Results

General Scientific Activities

A scientific study was performed, entitled: “Study on the state of the art on spintronic sensors and their integration with microfluidics for Lab-on-a-chip (LOC) applications”. This study focused on the following general aspects:

• Applying positive and negative magnetophoresis in microfluidic systems for manipulating, concentrating and separating magnetically marked biological structures of interest.

• Recent progress regarding detection of magnetic nanoparticles (MNPs) utilized as markers for biological structures.

• New tendencies regarding the use of the Planar Hall effect (PHE) for the detection of MNPs.

Entitled “Microfabrication experiments and characterization of spintronic structures and microfluidic test devices” included:

• Activities dedicated to advanced modelling of spintronic sensors with the purpose of establishing the optimal detection method.

• Activities dedicated to the layout design for the spintronic sensors adapted for magnetic nanoparticles detection.

• Desinging the layout of the microfluidic system.

• Microfabrication experiments of the microfluidic channels for the integrated sensors.

• Deposition and electrical characterization of the spintronic structures.

• Performing magnetic nanoparticles (MNPs) detection tests with spintronic structures.

The magnetic nanoparticles detection experiments utilizing Planar Hall effect (PHE) square sensors, like the ones used in simulations, showed a sensitivity up to 482 mV/emu for a detection surface of about 8 mm². Also, microfabrication experiments of microfluidic systems were performed utilizing PDMS or using standard photolithography on a silicon substrate. The results of these activities were disseminated through scientific articles and communications at specialty conferences.

Published articles

E. Chiriac, B. Adiaconiță, C. Pachiu, M. Avram and C. Bălan, "MicroPIV on carbonic materials embedded in a microfluidic device," 2021 International Semiconductor Conference (CAS), 2021, pp. 169-172,doi: 10.1109/CAS52836.2021.9604134. https://ieeexplore.ieee.org/document/9604134/authors

E. Chiriac, A. M. Bran, C. Voitincu and C. Balan, "Experimental Validation of VOF Method in Microchannel Flows," 2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2021, pp. 1-4, doi: 10.1109/ATEE52255.2021.9425121. https://ieeexplore.ieee.org/document/9425121
E. Chiriac, M. Avram and C. Balan, "Transition from Threads to Droplets in a Microchannel for Liquids with No Viscosity Contrast," 2021 10th International Conference on ENERGY and ENVIRONMENT (CIEM), 2021, pp. 1-4, doi: 10.1109/CIEM52821.2021.9614936. https://ieeexplore.ieee.org/document/9614936

Papers presented at scientific conferences

E. Chiriac, A. M. Bran, C. Voitincu and C. Balan, "Experimental Validation of VOF Method in Microchannel Flows”, The 12th International Symposium on ADVANCED TOPICS IN ELECTRICAL ENGINEERING (ATEE 2021), MARCH 25-27, 2021, Bucharest, Romania, Secțiunea Multiphysics (MPHYS), Thursday, 25 March 2021
E. Chiriac, B. Adiaconiță, C. Pachiu, M. Avram and C. Bălan, "MicroPIV on carbonic materials embedded in a microfluidic device”, 44^th International Semiconductor Conference CAS 2021, October 6 – 8, 2021, Secțiunea MICROSENSORS & MODELLING – Student Papers (Lectures), Wednesday, October 6, 2021, Technical Program, page 4
E. Chiriac, M. Avram, C. Balan, “Transition from Threads to Droplets in a Microchannel for Liquids with No Viscosity Contrast”, 10th International Conference on ENERGY and ENVIRONMENT (CIEM), Bucharest, 14-15 October 2021, SECTION 4 - Fluid Mechanics and Technical Applications, Thursday 14 October 2021, Final Program, Page 20. http://ciem.energ.pub.ro/downloads.html

C. Mușuroi, E. Helerea, M. Volmer, ”A Review on using Magnetoresistive Biosensors for Magnetic Nanoparticles Detection”, 17th MIKLÓS IVÁNYI INTERNATIONAL PHD & DLA SYMPOSIUM, UNIVERSITY OF PÉCS, Hungary, Sectiunea Information Technology 3, cod articol P-123, 25 Oct. 2020, prezentare orală. https://phdsymp.mik.pte.hu/program https://phdsymp.mik.pte.hu/publication - Book of abstracts

M. Volmer, A. Bezergheanu, L. Prejbeanu, C. Mușuroi and M. Oproiu, EXCHANGE BIASED STRUCTURES USED FOR MAGNETIC NANOPARTICLES DETECTION, TIM 20-21 Physics Conference, November 11th - 13th 2021, Timisoara, Romania, Secțiunea Applied Physics and Interdisciplinarity (API), Invited (API-103), Friday 12th of November 2021, Final Program, Page 6, https://timconference.uvt.ro/API_submissions.php

Entitled “Building the demonstrator integrated in the microfluidic system and testing in laboratory conditions” included:

• Microfabrication experiments of the demonstrator chip with spintronic sensors and magnetic biasing system;

• Activities related to the synthesis and functionalization of magnetic nanoparticles utilized for on chip detection;

• Prototyping and fabrication of the microfluidic platform which contains the spintronic chip;

• Functional characterization experiments and validating the microfluidic platform in laboratory conditions for low fields detection of magnetic nanoparticles functionalized with biomolecules of interest.

