Manipulation of gold colloidal nanoparticles with atomic force microscopy in dynamic mode: influence of particle–substrate chemistry and morphology, and of operating conditions

• Samer Darwich,
• Karine Mougin,
• Akshata Rao,
• Enrico Gnecco,
• Shrisudersan Jayaraman and
• Hamidou Haidara

Beilstein J. Nanotechnol. 2011, 2, 85–98, doi:10.3762/bjnano.2.10

• coated with methyl (–CH3) and hydroxyl (–OH) terminated thiol groups. This major result suggests that the adhesion of the particles to the substrate is strongly reduced by the presence of hydrophobic interfaces. The influence of critical parameters on the manipulation was investigated and discussed viz

• illustrated in Figure 5a. This series of experiments was performed on a Veeco AFM whose tip follows a zigzag scan path. The role of the hydrophobic or hydrophilic character of the interface in the manipulation process was investigated, using gold nanoparticles bearing OH- and CH3-terminated thiol groups (as

• methyl-thiol-stabilized gold nanoparticles were synthesized according to a modified version of two common syntheses [21]. The as-synthesized nanosphere solution [27][28] was centrifuged at 7000 rpm for 20 min to pellet the nanoparticles, decanted, and then re-suspended in 1 mL of deionized water to

Magnetic nanoparticles for biomedical NMR-based diagnostics

• Huilin Shao,
• Tae-Jong Yoon,
• Monty Liong,
• Ralph Weissleder and
• Hakho Lee

Beilstein J. Nanotechnol. 2010, 1, 142–154, doi:10.3762/bjnano.1.17

• epichlorohydrin and activated by ammonia to provide primary amine group functionality. The amine groups can then be easily reacted with various agents containing anhydride, hydroxyl, carboxyl, thiol, or epoxide groups, to confer molecular specificity to the nanoparticle through bioconjugation [43]. Amine

• . This sequence served as a linker, binding both an avidin-conjugated CLIO population (via the biotin/avidin interaction) as well as a second CLIO population (via the thiol provided by the terminal cysteine on the peptide) [13]. The subsequent addition of caspase-3 disassembled the aggregates by cleaving

Sensing surface PEGylation with microcantilevers

• Natalija Backmann,
• Natascha Kappeler,
• Thomas Braun,
• François Huber,
• Hans-Peter Lang,
• Christoph Gerber and
• Roderick Y. H. Lim

Beilstein J. Nanotechnol. 2010, 1, 3–13, doi:10.3762/bjnano.1.2

• surface PEGylation, and (2) conformational changes in the PEG layer over a timescale of tens of minutes in situ. Specifically, thiol-terminated PEG (mPEG–SH, 20 kDa) chains have been covalently tethered onto Au-coated microcantilever surfaces by the “grafting to” approach. When switching between good

• (polyethylene glycol) thiol 20000 (mPEG–SH, MW ~ 20000) was purchased from Laysan Bio Inc (Arab, AL). (1-Mercapto-11-undecyl)tetra(ethylene glycol) (EG4–C11–SH, MW ~ 380.5) was obtained from Asemblon Inc (Seattle, WA), diluted in ethanol to an end concentration of 10 mM and stored at +4 °C. Coating of