The connection of macrosystems with microsystems for in-line measurements is important in differe... more The connection of macrosystems with microsystems for in-line measurements is important in different biotechnological processes as it enables precise and accurate monitoring of process parameters at a small scale, which can provide valuable insights into the process, and ultimately lead to improved process control and optimization. Additionally, it allows continuous monitoring without the need for manual sampling and analysis, leading to more efficient and cost-effective production. In this paper, a 3D printed microfluidic (MF) chip for glucose (Glc) sensing in a liquid analyte is proposed. The chip made in Poly(methyl methacrylate) (PMMA) contains integrated serpentine-based micromixers realized via stereolithography with a slot for USB-like integration of commercial DropSens electrodes. After adjusting the sample’s pH in the first micromixer, small volumes of the sample and enzyme are mixed in the second micromixer and lead to a sensing chamber where the Glc concentration is measur...
Gold electrodes are one of most prevalent substrates in electrochemical biosensors because they c... more Gold electrodes are one of most prevalent substrates in electrochemical biosensors because they can be easily and highly efficiently functionalized with thiolated biomolecules. However, conventional methods to fabricate gold electrodes are costly, time consuming and require onerous equipment. Here, an affordable method for rapid fabrication of an electrochemical immune-sensor forEscherichia colidetection is presented. The gold electrode was generated using 24-karat gold leaves and low-cost polyvinyl chloride adhesive sheets covered with an insulating PTFE layer. The gold-leaf electrode (GLE) was patterned using laser ablation and characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electronic microscopy, contact angle and 3D profiling. The GLEs were modified by a self-assembled mercaptopropionic monolayer, followed by surface activation to allow binding of the specific anti-E. coliantibody via carbodiimide linking. The biosensor showed a detection li...
IEEE EUROCON 2019 -18th International Conference on Smart Technologies
In this paper, we propose a novel planar passive micro-mixer realized using sets of parallelogram... more In this paper, we propose a novel planar passive micro-mixer realized using sets of parallelogram barriers. The influence of different mixer geometrical parameters to the mixing efficiency have been analyzed using Comsol Multiphysics® simulation tools. Characteristics of the proposed mixer have been optimized for the different flow rates in the micro-channels in order to obtain small variation of the fluid concentration at the output of the mixer. Proposed mixer presents a universal planar solution that can be easily realized using different fabrication technology such as 3D printing, xurographic technique, PDMS, or combination of different hybrid microfluidic technologies.
Zenodo (CERN European Organization for Nuclear Research), Dec 1, 2021
AIM: Sensors incorporated in lab-on-a-chip (LOC) platforms permit in situ measurements of analyte... more AIM: Sensors incorporated in lab-on-a-chip (LOC) platforms permit in situ measurements of analytes over time [1]. LOC approach with integrated impedimetric sensor has been used in this study aiming to develop a sensor for biomass estimation during cell cultivation in the novel, cost-effective microbioreactor (MBR). Interaction between cells and electromagnetic radiation in different frequency ranges enables detection and characterization of various cellular parameters. In the radio-frequency (RF) range, viable cells are polarizable and act as dipoles, hence the number of cells directly influences the dielectric permittivity of measured impedance [2]. In that sense, an impedimetric approach allows sensing the cell concentration and therefore biomass. Additionally, the LOC approach enables good control and collection of data relevant for the cultivation process [3]. METHODS: Cost-effective technologies of MBR and sensor fabrication are presented, as well as their integration and testing results obtained with MRC-5 cells used as model adherent cells. RESULTS: Developed impedimetric sensor in MBR has been able to detect number of cells i.e. biomass, as well as all the phases in batch cell cultivation over 96 h - lag, exponential, stationary, and death phase. CONCLUSION: By combining biocompatible and transparent materials, the LOC system provides a basis that allows additional integration of electrodes, sensors, or optical components, and has a potential for the rapid production of low-cost and reliable MBRs that can be used in cultured meat research. Impedance-based sensing is a good approach for biomass monitoring in MBRs.
