Wednesday, October 18, 2017

Students present at LSMCE conference

Analytical chemist Grace Muna accompanied three students to the 5th annual 2017 Louis Stokes Midwest Center of Excellence (LSMCE) Conference this October where she served as one of the judges for the student poster competition. Physics major E-Lexus Thornton (shown presenting his poster, above left) and Biology major Keon Jones (with Muna, above right) showcased their summer work under the LSAMP program at IU South Bend. Award-winning biochemistry major Michele Costantino also attended the conference to present her summer work under an REU at IUPUI. Presenting at a conference is a great way to end a project, like icing on a cake, but can also be a great way to start new beginnings by making contact with students and faculty from other institutes. Special thanks are due to these three students for representing IU South Bend and showing the Midwest states what quality students our campus has. Abstracts of the students' posters are given below.

Michele Costantino (Poster #55)
The effect of ionic solutions on surface potential of lipid membranes

Cellular membranes provide a barrier between two environments and are composed of a variety of lipid molecules. The composition of the membrane determines its function and as such can be influenced by ions and molecules in the surrounding environment. Amongst the factors affected is the electric charge and the surface potential (zeta potential) of the membrane. The mechanism by which the zeta potential of membranes is affected by water soluble ions and molecules involves, not only the net electrical charge, but also a physical property called electrical polarizability. In the lab, we use a method by which electrical polarizability is determined from measurements of index of refraction and mass density as a function of solute concentration. This research will provide understanding in how polarizability of a molecule affects a cellular membrane by observing the zeta potential of a lipid vesicle at varying concentrations of one molecule in solution. The dioleoylphosphatidylserine (DOPS) lipid was utilized, which contains two monounsaturated hydrocarbon chains with eighteen carbons each and a negatively charged head group that consists of both an amine and carboxylic acid. The results showed that while the vesicles maintained approximately a -60 mV charge in water, addition of ions altered the zeta potential in the positive direction as the concentration increased. However, this trend does not immediately appear upon adding ions, instead the charge fluctuates at lower concentrations. The trend has been observed in both divalent chlorides and adenosine triphosphate solutions. Future research will focus on other divalent chlorides—including magnesium, manganese, and cobalt—as well as organic phosphates and phospholipids with different head groups such as dilauroylphosphatidylcholine (DLPC), a neutral lipid. This research will help us to further understand how molecules and ions in the surrounding environments affect cellular membranes in regards to zeta potential, size, and formation of multilamellar vesicles (MLVs). Funding: National Science Foundation Research Experience for Undergraduates (REU) Award #1659688

Keon Jones (Poster #82)
A sensitive electrochemical method to determine lead in water and soil

Lead is one of the most toxic heavy metal in the environment. Its presence is due to human activities notably, lead in gasoline, lead-based paint, lead-containing pesticides, lead in ammunition and sinkers, and incinerator ash or water from lead pipes. Lead poisoning can cause a number of adverse human health effects but it’s particularly detrimental to the neurological development of growing children. Therefore, frequent testing and precise monitoring of Pb in soil and water is important to assess and control lead contamination. We hereby report on developing a stripping voltammetric method using glassy carbon electrodes modified with bismuth nanoparticles (GC-BiNPs) to detect lead in drinking water and soil. Voltammetric stripping measurements have historically utilized mercury in the forms of hanging mercury drop and mercury film electrode to measure heavy metal ions. This is mainly because clean surfaces can be easily be regenerated with a new mercury drop. However, because of mercury toxicity and risks associated with its disposal its use as an electrode material for stripping measurements is severely restricted. We’re utilizing the unique properties of bismuth such as its ability to form alloys with different metals, to develop a sensitive method to detect lead. Preliminary results show that using GC-BiNPs we can detect low levels of lead down to 1 parts per billion in water. The research findings on the stripping voltammetric method development will be presented. Funding: LSAMP; SMART ; IUSB

E-Lexus Thornton (Poster #119)
Modification of the microchannel plate (MCP) detectors in the recoil mass separator St. George

