Microencapsulation complex coacervation

Qv, X. Y., Zeng, Z. P. Jiang, J. G. (2011). Preparation of lutein microencapsulation by complex coacervation method and its physicochemical properties and stability. Food Hydrocolloids, Vol. 25, 6, (August 2011), pp. (1596-1603), ISSN 0268-005X... 

The typical microencapsulation process via complex coacervation is illustrated in Figure 6.7. 

Keywords Bio artificial pancreas, biomaterials, complex coacervation, immunoisolation, microencapsulation, polyelectrolytes, water soluble polymers. 

Several other investigators have reported microencapsulation methods based upon polyelectrolyte complexes [289, 343]. For example, oppositely-charged polyelectrolytes (Amberlite IR120-P (cationic) and Amberlite IR-400 (anionic)) were recently used along with acacia and albumin to form complex coacervates for controlled release microcapsule formations [343]. Tsai and Levy [344,345] produced submicron microcapsules by interfacial crosslinking of aqueous polyethylene imine) and an organic solution of poly(2,6 dimethyl... 

Ducel, V., Richard, J., Saulnier, P., Popineau, Y., Boury, F. (2004). Evidence and characterization of complex coacervates containing plant proteins applications to the microencapsulation of oil droplets. Colloids and Surfaces A Physicochemical and Engineering Aspects, 232, 239-247. 

Xing, F., Cheng, G., Yang, B., Ma, F. (2004). Microencapsulation of capsaicin by the complex coacervation of gelatin, acacia and tannins. Journal of Applied Polymer Science, 91,2669-2675. 

The coacervation method is one of the earliest microencapsulation techniques, which has been used for various consumer products. This method is based on separation of a solution of hydrophilic polymer(s) into two phases, which are small droplets of a dense polymer-rich phase and a dilute liquid phase. Coacervation can be divided into simple and complex coacervation depending on the number of polymers that are involved in the formation of microparticles. 

Pahnieri, G.F. Lauri, D. Martelli, S. Wehrle, P. Methoxy-butropate microencapsulation by gelatin-acacia complex coacervation. Drug Dev. Ind. Pharm. 1999, 25 (4), 399-407. 

Nevertheless we have chosen an alternative approach microencapsulation using synthetic polyacrylates which may be stronger and more biocompatible (or at least have a more reproducible biocompatibility). Most of the effort has been with a particular water insoluble synthetic copolymer (HEMA-MMA), although other polyacrylates (water soluble or insoluble) have been used. In general, two approaches have been used complex coacervation with water soluble polycations and polyanions to generate an insoluble complex and simple coacervation with a water insoluble polymer precipitated from an organic solvent. 

The development of early encapsulation technology and preparation of microcapsules dates back to 1950s when Green and coworkers produced microencapsulated dyes by complex coacervation of gelatin and gum Arabic, for the manufacture of carbonless copying paper. The technologies developed for carbonless copy paper have led to the development of various microcapsule products in later years. 

Arneodo, C.J.F. Microencapsulation by complex coacervation at ambient temperature. FR 2732240 Al,... 

Thies, C. Microencapsulation of flavors by complex coacervation. In Lakkis, J.M. (d) Encapsulation and Controlled Release Technologies in Eood Systems, Blackwell Publishing, Ames, lA, 2007, pp. 149-170. 

Rocha-Selmi, G.A., Theodora, A.C., Thomazini, M., Bolini, H.M.A., and Favaro-Trindade, C.S. Double emulsion stage prior to complex coacervation process for microencapsulation of sweetener sucralose. Journal of Food Engineering 119(1) (2013) 28-32. 

Comunian T, Thomazini M, Alves A, Matos-Jr, F, Balieiro J, Favaro-Trindade C (2013) Microencapsulation of ascorbic acid by complex coacervation Protection and controlled. Food Research International 1 373-379. 

There are many complex coacervation systans suitable for microencapsulation. Most of them use gelatin as the cationic polymer to interact with a wide range of anionic polymers to form coacervates. 

FIGURE 12.4 Flow diagram of a typical microencapsulation process based on complex coacervation of gelatin and gum arabic. 

There have been excellent reviews published in recent years as related to gelatin replacement for microencapsulation. Table 12.2 lists some of the examples of non-gelatin based complex coacervation systems. Proteins derived from plants, such as pea protein, - wheat protein," ° soy protein, whey protein from dairy products, " chitosan from marine crustaceans, and collagen have been used to replace gelatin in complex coacervation. 

Since the first commercial application to carbonless copy paper in the 1950s, microencapsulation with coacervation technology has been successfully applied to many other areas, such as food, pharmaceuticals, cosmetics, biotechnology, and agrochemicals. The capsules provide such functions as controlled release, taste masking, improved heat and oxidative stability, reduced volatility/ flammability/toxicity, separation of reactive incompatibles, improved shelf-life, conversion of liquids to solids, and improved flowability as well as material handling. Among various coacervation processes, complex coacervation is most prevalent. 

Microencapsulation with complex coacervation has many advantages. It can produce capsules with a payload as high as 95%. The wall of the microcapsules is non-water soluble when it is either cross-linked with chemicals or treated with heat. This is a significant advantage over the microcapsules prepared with other technologies, such as spray drying or fluid bed coating by which the microcapsule wall produced is often water soluble. The microcapsules produced have excellent oxidation stability at low relative humidity, and core release can be initiated by different mechanisms. 

McMullen, J. N., D. W. Newton, and C. H. Becker, Pectin-gelatin complex coacervates II Effect of microencapsulated sulfamerazine on size, morphology, recovery, and extraction of water-dispersible microglobules. J. Pharm. ScL, 73(12) (1984) 1799-1803. 

Piacentini,E., L. Giorno,M. M.Dragosavac, G. T. Vlasdisavljevic, andR.G.Holdich,Microencapsulation of oil droplets using cold water fish gelatine/gum arabic complex coacervation by membrane emulsification. Food Res. Int., 53(1) (2013) 362-372. 

Mendanha,D.V.,S.E.M.Ortiz,C.S.Favaro-Trindade,A.Mauri,E.S.Monterrey-Quintero,andM.Thomazini, Microencapsulation of casein hydrolysate by complex coacervation with SPI/pectin. Food Res. Int., 42 (2009) 1099-1104. 

Nori,M.P.,C.S.Favaro-Trindade,S.M.Alencar,S.M.Thomazini,andJ.C.C.Balieiro,Microencapsulation of propolis extract by complex coacervation. Food Sci. TechnoL, 44 (2010) 429-435. 

Xiao, J.-X., H.-Y. Yu, and J. Yang, Microencapsulation of sweet orange oil by complex coacervation with soybean protein isolate/gum arabic. Food Chem., 125 (2011) 1267-1272. 

Lazko, J., Y. Popineau, D. Renard, and J. Legrand, Microcapsules based on glycinin glycinin-sodium dodecyl sulfate complex coacervation. J. Microencapsul., 21 (2004) 59-70. 

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