Functionalized Polycarbonate Commercial Filters for Water Purification

Can commerercially available filtration membranes be easily functionalized in such a way to enhence the removal the charged contaminants in the water treatment process? The literature demonstrates there have been two pioneering works that demonstrated that Ultrathin Self-Assembled Nanoparticle (USANP) membranes (composed of ~5 nm diameter metallic gold nanoparticles surrounded by organic ligands) when applied to commercial membranes displayed charge sensitive rejection to molecular dyes and also have the ability to charge modify the openings in commercial filters. The rejection mechanisms in these works are proposed to be either size dependent or charged based. Recent experimental results have demonstrated that the supporting filter for these USANP membranes can be functionalized solely with highly charged molecular dye Direct Red 80 using no USANP membranes. After functionalization with direct red 80 alone, average rejection for tested molecular dyes at a concentration of 145 µM increased from 31.8 % to 85.6 % even without the addition of a USANP layer. This indicates that dyes themselves are capable of functionalizing the commercial membranes providing an additional method to enhanced rejection of charged contaminants. This poster highlights the efforts made by a Preservice and Early Career Research for Teachers (PERT) team and an Undergraduate student who was awarded an Summer Undergraduate Research Experience Award to measure the rejection results of these two different functionalization methods. Knowledge gained from these experiments may allow for enhanced rejection of charged based contaminants in polluted waters

Azo-Dye-Functionalized Polycarbonate Membranes for Textile Dye and Nitrate Ion Removal

Challenges exist in the wastewater treatment of dyes produced by the world’s growing textiles industry. Common problems facing traditional wastewater treatments include low retention values and breaking the chemical bonds of some dye molecules, which in some cases can release byproducts that can be more harmful than the original dye. This research illustrates that track-etched polycarbonate filtration membranes with 100-nanometer diameter holes can be functionalized with azo dye direct red 80 at 1000 µM, creating a filter that can then be used to remove the entire negatively charged azo dye molecule for a 50 µM solution of the same dye, with a rejection value of 96.4 ± 1.4%, at a stable flow rate of 114 ± 5 µL/min post-functionalization. Post-functionalization, Na+ and NO3− ions had on average 17.9%, 26.0%, and 31.1% rejection for 750, 500, and 250 µM sodium nitrate solutions, respectively, at an average flow rate of 177 ± 5 µL/min. Post-functionalization, similar 50 µM azo dyes had increases in rejection from 26.3% to 53.2%. Rejection measurements were made using ultraviolet visible-light spectroscopy for dyes, and concentration meters using ion selective electrodes for Na+ and NO3− ions

Stratospheric ozone depletion and plant-insect interactions: Effects of UVB radiation of generalist and specialist herbivores on a tropical tree and a temperate forb

I investigated effects of UVB radiation on plant-insect interactions using two plant-herbivore systems.Treatment of Citrus jambhiri cuttings with elevated levels of UVB radiation (\rm10\ kJ\ m\sp{-2}d\sp{-1}\ UVB\ BE\sb{300}) increased the ratio of psoralen to bergapten in leaves. Furanocoumarin content varied according to leaf age. Phototoxicity of leaf extracts paralleled the furanocoumarin content of leaves. ANCOVA showed that leaf age-dependent phototoxicity could be accounted for on the basis of furanocoumarin content.Rooted C. jambhiri cuttings were grown at \rm6.4\ kJ\ m\sp{-2}d\sp{-1}\ UVB. Furanocoumarins levels increased in irradiated plants and the increase of psoralen was greatest in young leaves. A generalist, Trichoplusia ni, was reared on artificial diets amended with furanocoumarins at ecologically relevant concentrations with and without supplemental UVB radiation. UVB radiation and dietary furanocoumarins caused severe mortality while furanocoumarins alone caused developmental delay with some treatment groups recovering from this delay in later development. Caterpillars reared on potted citrus cuttings under UVB radiation exhibited a similar developmental delay. Survivorship was also decreased.Using UVB levels of 6 and 12 kJ, I reared a specialist, Junonia coenia on excised leaves, potted plants, and artificial diet. No direct or indirect effects of UVB were observed on the development or survivorship of this specialist. A parallel set of experiments was conducted with the generalist. Elevated UVB radiation lowered the survivorship of T. ni reared on diet. Development of larvae reared on excised leaves was more rapid on young leaves from plants receiving enhanced UVB radiation. Caterpillars reared on potted plants developed more slowly when caterpillars were reared on plants growing at elevated UVB, indicating that the performance enhancing effects of UVB radiation seen in excised leaves were overridden in whole plants.Iridoid glycoside levels in Plantago lanceolata were unchanged but elevated UVB increased concentrations of verbascosides in young leaves. Allocation of above-ground biomass was altered; amounts of storage and reproductive biomass decreased when exposed to elevated UVB. Increasing herbivory was associated with decreased plant biomass.UVB decreased inflorescence number when plants were grown at 3.2 and 6.4 kJ.U of I OnlyETDs are only available to UIUC Users without author permissio

Azo dye functionalized polycarbonate membranes for textile dye and nitrate ion removal - Data and Supplementary Material

The dataset for the article Azo dye functionalized polycarbonate membranes for textile dye and nitrate ion removal is posted here along with videos that show the top and side views of the experiment.https://mds.marshall.edu/physics_data/1000/thumbnail.jp

Deconstructing Lipid Kinase Inhibitors by Chemical Proteomics

Diacylglycerol kinases (DGKs) regulate lipid metabolism and cell signaling through ATP-dependent phosphorylation of diacylglycerol to biosynthesize phosphatidic acid. Selective chemical probes for studying DGKs are currently lacking and are needed to annotate isoform-specific functions of these elusive lipid kinases. Previously, we explored fragment-based approaches to discover a core fragment of DGK-α (DGKα) inhibitors responsible for selective binding to the DGKα active site. Here, we utilize quantitative chemical proteomics to deconstruct widely used DGKα inhibitors to identify structural regions mediating off-target activity. We tested the activity of a fragment (RLM001) derived from a nucleotide-like region found in the DGKα inhibitors R59022 and ritanserin and discovered that RLM001 mimics ATP in its ability to broadly compete at ATP-binding sites of DGKα as well as >60 native ATP-binding proteins (kinases and ATPases) detected in cell proteomes. Equipotent inhibition of activity-based probe labeling by RLM001 supports a contiguous ligand-binding site composed of C1, DAGKc, and DAGKa domains in the DGKα active site. Given the lack of available crystal structures of DGKs, our studies highlight the utility of chemical proteomics in revealing active-site features of lipid kinases to enable development of inhibitors with enhanced selectivity against the human proteome