Seoktae Kang

We provide the first evidence that the size (diameter) of carbon nanotubes (CNTs) is a key factor governing their antibacterial effects and that the likely main CNT-cytotoxicity mechanism is cell membrane damage by direct contact with CNTs. Experiments with well-characterized single-walled carbon nanotubes (SWNTs) and multiwalled carbon nanotubes (MWNTs) demonstrate that SWNTs are much more toxic to bacteria than MWNTs. Gene expression data show that in the presence of both MWNTs and SWNTs, Esch

Rational modification of carbon nanotubes (CNTs) to isolate their specific physical and chemical properties will inform a mechanistic understanding of observed CNT toxicity in bacterial systems. The present study compares the toxicity of commercially obtained multiwalled carbon nanotubes (MWNTs) before and after physicochemical modification via common purification and functionalization routes, including dry oxidation, acid treatment functionalization, and annealing. Experimental results support

This study evaluates the cytotoxicity of four carbon-based nanomaterials (CBNs)--single-walled carbon nanotubes (SWNTs), multiwalled carbon nanotubes (MWNTs), aqueous phase C60 nanoparticles (aq-nC60), and colloidal graphite--in gram negative and gram positive bacteria. The potential impacts of CBNs on microorganisms in natural and engineered aquatic systems are also evaluated. SWNTs inactivate the highest percentage of cells in monocultures of Escherichia coli, Pseudomonas aeruginosa, Bacillus

Electrochemical CO2 reduction (CO2RR) has received much attention for its ability to generate value-added chemicals from a molecule that would otherwise be a waste end-product. Numerous studies have emerged in the past decades, but the renewable and sustainable carbon-neutral CO2 reduction process is yet to be industrialized. Here, we review the progress and bottlenecks of the electrochemical CO2 reduction technologies over the past 15 years (2004–2018) to examine whether CO2RR process is to be

We developed a method for preparing live bacterial cell probes for atomic force microscopy (AFM) using a bioinspired polydopamine wet adhesive. Microscopic examinations with bacterial and yeast cells indicated that cells were successfully glued to the end of the AFM cantilevers and remained viable for the duration of the force measurements. Interaction forces measured with live single-cell microorganism probes differed markedly from those obtained with glutaraldehyde-fixed microorganism probes.

Abstract The biofouling potential is one of the important factors to design and to select membranes for water and wastewater treatment. In this investigation, the effect of membrane surface properties during the attachment of S. cerevisiae cells was examined using a laboratory‐scale membrane filtration cell enabling direct microscopic observation of microbial cell deposition. The experimental results from 6 commercially available membranes showed that the initial adhesion rate, k d , was affecte

Decades of electrochemical CO2 reduction research have led to established rules about the product selectivity, i.e., bare tin yields formic acid as the main product. Here, we present Sn nanoparticles supported on carbon nanotubes (CNTs) in a hollow fiber (Sn-CHF), which produce CO with 10 times higher selectivity than formate. Density functional theory calculations reveal that a strong interfacial field induced by the carbon support enhances the rate-limiting CO2 adsorption and thus CO productio

In this study, expanded graphite (EG) was decorated with manganese oxide nanoparticles (MONPs) by the hydrothermal method, and the newly formed composite (MONPs-EG) was applied as adsorbent for the removal of heavy metals from aqueous solutions. The comparative and competitive adsorption of Pb2+ and Ni2+ (0.01–1.00 mM) on MONPs-EG was investigated. Data from isothermal adsorption of single and binary systems suggested that both Pb2+ and Ni2+ were well described by the Langmuir isotherm, and the