Solvent diffusion method

A similar technique, the so-called spontaneous emulsification solvent diffusion method, is derived from the solvent injection method to prepare liposomes [161]. Kawashima et al. [162] used a mixed-solvent system of methylene chloride and acetone to prepare PLGA nanoparticles. The addition of the water-miscible solvent acetone results in nanoparticles in the submicrometer range this is not possible with only the water-immiscible organic solvent. The addition of acetone decreases the interfacial tension between the organic and the aqueous phase and, in addition, results in the perturbation of the droplet interface because of the rapid diffusion of acetone into the aqueous phase. 

T Niwa, H Takeuchi, T Hino, N Kunou, Y Kawa-shima. Preparations of biodegradable nanospheres of water-soluble and insoluble drugs with d,l-lacti-de/glycolide copolymer by a novel spontaneous emulsification solvent diffusion method, and the drug release behavior. J Control Rel 25 89-98, 1993. 

Hu F.Q. et al.. Preparation of solid lipid nanoparticles with clobetasol propionate by a novel solvent diffusion method in aqueous system and physicochemical characterization, Int. J. Pharm., 239, 121, 2002. 

Spontaneous emulsification and solvent diffusion method Solid lipid nanoparticles 20-80 nm Horn and Rieger, 2001 Cui et al., 2006 Ribeiro et al., 2008... 

The simplest approach is to have the two reactant solutions as layers in direct contact, one above the other, just like the solvent diffusion method in Section 1.28.4. This only works when the two solutions differ significantly in density, which usually means they have different solvents otherwise the initial separation can not be achieved and mixing is too rapid. 

Usually, either room temperature solvent diffusion methods or higher-temperature (T < 200°C, autogeneous pressure) solvothermal conditions are used to condense the... 

Re, M.I., Biscans, B., 1999. Preparation of microsphere of ketoprofen with acrylic polymers by a quasi emulsion solvent diffusion method. Powder Technology 101 (2), 120—133. 

Kawashima Y, Iwamoto T, Niwa T, Takeuchi H, Hino T. Role of the solvent-diffusion-rate modifier in a new emulsion solvent diffusion method for preparation of ketoprofen microspheres. Journal of Microencapsulation. July-September 1993 10(3) 329-340. PubMed PMID 8377091. 

Kawashima Y, Niwa T, Handa T, Takeuchi H, Iwamoto T, Itoh K. Preparation of controlled-release microspheres of ibuprofen with acrylic polymers by a novel quasi-emulsion solvent diffusion method. Journal of Pharmaceutical Sciences. January 1989 78(1) 68-72. PubMed PMID 2709323. 

Gao Y, Cui FD, Guan Y, Yang L, Wang YS, Zhang LN. Preparation of roxithromycin-polymeric microspheres by the emulsion solvent diffusion method for taste masking. International Journal of Pharmaceutics. August 2, 2006 318(l-2) 62-69. PubMed PMID 16647230. 

T Niwa. H Takeuchi. T Hino. N Kunon, Y Kawashima. In-vitro drug release behaviour of D.L-laciide/glycolide copolymer (Plga) nanospheres with nafarelin acetate prepared by a novel spontaneous emulsification, solvent diffusion method. J. Pharm. Sci. 83 727-732. 1994. 

Sato Y, Kawashima Y, Takeuchi H (2003) Physicochemical properties to determine the buoyancy of hollow microspheres (microballoons) prepared by the solvent diffusion method. Eur J Pharm Biopharm 55 297-304... 

Murakami H, Kobayashi M, Takeuchi H et al (1999) Preparation of poly (d, L-lactide-co-glycolide) nanoparticles by modified spontaneous emulsification solvent diffusion method. IntJ Pharm 187 143-152... 

PEG-coated nanospheres were also prepared by the solvent diffusion method by using water-miscible organic solvents, such as acetone (Bazile et... 

The salting-out procedure can be considered as a modification of the emulsification/solvent diffusion method. The technique is based on the salting out of water miscible solvents from aqueous solution containing electrolyte salts such as calcium chloride, magnesium acetate or sucrose. Pol)mier and drug are initially... 

Preparation of Carvedilol Spherical Crystals Having Solid Dispersion Structure by the Emulsion Solvent Diffusion Method and Evaluation of Its in vitro Characteristics... 

Spherical agglomeration has got more importance than other methods because it is easy to operate and the selection of the solvents is easier than in the other methods. Quasi emulsion solvent diffusion method has the second importance. 

Cur F., Yang M., Jiang Y., Cun D., Lin W., Fan Y., Kawashima Y (2003). Design of sustained-release nitrendipine microspheres having solid dispersion structure by quasiemulsion solvent diffusion method. Journal of ControlledRelease, 91,375-384. 

Tapas, A.R., Kawtikwar, P.S., Sakarkar, D.M. (2009). Enhanced dissolution rate of felodipine using spherical agglomeration with Inutec SPT by quasi emulsion solvent diffusion method. Research in Pharmaceutical Sciences, 4, 77-84. 

J. You, ED. Cui, X. Han, Y.S. Wang, L. Yang, Y.W. Yu, O.P. Li, Study of the preparation of sustained release microspheres containing zedoary turmeric oil by the emulsion solvent diffusion method and evaluation of the self emulsification and bioavailabihty of the oil. Colloids SurfB Biointerfaces, 48 35-41,2006. 

Yang MS, Cui FD, Yon BG, Fan YL, Wang L, Yue P, Yang H. 2003. Preparation of sustained-release nitrendipine microspheres with Eudragit RS and Aerosil using quasiemulsion solvent diffusion method. IntJ Pharm 259 103-113. 

---