Nanoscale & Nanoscale Advances Blog

Graphene-based materials have many applications due to their interesting electronic and mechanical properties. Part of the typical process used to prepare graphene is the reduction of graphene oxide (GO), often using toxic and unstable hydrazine derivatives.

Now Boukherroub and co-workers report a method for the production of graphene nanosheets whereby GO is reduced by UV irradiation in aqueous solution. This was most successful in the presence of silicon nanowire arrays decorated with copper nanoparticles which act as photocatalysts.

The graphene nanosheets produced were free of contaminants and the authors believe the scalability of this process will be an advantage.

Read this HOT Nanoscale article in full:

Silicon nanowire arrays-induced graphene oxide reduction under UV irradiation
Ouarda Fellahi, Manash R. Das, Yannick Coffinier, Sabine Szunerits, Toufik Hadjersi, Mustapha Maamache and Rabah Boukherroub
Nanoscale, 2011
DOI: 10.1039/C1NR10970G

Scientists from India have made blood compatible “hybrid quantum clusters” (HQCs) by combining fluorescent gold clusters with iron-containing superparamagnetic nanoparticles.

They found that the HQCs were capable of selective separation of cancer cells in blood or saline using an external magnet. The fact that the clusters are fluorescent means they can be imaged.

The authors hope their system could one day be used for a dialysis-type set up for cancer therapy.

Read this HOT Nanoscale article in full:

Fluorescent and superparamagnetic hybrid quantum clusters for magnetic separation and imaging of cancer cells from blood
C. V. Durgadas, Chandra P. Sharma and K. Sreenivasan
Nanoscale, 2011
DOI: 10.1039/C1NR10900F

Copper has been identified as a critical factor in Alzheimer’s disease due to its involvement in amyloid-β (Aβ) related toxicity, although the mechanism for this has not been understood.

Now Yan-Mei Li and co-workers have shown that while copper does not affect Aβ40, it significantly affects the aggregation Aβ42, enhancing the cytotoxicity of this protein. Aβ42 forms strong interactions with the copper causing it to change conformation to form highly toxic Aβ42 oligomers.

Stopping these Aβ42–copper interactions could therefore provide a promising therapy for Alzheimer’s disease.

Read this HOT Nanoscale article in full:

Copper inducing Aβ42 rather than Aβ40 nanoscale oligomer formation is the key process for Aβ neurotoxicity
Lu Jin, Wei-Hui Wu, Qiu-Ye Li, Yu-Fen Zhao and Yan-Mei Li
Nanoscale, 2011
DOI: 10.1039/C1NR11029B

Single walled carbon nanotubes (SWNTs) hold much promise for biomedical applications due to their unique optical response upon absorption of near-IR light.

In order to make these SWNTs biocompatible, scientists in Japan have designed a SWNT/DNA hybrid which can be coated with cationic poly(L-lysine) grafted with polyethylene glycol. The overall system shows good uptake in cells compared to the same system in the absence of polyethylene glycol.

The authors are now extending their experiments to a mouse cancer model.

Read this HOT Nanoscale article in full:

Enhanced cell uptake via non-covalent decollation of a single-walled carbon nanotube-DNA hybrid with polyethylene glycol-grafted poly(L-lysine) labeled with an Alexa-dye and its efficient uptake in a cancer cell
Tsuyohiko Fujigaya, Yuki Yamamoto, Arihiro Kano, Atsushi Maruyama and Naotoshi Nakashima
Nanoscale, 2011
DOI: 10.1039/C1NR10635J

Spherical silica micro/nanomaterials have great potential to be used as carriers in biological medical and catalytic applications.

In their Nanoscale review article Xin Du and Junhui He describe recent developments in the synthesis of these materials, discuss their applications and look forward to the challenges of the future in this exciting research field.

Read this HOT Nanoscale review:

Spherical silica micro/nanomaterials with hierarchical structures: Synthesis and applications
Xin Du and Junhui He
Nanoscale, 2011
DOI: 10.1039/C1NR10660K

The modification of gold nanoparticles using a specific number of strands of DNA allows them to be manipulated in a more controlled manner. In their interesting Feature article Liu et al. discuss developments in this approach and offer some perspectives on future challenges and opportunities in the field.

Read the full Feature article:

DNA discrete modified gold nanoparticles
Tao Zhang, Zhongqiang Yang and Dongsheng Liu
Nanoscale, 2011
DOI: 10.1039/C1NR10882D