Nanoparticles solvent displacement method

Figure 7 Ciclosporin A nanoparticles number average diameter 200 nm, prepared by a solvent displacement method (see Scheme 3). Source. From Ref. 72.

Nanocapsules act like a reservoir, which are called vesicular systems. They carry the active substance entrapped in the solid polymeric membrane or on their surfaces. The cavily inside contains either oil or water. A schematic diagram of Polymer Nanocapsules is shown in Fig. 9.2 [5], There are different methods that are used nowadays to prepare polymeric nanoparticles, such as nanoprecipitation (also termed as the solvent diffusion and solvent displacement method), solvent evaporation, dialysis, microemulsion, surfactant-free emulsion, salling-out, supercritical fluid technology, and interfacial polymerization [2]. Among these methods, nanoprecipitation is a fast and simple process, which does not require a pre-prepared polymer emulsion before the nanoparticle preparation. It produces a dispersion of nanoparticles by precipitation of preformed hydrophobic polymer solution. Under... 

F. 9.17 Solvent displacement method of nanoparticle formation based on the interfacial disturbances [7]... 

When using the last method, solvent displacement, also known as nanopredpitation, at first the polymer (together with the drug) is dissolved into a solvent, and then the solution is mixed with the antisolvent (usually water) [17]. In this stage, nanoparticles are spontaneously formed. As a last step, as in the previous method, the organic solvent should be eliminated by evaporation. 

Fig. 11 (A) SANS (dS/d l vs. Q) from selectively deuterated PLA(d)-PEG 3 5 nanoparticles at different solvent contrasts (a) 100% D20/0%H20 (b) 80%D20/20%H20 (c) 65%D20/35% H2O (vertically displaced). The continuous lines are a simultaneous fit of all three data sets using the best fit diffuse-shell model. (B) SANS (dS/dQ vs. Q) from selectively deuterated PLA(rf)-PEG 15 5 nanoparticles at different solvent contrasts (a) 100% D2O/0% H2O (b) 80% D2O/20% H2O (c) 65% D20/35% H2O (vertically displaced). The continuous lines are a simultaneous fit of all three data sets using the best-fit diffuse-shell model. (C) SANS (dS/dQ vs. Q) from selectively deuterated PLA(d)-PEG 45 5 nanoparticles at different solvent contrasts (a) 100% D20/0% H2O (b) 80% D20/20% H2O (c) 75% D20/25% H2O (vertically displaced). The continuous lines are a simultaneous fit of all three data sets using the best-fit diffuse well-established methods shell model. (Reproduced from Ref. l)...

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