Bulgarian Academy of Sciences
Institute of Optical Materials and Technologies
"Acad. Jordan Malinowski"
Bulgarian Academy of Sciences
Institute of Optical Materials and Technologies
"Acad. Jordan Malinowski"
"Acad. Jordan Malinowski"
Acad. J. Malinowski (1923 - 1996)
Academician Jordan Malinowski was born on 03.06.1923 ...
Invitation
National projects
National Science Infrastructure
INFRAMAT
National Science Infrastructure
INFRAMAT
INFRAMAT
Most significant scientific achievement for 2024
Thin ZnO films deposited by electro-spray method for QCM ammonia sensing, coordinator Prof. Dr. Tsvetanka Babeva
The electrospray deposition conditions of ZnO films have been optimized in order functionalization of QCM sensors for ammonia detection to be performed. A sensor sensitivity of 0.12 Hz/ppm was achieved with a layer thickness of only 200 nm. The substrate...
Most significant scientific achievement for 2024
Thin ZnO films deposited by electro-spray method for QCM ammonia sensing, coordinator Prof. Dr. Tsvetanka Babeva
Electrospray deposition of ZnO thin films (a), SEM pictures of ZnO surface morphology (b) and normalized data for rms roughness, photoluminescence, water contact angle and sensor sensitivity (c).The electrospray deposition conditions of ZnO films have been optimized in order functionalization of QCM sensors for ammonia detection to be performed. A sensor sensitivity of 0.12 Hz/ppm was achieved with a layer thickness of only 200 nm. The substrate temperature (150, 170, and 200°C), emitter voltage (15 and 18 kV), and precursor feed rate (10 and 15 μL/min) were varied. Films deposited at a substrate temperature of 150°C, a voltage of 18 kV and a feed rate of 10 μl/min exhibit the highest sensitivity. It was demonstrated that for achieving the highest sensitivity thin films should satisfy simultaneously all the three criteria: i) high roughness, indicating a highly developed surface, ii) strong photoluminescence in the visible range, which is associated with defects in the lattice and iii) small water contact angle that means hydrophilic surface.
Considering the chemical and mechanical stability of the layers deposited by the electrospray method, as well as their low cost, the obtained results open new possibilities for the application of electrospray ZnO layers in gas and biosensors.
The results were published in open access paper (Marinov, G., Alexieva, G., Lazarova, K., Gergova, R., Ivanov, P., Babeva, T. (2024). Optimization of Electrospray Deposition Conditions of ZnO Thin Films for Ammonia Sensing, Nanomaterials, 14(12)) and were included in PhD thesis of Dr. Georgi Marinov, defended in July 2024.
Most significant scientific achievement for 2024
Thin ZnO films deposited by electro-spray method for QCM ammonia sensing, coordinator Prof. Dr. Tsvetanka Babeva
Electrospray deposition of ZnO thin films (a), SEM pictures of ZnO surface morphology (b) and normalized data for rms roughness, photoluminescence, water contact angle and sensor sensitivity (c).
The electrospray deposition conditions of ZnO films have been optimized in order functionalization of QCM sensors for ammonia detection to be performed. A sensor sensitivity of 0.12 Hz/ppm was achieved with a layer thickness of only 200 nm. The substrate temperature (150, 170, and 200°C), emitter voltage (15 and 18 kV), and precursor feed rate (10 and 15 μL/min) were varied. Films deposited at a substrate temperature of 150°C, a voltage of 18 kV and a feed rate of 10 μl/min exhibit the highest sensitivity. It was demonstrated that for achieving the highest sensitivity thin films should satisfy simultaneously all the three criteria: i) high roughness, indicating a highly developed surface, ii) strong photoluminescence in the visible range, which is associated with defects in the lattice and iii) small water contact angle that means hydrophilic surface.Considering the chemical and mechanical stability of the layers deposited by the electrospray method, as well as their low cost, the obtained results open new possibilities for the application of electrospray ZnO layers in gas and biosensors.
The results were published in open access paper (Marinov, G., Alexieva, G., Lazarova, K., Gergova, R., Ivanov, P., Babeva, T. (2024). Optimization of Electrospray Deposition Conditions of ZnO Thin Films for Ammonia Sensing, Nanomaterials, 14(12)) and were included in PhD thesis of Dr. Georgi Marinov, defended in July 2024.
Most significant applied scientific achievement for 2024
Detection of Helicobacter pylori in saliva based on Surface Plasmon Resonance by binding of Lewisb (Leb) blood group antigen to specific adhesin BabA, coordinator Georgi Dyankov
Helicobacter pylori affects about half of the population around the world. Therefore, timely and reliable diagnosis of the disease...