These activities were built onto results and studies performed into previous stages. Of particular noteworth is that very good results were obtained for the sysnthesis of magnetic nanoparticles through electrochemical methods. Also the demonstrator chip, with microfluidic chambers placed above the spintronic sensors, exhibited sensitivities higher than 0.075 mV/μg of maghemite magnetic nanoparticles functionalized with polyethylene glycol (PEG).

The results of these activities were disseminated through publication of scientific articles and communications in specialty conferences as well as patenting of original results.

Published articles - ISI indexed articles

[1]. B. Tincu, M. Avram, A. Avram, V. Tucureanu, G. Mihai, M. Popa, P. Osiceanu, I. Demetrescu, M. Enachescu, Investigation of plasma-assisted functionalization of pristine single layer graphene, Chemical Physics Letters, Volume 789, 2022, https://doi.org/10.1016/j.cplett.2021.139330.

[2]. T. A. Burinaru, B. Adiaconiţă, M. Avram, P. Preda, A. M. Enciu, E. Chiriac, C. Mărculescu, T. Constantin, M. Militaru, Electrochemical impedance spectroscopy based microfluidic biosensor for the detection of circulating tumor cells, Materials Today Communications, Volume 32, 2022, https://doi.org/10.1016/j.mtcomm.2022.104016.

[3]. Chiriac, E.; Avram, M.; Balan, C., “Investigation of Multiphase Flow in a Trifurcation, Microchannel— A Benchmark Problem”, Micromachines 2022, 13, 974. https://doi.org/10.3390/mi13060974.

[4]. Chiriac, Eugen, Avram, Marioara, and Balan, Corneliu, “Experimental and numerical investigation of hysteresis in multiphase flow in a microchannel.” U.P.B. Sci. Bull., Series A, 84(3), (2022), 191-200.

[5]. C. Mușuroi, M. Volmer, M. Oproiu, J. Neamtu, E. Helerea, Designing a Spintronic based Magnetoresistive Sensor for Current Measurement and Low Field Sensing, articol trimis la Electronics, ISSN 2079-9292, Special issue Advanced Magnetic and Electrical Characterization Techniques,in process of publication

Communications at technical-scientific conferences

[1]. C. Mărculescu, B. Tincu, T. Burinaru, P. Preda, E. Chiriac, A. Matei, M. Avram, “Substrate influence on carbon based bioprinted sensors”, 19th International Conference on Nanoscience & Nanotechnologies (NN22), 5-8 July 2022, Thessaloniki, Grece, Poster prezentation.

[2]. C. Mușuroi, M. Volmer, E. Helerea, M. Oproiu, An analytical approach for magnetoresistive sensor performance on magnetic nanoparticles detection for biosensing systems, International Conference on Analytical and Nanoanalytical Methods for Biomedical and Environmental Sciences (IC-ANMBES 2022), 08 - 10 Iunie, 2022, Brasov, Romania, Secțiunea ”Interfaces and biosensing”, Book of Abstracts, ISSN 2360-3461, pag. 65, https://icanmbes.unitbv.ro/Astracts%20Book_2022_10_iun.pdf, Poster prezentation P.2.5.

[3]. M. Volmer, L. Prejbeanu, A. Bezergheanu, C. Mușuroi, M Oproiu, Micromagnetic Simulations and Experimental Results on Magnetic Nanoparticles Detection with Exchange Biased Structures, The XIII European Magnetic Sensors and Actuators Conference (EMSA 2022), Madrid, 5-8 Iulie 2022, Sectiunea ”MAGNETORESISTANCE, SPIN-VALVES AND MAGNETIC TUNNEL JUNCTIONS” Abstract Book, pag. 80, https://www.emsa2022.com/images/site/Abstracts-Book-EMSA-2022.pdf, Poster prezentation (P-19).

[4]. M. Volmer, M Oproiu, C. Mușuroi, Magnetic Nanoparticles Detection with GMR Sensors by Analyzing their Static and Dynamic Output Signals, The XIII European Magnetic Sensors and Actuators Conference (EMSA 2022), Madrid, 5-8 Iulie 2022, Sectiunea ”MAGNETORESISTANCE, SPIN-VALVES AND MAGNETIC TUNNEL JUNCTIONS”, Abstract Book, pag. 81, https://www.emsa2022.com/images/site/Abstracts-Book-EMSA-2022.pdf, Poster prezentation(P-20).

Patent request

[1]. - Marioara Avram, Bianca-Catalina Tincu (Adiaconita), Andrei Marius Avram, Petruta Preda, Eugen Chiriac, Tiberiu Alecu Burinaru, Catalin Valentin Mărculescu, “Tranzistor cu efect de câmp pe bază de grafit nanocristalin pentru detecția celulelor tumorale circulante”, Patent request, A/00025/2022.

This project had an interdisciplinary character, involving studies in the field of microfluidics, spintronic magnetic sensors,    advanced numerical modelling and microfabrication techniques. The results from all of these activities were used in obtaining the demonstrator sensor. Some representative images from demonstrator development stages are shown bellow:

Picture1en