The Recoil Mass Separator St George in Notre Dame’s Nuclear Science Laboratory (NSL) is being used for the study of low level (α,γ) reactions using inverse kinematics to better understand the helium burning processes in a star. ST GEORGE has two MCP detectors that amplify and multiply electrons into electrical pulses that can be seen on an oscilloscope. To make the MCP detectors display a better pulse, and to make the MCP detectors conveniently easy to remove from the mass separator, we decided to modify the makeup of both MCP detectors and add two delay boards and a basic circuit board to both MCP detectors. The Autodesk Inventor software was used for the drawing process and the circuit board was designed by hand. The process and/or results of the modifications and new additions will be described. Funding: NSF Grant PHY-0959816

Friday, October 13, 2017

ChemOffice Professional Comes to IU South Bend

The software suite ChemOffice Profesional is now available to IU South Bend faculty and staff. It can be downloaded and installed on personal computers from IUware. It houses an array of software, but most interesting to students will be the components ChemDraw and Chem3D.

ChemDraw allows users to draw high-quality two-dimensional molecular structures in skeletal form. It can compute simple properties such as molecular mass and elemental composition, but also has a wide range of stored information about existing compounds such as their melting and boiling points. ChemDraw can also determine the IUPAC name of compounds (see below left - please click on photo for higher resolution) and likewise produce the structure given the name. It can even predict NMR spectra for compounds (see below right  - please click on photo for higher resolution), which will surely aid students of organic chemistry to test their ability to interpret and predict NMR spectra.
Chem3D allows a two-dimensional structure from ChemDraw to be visualized and manipulated in three dimensions.  Bond lengths and bond angles are predicted based on average empirical data, but better estimates of these properties and many others can be obtained from built-in molecular modelling capabilities. Chem3D even interfaces with quantum mechanical software to allow Hartree-Fock and density functional calculations. We interfaced with GAMESS to produce the image above of one of two HOMO for benzene. (Paradox = How can you have two HOMOs?)

Tuesday, October 10, 2017

Nanotechnology - Size Matters!

Last week the First Year Seminar students in Dr. Anderson's CHEM-N 190 Nanotechnology: Size Matters class made solar cells from raspberry juice and titanium dioxide on a semiconductive glass surface. This is an example of Dye Sensitized Solar Cells which are at the cutting edge of thin film solar photovoltaic technology. With two-inch square panels, students cranked out a satisfying 0.3 volts per panel (see bottom left picture)!  It helped that the day happened to be mostly sunny. With this experience making solar cells, they should be well-informed for this week's field trip to Inovateus Solar.  Anderson's course is the second course offered at IU South Bend to focus on nanotechnology to support the new nanotechnology tracks offered for certain STEM majors.

