Research group
The research in Solomon Tesfalidet Lab is focused on development of electrochemical approaches that can be used in the fields of chemical analysis, material science, and cancer research.
In our research group we work with:
Modification of electrode surfaces using various techniques of chemosorption and electrochemical grafting
Characterization, validation and application of modified electrode surfaces for use as sensors/biosensors
Fabrication of electrocatalytic materials
Sensor development is all about combining the sensitivity of electroanalytical methods with the selectivity of the sensing surface. The chemical component (receptor) in the sensor recognizes an analyte and produces an electrical signal which can be related to the concentration.
Omotayo Adeniyi is a postdoctoral fellow in Solomon Tesfalidet's lab.
ImageKemiska institutionen
Electrochemical sensor surfaces for detection of anticancer drugs
This project deals with development of reliable, quick, and simple quantitative metric for monitoring the level of therapeutic drugs, in patients who are under chemotherapy.
Methotrexate (MTX), 4-amino-N10-methylpteroylglutamic acid, is an anticancer drug used for treatment of different forms of cancer, including lymphoma, sarcoma and leukemia. The effective concentration range of anticancer drug is often limited to a relatively narrow therapeutic window. At low concentrations, the therapeutic activity toward cancer cells is poor while an unacceptable toxicity toward healthy cells is observed at high concentrations. The dosage/level of MTX needs therefore to be regularly controlled and individualized.
Today, the analytical methods used in hospitals are not adequate enough for real time measurement of MTX and there is a need for alternative methods. The group has previously developed a concept for imobilizing MTX antibody on chemically modified electrode surfaces, and used it as biosensor for the detection of MTX in spiked blood samples.
Publications:
1. Mwanza d., Sereilakhena P., Tesfalidet S*, Mashazi P*.: Electrografting of isophthalic acid monolayer and covalent attachment of antibody onto carbon surfaces: construction of capacitive biosensor for methotrexate detection. Electrochim. Acta (2021), 398, 139360
2. Phal S., Shatri B., Berisha A., Geladi P., Lindholm-Sethson B., Tesfalidet S.*: Covalently electrografted carboxyphenyl layers onto gold surface serving as a platform for the construction of an immunosensor for detection of methotrexate. J. Electroanal. Chem (2018), 812, 235-243.
3. Phal S., Lindholm-Sethson., Geladi P., Shchukarev A., Tesfalidet S.:* Determination of methotrexate in Spiked Human Blood Serum using Multifrequency Electrochemical Immittance Spectroscopy and Multivariate Data Analysis, Anal. Chim. Acta (2017), 987, 15-2
4. Tesfalidet S.* Geladi P., Shimizu K., Lindholm-Sethson B.: Detection of methotrexate in a flow system using electrochemical impedkance spectroscopy and multivariate data analysis, Anal. Chim. Acta (2016), 914, 1-6. 10.1016/j.aca.2016.02.012
ImageSolomon Tesfalidet
Electrochemical sensor for field analysis of heavy metals
The concept of the electrode modification, has also been directed to the development of sensors that can be used for field analysis of heavy metals such as lead and cadmium. The ongoing research is focused on investigation of the electrodeposition/reduction step with respect to sensitivity and interference from intermetallic interactions, when several metal ions are deposited at the same time.
Publications:
1. Phal S., Huyền N., Berisha A., Tesfalidet S*: In situ Bi/carboxyphenyl-modified glassy carbon electrode as a sensor platform for detection of Pb2+ and Cd2+ using square wave anodic stripping voltammetry. Sensing and Bio-sensing Research (2021), 34, 100455
Understanding the Surface Chemistry of Modified Electrodes
In a recently initiated project we are working with synthesis, characterization, and application of graphenated-carbon nanotubes (g-CNTs) for electrocatalysis, where we see the possibility of extending the experiences towards: generation of energy and storage; oxygen evolution and reduction reaction (OER, ORR); production of metal-air batteries and supercapacitors.
Publications:
1. Haziri V., Phal S., Boily J-F., Berisha a., Tesfalidet S.: Oxygen interactions with covalently grafted 2D nanometric carboxyphenyl thin films – an experimental and DFT study. Coatings (2022), 12, 1
2. Phal S., Shimizu K., Mwanza D., Mashazi P., Shchukarev A., Tesfalidet S.:*: Electrografting of 4-carboxybenzenediazonium on glassy carbon electrode: the effect of concentration on the formation of mono and multilayers. Molecules (2020), 25, 4575
3. Orqusha N., Phal S., Berisha A., Tesfalidet S.: Experimental and theoretical study of the covalent grafting of triazole layer onto the gold surface. Materials (2020), 13, 2927