Synergistic acceleration in the osteogenesis of human mesenchymal stem cells by graphene oxide-calcium phosphate nanocomposites.

Nanocomposites consisting of oblong ultrathin plate shaped calcium phosphate nanoparticles and graphene oxide microflakes were synthesized and have demonstrated markedly synergistic effect in accelerating stem cell differentiation to osteoblasts.

New functional amorphous calcium phosphate nanocomposites by enzyme-assisted biomineralization.

In the present study, we report on enzyme-assisted formation of biomineralized amorphous calcium phosphate nanocomposites (ACP-NCs). About 100-200 nm sizes of the spherical porous enzyme-assisted ACP-NCs were successfully synthesized via double reverse microemulsion, but no ACP-NCs formed without the enzyme. It is believed that the enzyme was used as an organic template or additive that could regulate the biomineralization process.

Electrospun polystyrene-poly(styrene-co-maleic anhydride) nanofiber as a new aptasensor platform.

Here, we report the use of an aptamer-immobilized electrospun polystyrene-poly(styrene-co-maleic anhydride) (PS-PSMA) nanofiber as a new aptasensor platform for protein detection. Two thrombin-binding aptamers (TBA29 and TBA15) were used as a model platform to facilitate efficient detection of thrombin in a sandwich manner. Thrombin concentration was measured by fluorescence microscopy and spectroscopy, in which aptamers were labeled with either fluorescein dye or quantum dots.

Immobilization-free screening of aptamers assisted by graphene oxide.

Graphene oxide (GO) has the ability to separate free short ssDNA in heterogeneous solution. This feature is applied as a label free platform for screening of aptamers that bind to their target with high affinity and specificity. Herein, we report an aptamer selection strategy for Nampt protein based on GO.

Determination of the size of water-soluble nanoparticles and quantum dots by field-flow fractionation.

Field flow fractionation (FFF) technique is used to determine the size of water-soluble Au, ZnS, ZnS-Mn2+ nanoparticles, and CdSe, CdSe-DNA quantum dots (QDs). The results of the FFF measurements are compared with the particle size analysis using conventional techniques like scanning electron microscopy (SEM), transmission electron microscopy (TEM), and dynamic light scattering (DLS) studies. Water-soluble gold nanoparticles (AuNPs) stabilized by mercaptosuccinic acid (MSA) as the ligand when analyzed by the SEM and DLS showed evidence of extensive aggregation, preventing an accurate determination of the average particle size.

Monitoring of petroleum hydrocarbon degradative potential of indigenous microorganisms in ozonated soil.

This study was performed to investigate the petroleum hydrocarbon (PH) degradative potential of indigenous microorganisms in ozonated soil to better develop combined pre-ozonation/bioremediation technology. Diesel-contaminated soils were ozonated for 0-900 min. PH and microbial concentrations in the soils decreased with increased ozonation time.

Comparative analysis of vertical heterogeneity of microbial community in sulfur-packed reactor used for autotrophic nitrate removal.

To better understand microbial community in sulfur-based nitrate removal process, comparative molecular analyses were performed with the biofilm formed on sulfur particles that were obtained from different bed-heights of a laboratory-scale reactor employed for the process. Microbial community in the reactor showed vertical heterogeneity in terms of total cell count and nitrate removal activity. DAPI (4',6-diamidino-2-phenylindole) staining revealed that total cell count (per g sulfur particle) gradually decreased as bed height increased until reaching approximately middle of the reactor bed, showing a nearly plateau afterward.