Friday, September 8, 2017

Student Spotlight

Michele Costantino is a senior biochemistry major who has returned to school after obtaining a BA in graphic design from our partner campus in Bloomington. Like many of our students, she works part-time, but she does so teaching courses in graphic design as an adjunct instructor at Ivy Tech Community College! Her prior academic experience and maturity has surely given her an advantage in pursuing her second degree, but there can be  no doubt that raw ability is also powering her excellent performance. 
In the spring semester, Costantino earned an honorable mention at the IU South Bend Undergraduate Research Performance for her oral presentation Reversible Self-Assembly Using Protein Conformational Changes on her research last summer with Professor Rizk that was supported by an IU South Bend SMART grant.  Also last spring, she was awarded an honorable mention in the national Barry Goldwater Scholarship Program. She is the second student at IU South Bend to have won such an honor. By the end of the spring semester she had also acquired two more honors: the Bender Scholarship Award and an undergraduate summer research fellowship. The Bender Scholarship Award honors students who have demonstrated multidisciplinary activities, community involvement, and leadership - in addition to high academic performance. Her summer research at IUPUI's Integrated Nanosystems Development Institute (INDI) was sponsored by the National Science Foundation.
At IUPUI, Costantino worked with Dr. Horia Petrache in the biophysics department. Dr. Petrache’s work focuses on the effects of organic molecules on lipid membranes. Over the ten weeks of research, Costantino calculated the polarizability (the susceptibility to change of a molecule's dipole moment) by measuring the density, refractive index, and concentration of analyte solutions. In addition to these calculations, she used dynamic light scattering to measure the size of lipid vesicles and the surface charge of the vesicles in solution. While the program spanned only ten weeks, Costantino’s research was part of a larger project studying the relationship between organic molecules, such as adenosine triphosphate (ATP) and lipid membranes. Dr. Petrache’s lab continues to study these interactions using 2D NMR and x-ray diffraction and plans to present these findings at the 62nd Annual Meeting of the Biophysical Society in San Francisco this February. Outside of her research, Costantino was also able to speak to researchers working the Big G project studying gravity and work with students in the program who intend to patent their work.
This fall, Costantino will apply to graduate schools to study protein engineering. Her summer research will help her stand out from the crowd by showing her ability to work on interdisciplinary projects. In addition, it will further her graduate studies, giving her experience in biophysics that could not otherwise be obtained in a standard undergraduate curriculum. Costantino gained not only experience and education, but she maintains contact with the other REU students and will see them again at this year’s Louis Stokes Midwest Center of Excellence 2017 Annual Conference in October where she will present her summer's work. 
If you are interested in a PAID summer research program like this one please contact a faculty member as soon as possible to identify suitable programs and to prepare a competitive application.

Tuesday, August 29, 2017

Welcome Professor Gopeekrishnan Sreenilayam

Our department gladly welcomes Professor Gopeekrishnan Sreenilayam as a one-year visiting professor to teach our sophomore organic chemistry sequence. He earned his Ph.D. in Organic Chemistry from the University of Iowa in 2011. While Sreenilayam is no greenhorn at teaching, having served as an adjunct lecturer position at the College at Brockport (State University of New York), he brings to us vast research experience from postdoctoral fellowships at both Temple University and the University of Rochester. Sreenilayam’s most recent work investigates an unusual type of organic synthesis where rather than make use of typical organic reagents, he and his colleagues rely on a biochemical approach in which they use the heme center of hemoglobin essentially as a chiral complex ion to catalyze organic reactions to produce chiral products. We have only one concern regarding Sreenilayam: will he be able to refill that bowl of candy on his desk fast enough to accommodate the horde of organic students that will be visiting him? 

Tuesday, August 22, 2017

Solar Eclipse on the First Day of Class

There was a great turnout at IU South Bend for the solar eclipse.  Even though there was only 87% occlusion at South Bend, it was still a memorable sight. Gretchen Anderson's freshman nanotechnology class made pinhole viewers which were quite a popular way to indirectly view the eclipse to avoid eye injuries. But even more impressive were the thousands of pinhole viewers made by light filtering through the trees (bottom left). Even colanders (bottom right) and kitchen strainers were used to view the eclipse. Special thanks to the Physics Club and the Department of Physics and Astronomy for setting up telescopes and to-scale models. And don't worry if you missed the eclipse because you'll get another chance in 2024 which should be even more impressive with almost 97% occlusion!

Saturday, August 19, 2017

Anderson and Feighery take on new roles

While it may seem like there is a power struggle in the department, that couldn't be further from the truth; Professors Anderson and Feighery both personify collegiality and have taken up the role of chair when it was necessary to do so. But now Anderson has once again taken the helm of the ship that is called the Department of Chemistry and Biochemistry - and based on her previous tenure as department chair we know she won't be sitting down on the job.  And to top it off, Anderson will also chair the search committee this fall for our new organic chemist.  On the other hand, Feighery, who was chair, has moved his office from Northside Hall to Weikamp so he can better serve the campus in his new position as Associate Dean of the College of Liberal Arts and Sciences.  Fortunately, Feighery will continue teaching as our department's inorganic chemist.   We wish success for both Anderson and Feighery in their new roles.