2017 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS), 2017
In this paper, we propose a novel 0 dB forward-wave coupler realized in microstrip-ridge gap wave... more In this paper, we propose a novel 0 dB forward-wave coupler realized in microstrip-ridge gap waveguide technology. The coupler is based on two microstrip-ridges coupled through an array of mushroom inclusions. A detailed design procedure is presented including the design of the hosting PMC structure, microstrip-ridge and the coupler. The proposed structure represents the first forward-wave coupler realized in gap waveguide technology. It is characterized by high coupling level of 0.3 dB at 13.54 GHz, and the 0.48 dB coupling variance over the bandwidth of 26%. Also, good performances in terms of the isolation and directivity have been achieved.
Abstract We study a waveguide structure supporting acoustic spoof plasmon polaritons (aSSPPs) per... more Abstract We study a waveguide structure supporting acoustic spoof plasmon polaritons (aSSPPs) perturbed by a defect, whose specifically tailored geometry enables controllable transmission characterized by a uniform phase distribution and very steep narrowband response. The structure is analyzed using transmission-line theory and numerical simulations, providing evidence for its use in advanced filters, isolators and sensor technology. In order to demonstrate the applicability of the aSSPP waveguide with defect, two selective narrowband filter designs are discussed and explored. Furthermore, we propose an acoustic isolator that exploits steady fluid flow to break reciprocity and provide large isolation in a narrowband region. We also propose a sensor for liquid analytes, in which the grooves of the aSSPP waveguide serve as microfluidic channels, while the sensing principle is based on the spectral shift of the transmission peak for different mixtures of water and glycerol. The sensor shows a good sensitivity and fast response, with a potential for further development for applications in water quality monitoring.
In this paper, we propose a novel microwave microfluidic sensor with dual-sensing capability. The... more In this paper, we propose a novel microwave microfluidic sensor with dual-sensing capability. The sensor is based on a dual-mode resonator that consists of a folded microstrip line loaded with interdigital lines and a stub at the plane of symmetry. Due to the specific configuration, the resonator exhibits two entirely independent resonant modes, which allows simultaneous sensing of two fluids using a resonance shift method. The sensor is designed in a multilayer configuration with the proposed resonator and two separated microfluidic channels—one intertwined with the interdigital lines and the other positioned below the stub. The circuit has been fabricated using low-temperature co-fired ceramics technology and its performance was verified through the measurement of its responses for different fluids in the microfluidic channels. The results confirm the dual-sensing capability with zero mutual influence as well as good overall performance. Besides an excellent potential for dual-sen...
Page 1. Novel Left-Handed Unit Cell for Multi-Band Filtering Applications Vasa Radonić#1, Vesna C... more Page 1. Novel Left-Handed Unit Cell for Multi-Band Filtering Applications Vasa Radonić#1, Vesna Crnojević-Bengin#1, Branka Jokanović*2 #Dept. of Electronics, Faculty of Technical Sciences, University of Novi Sad, Serbia ...
The cationic content of water represents a major quality control parameter that needs to be follo... more The cationic content of water represents a major quality control parameter that needs to be followed by a rapid, on-site, and low-cost method. Herein, we report a novel method for a facile monitoring of the mineral content of drinking water by making use of responsive complex emulsions. The morphology of biphasic oil-in-water droplets solely depends on the balance of interfacial tensions, and we demonstrate that changes in the surfactant effectiveness, caused by variations in the mineral content inside the continuous phase, can be visualized by monitoring internal droplet shapes. An addition of metal cations can significantly influence the surfactant critical micelle concentrations and the surface excess values and therefore induce changes in the effectiveness of ionic surfactants, such as sodium dodecyl sulfate. The morphological response of Janus emulsions droplets was tracked via a simple microscopic setup. We observed that the extent of the droplet response was dependent on the salt concentration and valency, with divalent cations (responsive for water hardness), resulting in a more pronounced response. In this way, Ca2+ and Mg2+ levels could be quantitatively measured, which we showcased by determination of the mineral content of commercial water samples. The herein demonstrated device concept may provide a new alternative rapid monitoring of water hardness levels in a simple and cost-effective setup.
