Generation of Monodisperse Particles by Using Microfluidics: Control over Size, Shape, and Composition

We failed to reference the interesting and relevant work of Gañán-Calvo and co-workers: A. M. Gañán-Calvo, Phys. Rev. Lett. 1998, 80, 285; A. M. Gañán-Calvo, J. M. Gordillo, Phys. Rev. Lett. 2001, 87, 274 501; I. G. Loscertales, A. Barrero, I. Guerrero, R. Cortijo, M. Marquez, A. M. Gañán-Calvo, Science 2002, 295, 1695. We would also like to point the interested reader to other relevant reports, such as: I. Cohen, H. Li, J. L. Hougland, M. Mrksich, S. R. Nagel, Science 2001, 292, 265; S. Sugiura, M. Nakajima, H. Itou, M. Seki, Macromol. Rapid. Commun. 2001, 22, 773; T. Nisisako, T. Torii, T. Higuchi, Chem. Eng. J. 2004, 101, 23. Although the details of the fluid physics and the specific applications of our paper differ from those of the reports cited herein, the prior work of these authors illustrates the value of flow-focusing systems in making highly uniform droplets and the potential for using these droplets in materials science. In addition, following the submission of our report, two other articles that document the use of microfluidic channels for the in situ preparation of anisotropic polymeric particles were published: W. Jeong, J. Kim, S. Kim, S. Lee, G. Mensing, D. J. Beebe, Lab Chip 2004, 4, 576; D. Dendukuri, K. Tsoi, T. A. Hatton, P. S. Doyle, Langmuir 2005, 21, 2113.