Employment of nanomaterials in polymerase chain reaction: insight into the impacts and putative operating mechanisms of nano-additives in PCR

The unique ability to rapidly amplify low copy number DNA has made in vitro Polymerase Chain Reaction one of the most fundamental techniques in modern biology. In order to harness this technique to its full potential, certain obstacles such as nonspecific by-products, low yield and complexity of GC rich and long genomic DNA amplification need to be surmounted. As in vitro PCR does not have any regulatory mechanisms unlike its counterpart in vivo DNA replication machinery, scientists often use a number of additives like glycerol, betaine, dimethyl sulphoxide and formamide in order to achieve the perfection of in vivo systems. In the last two decades nanotechnology has provided excellent solutions to many classical problems in various scientific fields including biotechnology and recently the PCR technique has begun to benefit from this so called “Nano Era”. In this review, the impacts of several nanomaterials on PCR efficiency, specificity and fidelity are described in accordance with the recent literature. Putative interaction mechanisms between nanomaterials and primary PCR components are also addressed in a comprehensive manner

Nucleation dynamics of water nanodroplets

The origin of the condensation of water begins at the nanoscale, a length-scale that is challenging to probe for liquids. In this work we directly image heterogeneous nucleation of water nanodroplets by in situ transmission electron microscopy. Using gold nanoparticles bound to a flat surface as heterogeneous nucleation sites, we observe nucleation and growth of water nanodroplets. The growth of nanodroplet radii follows the power law: R(t)similar to(t-t(0)), where similar to 0.2-0.3

Experimental evidence and theoretical analysis of nanobubble stability within graphene nanoscrolls

In this study direct observation and dynamics of nanoscale water and nanobubbleswithin graphene nanoscrolls were reported. The life time of these nanobubbles is much higher than expected, which we propose is due to the combination of several factors including localized heating and surface charge. The stability of the nanobubbles within graphene nanoscrolls has been theoretically analyzed. The nanobubbles inside these nanoscrolls reveal a wide distribution of graphene-water contact angles. Bubble dynamics within these graphene nanochannels was directly observed and recorded

Graphene integrated polymeric membranes for ultrafiltration

Graphene has the potential to re-define the pore parameters of a conventional ultrafiltration membrane. Due to its flexibility, mechanical strength and atomic thickness, graphene provides a platform for nano/sub nanometer pores for ionic filtration. In this work we would like to present the mechanisms involved in graphene integration/transfer with a polymer substrate, the overall effects of graphene on the properties of the membrane and initial results on textile dye filtration using these membranes. In addition we also would like to present how water nanodroplets can be live imaged under a Transmission Electron Microscope (TEM) using graphene as a TEM window. This method can pave a way for new generation nanofluidic devices where bio-molecules can be imaged in their natural state. Nanodroplet condensation and water bubble dynamics have been observed and recorded by this method

Protein mediated textile dye filtration using graphene oxide-polysulfone composite membranes

Here we report graphene oxide (GO) concentration dependent protein binding (BSA) and dye filtration (RO-16) capabilities of polysulfone-GO composite membranes under different pH conditions (2, 7 and 10). The membranes were fabricated with different GO concentrations (1, 2, 4 and 8% w/w) and were successfully characterized for their physical and chemical properties, as well as for their performance ability. The best BSA binding and dye rejection rates were observed with 2% GO membrane at pH = 10, which were 95% and 78.26% respectively, suggesting that 2% is the optimal concentration. Further, considering the fact that RO-16 dye is acidic friendly, contact time studies were carried out with 2% GO membranes at pH = 2 and pH = 10. It was observed that 2% GO-polysulfone membrane at pH = 2 shows the highest dye rejection rate of 87.4%, supporting the importance of contact time in filtration technology