We tested the efficacy of PreSens SensorPlugs for monitoring bacterial cultures in microfluidic b... more We tested the efficacy of PreSens SensorPlugs for monitoring bacterial cultures in microfluidic bioreactors (MBs), which is important in the context of monitoring potential contamination in the culture meat bioprocess. Escherichia coli (ATCC® 25922™) was cultivated inside a custom-made MB with integrated SensorPlugs. The optical measurements showed the characteristic course of E. coli growth, and allowed precise assessment of current culture status at all times.
With an increasing interest of the agricultural community in precision agriculture, this paper ai... more With an increasing interest of the agricultural community in precision agriculture, this paper aims to compare two novel sensing approaches for crop monitoring. The recently developed multispectral proximal sensor named Plant-O-Meter and Sentinel-2 satellite, which carries a multispectral optical instrument, are two sensors suitable for agricultural applications. Each of them has pros and cons regarding spatial, spectral and temporal resolutions and their complementary use will surely bring added value compared to information retrieved by a single sensor. In order to correctly address the problem of data fusion, compatibility studies between the two sensors are necessary. In this study, a maize field was sensed on several dates in 2018 growing season using both sensors. Numerous vegetation indices based on different spectral channel combinations were calculated and the results were compared using linear regression analysis. First results showed good positive correlations between the...
2017 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS), 2017
In this paper, we demonstrate the influence of the line-to-spacing ratio of the Hilbert fractal a... more In this paper, we demonstrate the influence of the line-to-spacing ratio of the Hilbert fractal antenna to its radiation characteristic. The proposed antennas realized using Hilbert fractal curves of the third order have been designed to operate at 2.45 GHz according IEEE 802.15.1 standard. Due to specific configuration of the Hilbert fractal curves and mutual coupling between fractal segments, the radiation patterns of the proposed antenna can be significantly changed by changing the line-to-spacing ratio of the Hilbert fractal radiators. The proposed antenna has been fabricated in Low Temperature Co-fired Ceramic (LTCC) technology. The measured result of the Hilbert dipole antenna confirmed its good impedance matching and return loss.
In this paper, a microwave microfluidic sensor based on spoof surface plasmon polaritons (SSPPs) ... more In this paper, a microwave microfluidic sensor based on spoof surface plasmon polaritons (SSPPs) was proposed for ultrasensitive detection of dielectric constant. A novel unit cell for the SSPP structure is proposed and its behaviour and sensing potential analysed in detail. Based on the proposed cell, the SSPP microwave structure with a microfluidic reservoir is designed as a multilayer configuration to serve as a sensing platform for liquid analytes. The sensor is realized using a combination of rapid, cost-effective technologies of xurography, laser micromachining, and cold lamination bonding, and its potential is validated in the experiments with edible oil samples. The results demonstrate high sensitivity (850 MHz/epsilon unit) and excellent linearity (R2 = 0.9802) of the sensor, which, together with its low-cost and simple fabrication, make the proposed sensor an excellent candidate for the detection of small changes in the dielectric constant of edible oils and other liquid a...
In this work, a very compact dual-band filter based on folded quarter-wavelength resonators is pr... more In this work, a very compact dual-band filter based on folded quarter-wavelength resonators is proposed. Specific configuration of the filter results in four independently controlled transmission zeros which provide very high selectivity of the passbands. The proposed configuration is analysed in detail and a design procedure is presented. To demonstrate the feasibility of the proposed approach, two dual-band filters operating at WLAN frequencies of 2.4/3.5 GHz and 3.5/5.25 GHz are designed, fabricated and measured. To the best of the authors' knowledge, proposed 2.4/3.5 GHz dual-band filter is the most compact solution presented so far that at the same time exhibits high-selectivity and low losses.
The connection of macrosystems with microsystems for in-line measurements is important in differe... more The connection of macrosystems with microsystems for in-line measurements is important in different biotechnological processes as it enables precise and accurate monitoring of process parameters at a small scale, which can provide valuable insights into the process, and ultimately lead to improved process control and optimization. Additionally, it allows continuous monitoring without the need for manual sampling and analysis, leading to more efficient and cost-effective production. In this paper, a 3D printed microfluidic (MF) chip for glucose (Glc) sensing in a liquid analyte is proposed. The chip made in Poly(methyl methacrylate) (PMMA) contains integrated serpentine-based micromixers realized via stereolithography with a slot for USB-like integration of commercial DropSens electrodes. After adjusting the sample’s pH in the first micromixer, small volumes of the sample and enzyme are mixed in the second micromixer and lead to a sensing chamber where the Glc concentration is measur...
