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A series of new visible and near-infrared (NIR) luminescent lanthanide-hydroxybenz[de]anthracen derivatives (Ln(HBAN)(3)(H(2)O)(2)(NO(3))(3), Ln(HBAN)(3)phen(NO(3))(3)) were synthesized (HBAN-6-hydroxybenz[de]anthracen-7-one, Ln=Eu, Yb, Nd). Further, chemically bonded lanthanide hybrids of functionalized mesoporous silica (SBA-15) are prepared using HBAN-functionalized alkoxysilane (HBAN-Si) as linker, which is named as Ln(HBAN-SBA-15)(3)(NO(3))(3), Ln(HBAN-SBA-15)(3)phen(NO(3))(3) (Ln=Eu, Yb, Nd), respectively. The physical characterization and especially the photoluminescence properties for these hybrids are performed. SAXRD and BET of them revealed that all of these hybrid materials have uniformity in the mesostructure. Worth noting here is that the excitation spectra of these hybrid materials are extended to visible light region (439-535 nm). Upon ligand-mediated excitation with the ultraviolet and visible light, the visible luminescence for europium hybrids and NIR luminescence for Yb(3+) and Nd(3+) hybrids are obtained., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Free gold nanoparticles easily aggregate when the environment conditions change. Here, gold nanoparticles (AuNPs) with average diameter of 3.7 nm were prepared and then modified with poly(ethylene glycol) (PEG) to improve stability. The gold nanoparticles were first surface-modified with 3-mercaptopropionic acid (MPA) to form a self-assembled monolayer and subsequently conjugated with NH(2)-PEG-NH(2) through amidation between the amine end groups on PEG and the carboxylic acid groups on the particles. The biocompatibility and intracellular fate of PEG-modified gold nanoparticles (AuNP@MPA-PEG) were then studied in human cervical cancer (HeLa) cells. Cell viability test showed that AuNP@MPA-PEG did not induce obvious cytotoxicity. Both confocal laser scanning microscopy and transmission electron microscopy demonstrated that AuNP@MPA-PEG entered into mammalian cells and the cellular uptake of AuNP@MPA-PEG was time-dependent. Inductively coupled plasma mass spectrometry and confocal microscopy imaging further demonstrated that AuNP@MPA-PEG penetrated into the nucleus of mammalian cells upon exposure for 24 h. These results suggest that surface modification can enhance the stability and improve the biocompatibility. This study also indicates that AuNP@MPA-PEG can be used as potential nuclear targeted drug delivery carrier.