Authors: J. Zhang, Y. Lu, M. Cao, H. Qin, M. Yamakawa, C. Dentinger, L. Nguyen, A.J. Chmura, J. Zhu, B. Lutz, K-B Sung, K. Swartz, L. Wang, X. Su, A.A. Berlin, S. Chan and L. Sun
Affilation: Intel Corporation, United States
Pages: 247 - 250
Keywords: SERS, nanoparticles, Raman, aggregation, encapsulation
Composite organic-inorganic nanoparticle (COIN) is a new type of optical label for multiplex biomolecule detection. It has strong Raman signal intensity and potentials for a large number of unique Raman signatures. We have developed methods to fabricate, to encapsulate, and to functionalize COINs. Our fabrication procedures take the advantage of the fact that the surface enhancement factor is greatest when the molecules are situated at the junctions of noble metal nanoparticles. Highly Raman active organic compounds (Raman labels) are selected and used to induce the cluster formation of gold or silver nanoparticles. Various types of organic compounds can be incorporated into the nanoclusters to produce COINs with distinctive Raman signatures. The aggregation kinetics and cluster size are controlled by the Raman label concentration, electrolyte addition, temperature and aggregation time. Once the clusters reach a desired size, a stabilizing agent such as bovine serum albumin (BSA) is added to stop further aggregation. The nanoparticles are subsequently encapsulated to enhance its stability; and then functionalized by biomolecules such as antibodies for application in biomolecule detection. Various analytical tools such as dynamic light scattering, zeta potential measurements, disc centrifugation are used to characterize the nanoparticles at different processing stages.