Figure 4.

Photoluminescence spectra of a as-synthesized NPs and b APTES-coated NPs (λex = 280 nm). Images of optical phantoms containing 5 mg/mL as-synthesized NPs a inset and APTES-coated NPs, b insetem = 575 - 650 nm).

Sun et al. Nanoscale Res Lett 2011 6:24   doi:10.1007/s11671-010-9768-x