Meet the 2018 Beijing Scholars
Ritvik Bodducherla, North Carolina School of Science and Mathematics
Hometown: Charlotte, NC
Project: Development of an Antiproliferative Drug Utilizing Ellagic-Acid Loaded Mesoporous Silica Nanoparticles
Abstract: With the rise of cancer-related deaths and the inefficiency of current chemotherapeutic treatments, a new solution is necessary. Ellagic acid, a fruit-based phenolic compound that has anti-bacterial, anti-viral, and anti-cancerous uses, is the ideal answer. However, it is difficult to administer ellagic acid for medicinal uses because it is quickly metabolized into urolithins once ingested. Thus, this research aims to first verify ellagic acid’s potency as a cancer inhibitor and then develop ellagic acid as a viable drug agent by utilizing mesoporous silica nanoparticles as carriers for delivery. In this project, ellagic acid’s inhibitory efficiency was first computationally determined by observing binding affinities to VEGFR-2, TGF-β1, and some Matrix Metalloproteinases, among other targets. After having shown that ellagic acid could be an effective anti-cancerous agent, a sample of mesoporous silica nanoparticles (MSNs) was synthesized, ellagic acid was loaded into them, and the bacterial inhibition of the loaded mesoporous silica nanoparticles was then compared to that of pure ellagic acid. The computations are suggestive of ellagic acid being a strong angiogenic inhibitor in vivo. The computational and experimental results together exhibit that the developed drug can successfully inhibit cancerous enzymes, and that mesoporous silica nanoparticles will carry and deliver ellagic acid successfully and efficiently without leakage to become a more effective anti-cancer treatment than those existing.
Elizabeth Farmer, North Carolina School of Science and Mathematics
Hometown: Chapel HIll, NC
Harmful Algal Growth Suppressed by Allelopathy Regardless of Excess Phosphorus
Abstract: Harmful algal blooms (HAB) plague eutrophic waters and are often caused by excess anthropogenic nutrients, specifically phosphorus. Allelopathy, a defense mechanism in which an organism excretes harmful chemicals, has been previously identified as a potential biological control method for HABs. The effect of varying nutrient levels on this allelopathy, however, has not been investigated. This study examined whether the allelopathy of the cyanobacterium (Microcystis aeruginosa) towards the green HAB alga (Chlorella) was impacted by varying phosphorus levels. This was tested by measuring the growth rate and final cell density of Chlorella under high or low phosphorus conditions, and one of the allelopathy treatments. The allelopathy treatments were: a negative control, live M. aeruginosa, or M. aeruginosa filtrate. Chlorella growth was significantly inhibited by phosphorus limitation, but further inhibited by the filtrate or live M. aeruginosa, even in the high phosphorus treatment. The results indicated that the effect of the allelopathy was stronger than the high phosphorus treatment and the allelopathy could override the benefit received by Chlorella from eutrophic growing conditions. This project demonstrates the effectiveness of allelopathy for HAB suppression in any phosphorus conditions, establishing a promising control for limiting the destructive and costly impacts of HABs.
Michelle Gan, Enloe High School
Hometown: Cary, NC
Project: Carbon Dioxide Dry Reforming Over Novel Pt Catalyst Created Using Unconventional Fabrication Method
Abstract: Global warming has become an increasingly prevalent and exigent global issue as the amount of greenhouse gases in the atmosphere continues to increase. As a result, dry reformation of methane (DRM) has become an appealing research topic among scientists. This is primarily due to DRM’s ability to transform a harmful and low-quality biogas (CO2 and CH4) into syngas (H2 and CO), an invaluable and more energetically efficient replacement for liquid fuel in many technological processes. Typical methods used to create metal catalysts for DRM and similar reactions require expensive and complex precursors of which there are limited options. In this research, we present a novel platinum catalyst created using an entirely new method that eludes the costs, inflexibilities, and constraints associated with standard fabrication techniques. We investigated the catalyst’s performance over an industrial-use temperature range and compared the results to the activity of other commercial and prominent metal catalysts. The catalyst endured several days of testing without undergoing deactivation. Our results display a substantial increase in activity at lower temperatures; these results are desired for industrial catalysis, as the catalyst is energetically more efficient at lower temperatures and able to forego activity-inhibiting coke deposition and sintering.
Kevin Jin, North Carolina School of Science and Mathematics
Hometown: Charlotte, NC
Project: Selective Recovery of Rare Earth Elements Utilizing Novel Liquid Membrane Processes
Abstract: Disposal of coal ash, also called coal combustion residue (CCR) which is a by‐product of incineration of coal and municipal solid wastes, is becoming an increasing economic and environmental burden, due to its abundance and its potential to leach toxic metals at disposal sites. Given coal’s role in heat generation, solving this problem is important. Thus, there’s a growing interest in looking for avenues where coal ash can be used as a potential resource for preparation of value‐added products.
Although CCR can be utilized in cementitious products like highway road bases, the rate of production of coal ash far exceeds the rate of consumption. CCR has another potential use as a source for rare earth elements (REEs). REEs consist of the yttrium, scandium, and the lanthanide series; they’re not found in nature as pure metals and must be isolated from host minerals and are very valuable. REEs are useful because they are critical in automotive, energy, electronics, and defense industries, especially in new technological developments. With the recent instabilities in the REE global market, it is important to establish the potential for alternative sources of REEs. Sourcing, or recovering, REEs from CCRs has advantages when compared to traditional recovery methods of REE ores. CCRs are a readily available waste product, require money to safely dispose of otherwise, and do not require extensive, environmentally‐destructive excavation. Additionally, CCR is a fine powder which is ideal for chemical processing compared to costly ore processing steps of REE ores. There is also a lot of potential value in the REE content of coal ash. The value of the REEs present in CCRs is very high, particularly with scandium. This total value of REEs is estimated to be around 4 billion dollars in the USA. The beneficial outcome for recovering metals from CCRs is promising; this necessitates the development of methods for greater utilization and production of high-value compounds from this waste.
The classical method to extract metals from CCR solids includes acid digestion. After the acid digest, the solid residue is filtered and washed, which can achieve low concentrations of trace elements. However, the effectiveness of this method is low, as certain compounds are less affected by acid treatment, but this method also extracts all the metal ions present in the residue, while only REEs are desired.
I designed two phases to overcome this disadvantage and then demonstrate the feasibility in the selected recovery of rare earth elements. This design was based on previous liquid membranes that have recovered ions from a solution. Liquid emulsion membranes (LEM) and supported liquid membranes (SLM) are liquid membrane methods that have been used to recover metal cations from aqueous mixtures.
Phase 1 studies the kinetics of the REE leaching from coal ash to determine key parameters that are efficient and effective to reach an equilibrium of REE extraction, which is ideal for the following selected recovery.
Phase 2 designs and tests selective recovery methods to optimally recover REEs from CCRs utilizing hydro metallurgical-based methods of liquid membrane processes.