Peña-Rodríguez and Pal Nanoscale Research Letters 2011, 6:279 http://www.nanoscalereslett.com/content/6/1/279 Conclusions By manipulating structural parameters of bimetallic MDM (DCN) structures, a gain in intensity of ω− − mode up to 20 (60) percent can be achieved over their Au-only counterparts in the region of transparency of human tissues. The condition for such gains is that the outer metal layer has a thickness in the range of 5 to 10 nm; in this configuration the internal and external energy modes are closer, so that the interaction between them is greater and, consequently, both have some cross-influence over the hybridized modes. Thus, the ω− energy mode “inherits” the spectral position of the − energy mode of the outer metallic layer and the inten- sity of the inner one. Our designed bimetallic nanos- tructures could be more suitable than the conventional mono metallic nanoparticles and nanoshell structures for SERS and cancer therapy applications. Abbreviations DCN: double concentric nanoshell; MDM: metal-dielectric-metal; NPs: nanoparticles; SERS: surface enhanced Raman scattering; SPR: surface plasmon resonance. Acknowledgements O. Peña-Rodríguez thanks DGAPA-UNAM and ICMAB-CSIC for extending a postdoctoral fellowship through the UNAM-CSIC agreement. Author details 1Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, Bellaterra, Barcelona, 08193, Spain 2Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48, Puebla, Puebla 72570, México Authors’ contributions OPR conceived the study, performed the calculations and participated in the analysis of the results and writing the manuscript. UP supervised the study and participated in the analysis of the results and writing the manuscript. All authors read and approved the manuscript. Competing interests The authors declare that they have no competing interests. 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