ISSN 1063-7745, Crystallography Reports, 2006, Vol. 51, No. 5, pp. 863–869. © Pleiades Publishing, Inc., 2006. Original Russian Text © T.V. Bukreeva, B.V. Parakhonsky, A.G. Skirtach, A.S. Susha, G.B. Sukhorukov, 2006, published in Kristallografiya, 2006, Vol. 51, No. 5, pp. 920–926. 863 INTRODUCTION At present, considerable progress has been achieved in encapsulation at the micrometer level. Microcap- sules have been used in pharmaceutical, cosmetic, food, textile, and agricultural branches of industry. The use of these systems holds great promise in pharmaceu- tics because they are capable of delivering drugs to a desired place in an organism at a specified instant of time in an adequate concentration. A number of prob- lems in this field have been solved to date, for example, the use of gelatin microcapsules to protect orally administered drugs from the action of acids in the stomach before the drugs’ adsorption in the intesti- nal tract [1]. Another solved problem is associated with prolonged action of a drug (for example, an analgesic) due to the slow decomposition of a poly- mer in the intestinal tract during the use of capsules prepared from alginate or a copolymer of lactic and glycolic acids [2]. In some cases, the target delivery of a drug without loss is required, followed by its activation under spe- cific internal or external actions. Nowadays, research on the use of microwave or laser radiation for these pur- poses is being performed intensively; however, the problem regarding microcapsules remains unsolved. Recently, it has been proposed to solve this problem with the use of polyelectrolyte capsules whose walls involve metal nanoparticles [3, 4]. The technique proposed a few years ago for produc- ing polyelectrolyte shells on colloidal particles of a dif- ferent nature is one of the most promising tools for fab- ricating microcapsules [5–7]. According to this tech- nique, multilayer shells a few nanometers in thickness are prepared on the surface of spherical particles (tem- plates), whose sizes vary from several hundred nanom- eters to tens of micrometers, through the sequential adsorption of oppositely charged polyelectrolyte mac- romolecules. In this case, templates are prepared from latex, SiO 2 , calcium carbonate, and magnesium car- NANOMATERIALS AND CERAMICS Dedicated to the 60th Birthday of M. V. Kovalchuk Preparation of Polyelectrolyte Microcapsules with Silver and Gold Nanoparticles in a Shell and the Remote Destruction of Microcapsules under Laser Irradiation T. V. Bukreeva a , B. V. Parakhonsky a, b , A. G. Skirtach c , A. S. Susha d , and G. B. Sukhorukov a, e a Shubnikov Institute of Crystallography, Russian Academy of Sciences, Leninskiœ pr. 59, Moscow, 119333 Russia e-mail: bukreeva@ns.crys.ras.ru b Moscow State University, Leninskie gory, Moscow, 119992 Russia c Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, 14424 Germany e-mail: gleb@mpikg-golm.mpg.de d Photonics and Optoelectronics Group Physics Department and Center for Nanoscience (CeNS), Ludwig-Maximilian University of Munchen, Munchen, D-80799 Germany e IRC/Department of Materials, Queen Mary University of London, Mile End Road, London, E1 4NS, United Kingdom Received February 28, 2006 Abstract—A number of methods are proposed for encapsulating silver and gold nanoparticles into shells of polyelectrolyte microcapsules for the purpose of increasing the sensitivity of microcapsules to laser radiation. It is shown that capsules with nanocomposite shells can be remotely damaged under laser radiation with differ- ent powers and wavelengths. The sensitivity of capsules with silver and gold nanoparticles in shells to this radi- ation can be controlled by varying the conditions used for the preparation of the capsules. The release of the encapsulated material under laser radiation makes these systems promising for use as microcontainers intended for the target delivery of drugs in an organism. PACS numbers: 78.67.Bf DOI: 10.1134/S1063774506050178