I have completed the results of our research on fluoroquinolone antibiotics towards the end of the semester of Spring 2015. In addition to the first batch of Raman analysis we have using the 485 nm laser line, we also have obtained another set of data using the 795 nm laser line. We have rerun the sample to validate our initial data and found the peaks to be consistent. As of now, I am starting to finalize the peak assignment together with two junior members of the group for the four fluoroquinolone samples namely norfloxacin, ciprofloxacin, sarafloxacin, and enrofloxacin. We are using the software Gaussian to aid us in peak assignment. I am also doing literature search using Web of Science to start to write a manuscript for possible submission to a peer-reviewed journal. My mentor gave me an outline to follow and we hope to have our first draft by the end of the month. In addition to this, a poster from this study was presented by a junior member that I mentored (Ashley Kuptsow) at the Dyson Society of Fellows Annual Meeting and William Paterson University Undergraduate Research Symposium (WPU-URS) At the WPU-URS , Ashley won as best poster in the field of computational chemistry. I have a very nice experience with this endeavor. I didn’t only learn how to use several instruments but I was also able to mentor two students. Mentoring allow me to learn the materials in-depth since I have to explain to them the principles on how instruments work. This experience enhanced my knowledge and helped me prepare for my graduate study (PhD Chemistry at University at Michigan) this coming fall. I am very thankful to the organizers and most of all to my mentor, Dr. Elmer-Rico E. Mojica for the opportunities given to me.
Spring 2015 semester has provided a wide variety of data and results within the research of fluoroquinolone antibiotics. The antibacterials that we worked on presently in the lab are norfloxacin, ciprofloxacin, sarafloxacin, and enrofloxacin. The results provided within the lab have gotten better since fall 2014. We found peak markers that represent certain samples and can characterize based on these peaks. Initially the peaks gave us trouble due to the signal to noise ratio in the ATR-FTIR since then we modified the initial set up of number of scans and other parameters within the instrument itself. These results will be presented in poster form by one of the students I mentored Ashley in the upcoming Dyson Society of Fellows. In addition, another student who I also mentored, Lexi, will also present a poster on sulfa drugs. Lastly, I will be presenting my study on click chemistry in the same said meeting.
I also have the opportunity to present in the Best Practices Conference last February 27. In this presentation, I shared my research and mentoring experiences with Dr. Mojica. For the remaining of the semester, I was tasked to work on the portable Raman spectrometer with the objective of utilizing them for the analysis of the fluoroquinolone and sulfa drugs. We are also going to validate our preliminary results and write a paper for publication if the results are good.
For the past fall 2014 semester, I have been continuously working on various fluoroquinolone antibiotics, namely ciprofloxacin (CIPRO), norfloxacin (NFX), enrofloxacin (EFX), and sarafloxacin (SFX). We have finished the first trials of analysis using infrared (IR) spectrometer. We encountered difficulties regarding detection of these fluoroquinolone antibiotics many times because of the IR spectrometer itself. When analysis of the sample takes place, the noise within the analysis graph cannot be determined, meaning we cannot get a solid peak of where certain functional groups are within the sample. As we decrease the resolution to be less, we encounter less and less noise and can determine from the data what we have in the sample. However, with lower detection, there is less possibility for specifying and determining different peaks because the detector cannot isolate the noise, so the samples analyzed have to be redone multiple times to get true estimate of the peaks and see if the data is consistent over a period of time.
Again we will have to retest the fluoroquinolone antibiotics samples with the newly attained Raman spectrometer provided by Dr. Mojica and see if there are significant differences between the IR and the Raman data. As stated in my last report, there have been notable finds within the data such as carboxyl groups within the 1700 cm-1 range. There was a notable peak within the 3000-3200 cm-1 which is the alcohol peak that was present in all the samples. To confirm that specific range, we have to check the samples again with the IR and Raman to see if the specific peak is present within given samples. As time progresses on with research and more complications occur with the data, I still learn more and more about the instruments that I am using. Being able to troubleshoot many problems with the instruments which is one of the necessities to know when using an instrument.
Helping fellow junior researchers Ashley Kuptsow and Alexis Javornickhave provided them with knowledge to do independent research within the lab. As I help them with techniques and methods crucial to the research lab, they understand many of concepts of being an independent researcher. They now know how to analyze certain aspects of data given to them and have the ability to work by themselves in the lab. In coming spring 2015 semester will be a crucial time for research. We hope as a result of our research we can find and develop certain methods of determination of the fluoroquinolone with their complex matrices.
I am currently performing vibrational spectroscopy on various samples using IR spectroscopy. The samples I have been analyzing are fluoroquinolone antibiotics namely ciprofloxacin (CIPRO), norfloxacin (NFX), enrofloxacin (EFX), and Sarafloxacin (SFX). Each antibiotic has unique features due to the functional group that are present. For instance, ciprofloxacin which contain a carboxyl group have a unique peak not found in other samples. In addition, a peak at 3000-3200 cm-1 region was found to be presentanol at all samples. This could be possibly due to the OH that are present in the samples of from the ethanol that we used to clean the set-up. We are trying to optimize the method to minimize problems like the one that was mentioned.
In addition, the major problem that I encountered is the detection limit for the IR spectrometer. Since the resolution of the peaks is not clear, we have to re-run samples using different resolutions to find a usable setting to which we can gather better data. The data for the other samples of CIPRO, NFX, EFX, and SFX have to be run again so we can get better resolution of the peaks without all of the noise. On the side notes, I have been helping fellow junior researchers Ashley Kuptsow and Alexis Javornick with their research. I provided them with the necessary tools to do certain aspects of their research. Such methods are analyzing their given samples using the IR spectrometer and processing their data using IGOR software to plot their peaks and see where the transitions and important peaks are found.
Hello, my name is Maximillian Baria, better known as Max. I am a senior at Pace, majoring in Chemistry. I have started my research this fall with Prof. Elmer-Rico Mojica on the project title “Vibrational spectroscopic analysis of antibiotics”. We are studying and analyzing antibiotics using vibrational spectroscopy (Raman and ATR-FTIR). Antibiotics have been in use since the early 20th century. It is used primarily for prevention and treatment of bacterial infections in both human beings and animals. In addition, they are also used as growth promoters in animal industry. Because of the prevalent use of antibiotics, new methods have to be develop to determine their presence. I would like to use vibrational spectroscopy to develop a method in determining and differentiating antibiotics. These methods (Raman and ATR-FTIR) are non-destructive where samples analyzed can be recovered.
The materials and equipment that will be used in my research was already purchased. I have yet to initiate the experiment because of the literary research that I am presently doing on my topic. Since the study of antibiotics has been going on for a long time, I have to take into consideration other perspectives of my research. Throughout this research we want to determine the characteristics from our selected samples. With vibrational spectroscopy we can determine functional groups present within sample and further deduce the differences with each antibiotic. With the portable Raman spectrometer that Dr. Mojica purchased for use by the department, I will try to develop a method to determine antibiotics and compared it with results obtained from lab bench Raman spectrometer. I am going to be assisted by two Forensic Science students who I will be training under my wing. I really like to thank Dr. Mojica for all the opportunities he gave me since starting working on his group three semesters ago. I can never get the REU internship form University of Michigan without his help. I also like to thank Pace University for the grant given to me which I will be using in continuing the research on “click chemistry” that I have done last summer at University of Michigan. I intend to do this research on click chemistry simultaneously with this project.