unless there is concern that they may substantially alter the safety or efficacy. The same pharmaceutical form must take into account both the form in which it is presented and the form in which it is administered. Various immediate-release oral forms, which would include tablets, capsules, oral solutions and suspensions, shall be considered the same pharmaceutical form for this purpose. 

There are a variety of routes currently utilized to fabricate a wide range of hollow capsules of various compositions. Among the more traditional methods are nozzle reactor processes, emnlsion/phase-separation procednres (often combined with sol-gel processing), and sacrificial core techniques [78], Self-assembly is an elegant and attractive approach for the preparation of hollow capsules. Vesicles [79,80], dendrimers [81,82], and block hollow copolymer spheres [83,84] are all examples of self-assembled hollow containers that are promising for the encapsnlation of various materials. 

The foregoing examples show that hollow polymer capsules with varying composition and sizes of ca. 2-20 micrometers can be produced, either by templating charged (latex particles and biocrystals) or uncharged (organic microcrystals), and that different core removal procedures can be employed. Nanometer-size polymer capsules have also been produced by employing smaller particle templates [107]. 

The foregoing results demonstrate that the thickness of the capsule wall can be controlled at the nanometer level by varying the number of deposition cycles, while the shell size and shape are predetermined by the dimensions of the templating colloid employed. This approach has recently been used to produce hollow iron oxide, magnetic, and heterocomposite capsules [108], The fabrication of these and related capsules is expected to open up new areas of applications, particularly since the technology of self-assembly and colloidal templating allows unprecedented control over the geometry, size, diameter, wall thickness, and composition of the hollow capsules. This provides a means to tailor then-properties to meet the criteria of certain applications. 

FIG. 13 TEM micrograph of a hollow composite nanoparticle/polymer capsule dried on a carbon grid. The hollow composite capsule was obtained after removal of the ME core from Si02/PDAD-MAC-coated ME particles by treatment with hydrochloric acid. The shadowing seen is a result of collapse and overlapping of the hollow capsule upon drying. (From Ref. 110.)... 

Although capsules made from gelatin predominate, recent years have seen an increased interest in and availability of nongelatin capsules. Such alternative shell compositions may satisfy religious, cultural, or vegetarian needs to avoid animal sources. Hard shell capsules made from starch were developed by... 

A Ludwig, M Van Ooteghem. Disintegration of hard gelatin capsules. Part 5 the influence of the composition of the test solution on disintegration of hard gelatin capsules. Pharm Ind 43 188-190, 1981. 

The benefit of the LbL technique is that the properties of the assemblies, such as thickness, composition, and function, can be tuned by varying the layer number, the species deposited, and the assembly conditions. Further, this technique can be readily transferred from planar substrates (e.g., silicon and quartz slides) [53,54] to three-dimensional substrates with various morphologies and structures, such as colloids [55] and biological cells [56]. Application of the LbL technique to colloids provides a simple and effective method to prepare core-shell particles, and hollow capsules, after removal of the sacrificial core template particles. The properties of the capsules prepared by the LbL procedure, such as diameter, shell thickness and permeability, can be readily adjusted through selection of the core size, the layer number, and the nature of the species deposited [57]. Such capsules are ideal candidates for applications in the areas of drug delivery, sensing, and catalysis [48-51,57]. 

Polymer Composition (Inner/Outer/Co ating) Membrane Method of Type Capsule Formation Observations... 

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