Most significant applied scientific achievement for 2024
Detection of Helicobacter pylori in saliva based on Surface Plasmon Resonance by binding of Lewisb (Leb) blood group antigen to specific adhesin BabA, coordinator Georgi Dyankov
AFM micrograph of the Le b film deposited on a gilded diffraction grating (A); Resonance displacement as a function of H. pylori concentrations in biochips incubated with contaminated filtered (0.2 µm) and non-filtered saliva (B). AFM images of an SPR biochip with attached H. Pylori in its coccoid form (C).Helicobacter pylori affects about half of the population around the world. Therefore, timely and reliable diagnosis of the disease is required. Non-invasive detection of H. pylori is the technique of choice for infection control. Although the bacteria load in human saliva is low, obtaining samples from saliva is simple and convenient, as compared to obtaining stomach, blood and stool samples. Hence, a detection method of high specificity and sensitivity is required. The purpose of this article is to evaluate the applicability of the Surface Plasmon Resonance (SPR) biosensor, based on the binding of Lewisb (Leb) blood group antigen to the specific adhesin BabA, for H.pylori detection in saliva. Our studies on saliva, artificially contaminated with H. pylori, demonstrated the high specificity of the BabA - Leb binding reaction. The results obtained indicated that there are two mechanisms that inhibit the viability of H. pylori. The first involves the direct interaction between H. pylori and the oral antagonistic bacteria, and the second involves the bactericidal effect of certain proteins produced by the oral background bacterial flora. Although the sensitivity of detection of the proposed method needs to be increased, the results obtained proved its applicability and feasibility for H. pylori detection in saliva and the good prospects it offers for both clinical application and as a rapid point-of-care test.
The research was financially supported by the Bulgarian National Science Fund, project №KP-06-N78/9. Results related to the achievement have been published in the following articles: Dyankov, G., Genova-Kalou, P., Najdenski, H., Kassovski, V., Mankov, V., Kisov, H., Hikova, E., Strijkova, V., Veselinov, P., Malinowski, N.. Detection of Helicobacter pylori in saliva based on surface plasmon resonance by binding of Lewis b (Leb) blood group antigen to specific adhesin BabA, Biotechnology and Biotechnological Equipment, 38, 1, 2024, 2379828, DOI:10.1080/13102818.2024.; Dyankov, G., Najdenski, H., Kasovski, V., Zaharieva, M., Kisov, H., Hikova, E., Dimitrova, T., Malinowski, N. Is Reliable Helicobacter Pylori Detection in Saliva Possible? AIP Conference Proceedings, 2924, 2024, 020001, DOI:10.1063/5.0183331.
Most significant applied scientific achievement for 2024
Detection of Helicobacter pylori in saliva based on Surface Plasmon Resonance by binding of Lewisb (Leb) blood group antigen to specific adhesin BabA, coordinator Georgi Dyankov
AFM micrograph of the Le b film deposited on a gilded diffraction grating (A); Resonance displacement as a function of H. pylori concentrations in biochips incubated with contaminated filtered (0.2 µm) and non-filtered saliva (B). AFM images of an SPR biochip with attached H. Pylori in its coccoid form (C).
Helicobacter pylori affects about half of the population around the world. Therefore, timely and reliable diagnosis of the disease is required. Non-invasive detection of H. pylori is the technique of choice for infection control. Although the bacteria load in human saliva is low, obtaining samples from saliva is simple and convenient, as compared to obtaining stomach, blood and stool samples. Hence, a detection method of high specificity and sensitivity is required. The purpose of this article is to evaluate the applicability of the Surface Plasmon Resonance (SPR) biosensor, based on the binding of Lewisb (Leb) blood group antigen to the specific adhesin BabA, for H.pylori detection in saliva. Our studies on saliva, artificially contaminated with H. pylori, demonstrated the high specificity of the BabA - Leb binding reaction. The results obtained indicated that there are two mechanisms that inhibit the viability of H. pylori. The first involves the direct interaction between H. pylori and the oral antagonistic bacteria, and the second involves the bactericidal effect of certain proteins produced by the oral background bacterial flora. Although the sensitivity of detection of the proposed method needs to be increased, the results obtained proved its applicability and feasibility for H. pylori detection in saliva and the good prospects it offers for both clinical application and as a rapid point-of-care test. The research was financially supported by the Bulgarian National Science Fund, project №KP-06-N78/9. Results related to the achievement have been published in the following articles: Dyankov, G., Genova-Kalou, P., Najdenski, H., Kassovski, V., Mankov, V., Kisov, H., Hikova, E., Strijkova, V., Veselinov, P., Malinowski, N.. Detection of Helicobacter pylori in saliva based on surface plasmon resonance by binding of Lewis b (Leb) blood group antigen to specific adhesin BabA, Biotechnology and Biotechnological Equipment, 38, 1, 2024, 2379828, DOI:10.1080/13102818.2024.; Dyankov, G., Najdenski, H., Kasovski, V., Zaharieva, M., Kisov, H., Hikova, E., Dimitrova, T., Malinowski, N. Is Reliable Helicobacter Pylori Detection in Saliva Possible? AIP Conference Proceedings, 2924, 2024, 020001, DOI:10.1063/5.0183331.