Gold electrodes are one of most prevalent substrates in electrochemical biosensors because they c... more Gold electrodes are one of most prevalent substrates in electrochemical biosensors because they can be easily and highly efficiently functionalized with thiolated biomolecules. However, conventional methods to fabricate gold electrodes are costly, time consuming and require onerous equipment. Here, an affordable method for rapid fabrication of an electrochemical immune-sensor forEscherichia colidetection is presented. The gold electrode was generated using 24-karat gold leaves and low-cost polyvinyl chloride adhesive sheets covered with an insulating PTFE layer. The gold-leaf electrode (GLE) was patterned using laser ablation and characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electronic microscopy, contact angle and 3D profiling. The GLEs were modified by a self-assembled mercaptopropionic monolayer, followed by surface activation to allow binding of the specific anti-E. coliantibody via carbodiimide linking. The biosensor showed a detection li...
IEEE EUROCON 2019 -18th International Conference on Smart Technologies
In this paper, we propose a novel planar passive micro-mixer realized using sets of parallelogram... more In this paper, we propose a novel planar passive micro-mixer realized using sets of parallelogram barriers. The influence of different mixer geometrical parameters to the mixing efficiency have been analyzed using Comsol Multiphysics® simulation tools. Characteristics of the proposed mixer have been optimized for the different flow rates in the micro-channels in order to obtain small variation of the fluid concentration at the output of the mixer. Proposed mixer presents a universal planar solution that can be easily realized using different fabrication technology such as 3D printing, xurographic technique, PDMS, or combination of different hybrid microfluidic technologies.
Zenodo (CERN European Organization for Nuclear Research), Dec 1, 2021
AIM: Sensors incorporated in lab-on-a-chip (LOC) platforms permit in situ measurements of analyte... more AIM: Sensors incorporated in lab-on-a-chip (LOC) platforms permit in situ measurements of analytes over time [1]. LOC approach with integrated impedimetric sensor has been used in this study aiming to develop a sensor for biomass estimation during cell cultivation in the novel, cost-effective microbioreactor (MBR). Interaction between cells and electromagnetic radiation in different frequency ranges enables detection and characterization of various cellular parameters. In the radio-frequency (RF) range, viable cells are polarizable and act as dipoles, hence the number of cells directly influences the dielectric permittivity of measured impedance [2]. In that sense, an impedimetric approach allows sensing the cell concentration and therefore biomass. Additionally, the LOC approach enables good control and collection of data relevant for the cultivation process [3]. METHODS: Cost-effective technologies of MBR and sensor fabrication are presented, as well as their integration and testing results obtained with MRC-5 cells used as model adherent cells. RESULTS: Developed impedimetric sensor in MBR has been able to detect number of cells i.e. biomass, as well as all the phases in batch cell cultivation over 96 h - lag, exponential, stationary, and death phase. CONCLUSION: By combining biocompatible and transparent materials, the LOC system provides a basis that allows additional integration of electrodes, sensors, or optical components, and has a potential for the rapid production of low-cost and reliable MBRs that can be used in cultured meat research. Impedance-based sensing is a good approach for biomass monitoring in MBRs.
2017 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS), 2017
In this paper, we propose a novel 0 dB forward-wave coupler realized in microstrip-ridge gap wave... more In this paper, we propose a novel 0 dB forward-wave coupler realized in microstrip-ridge gap waveguide technology. The coupler is based on two microstrip-ridges coupled through an array of mushroom inclusions. A detailed design procedure is presented including the design of the hosting PMC structure, microstrip-ridge and the coupler. The proposed structure represents the first forward-wave coupler realized in gap waveguide technology. It is characterized by high coupling level of 0.3 dB at 13.54 GHz, and the 0.48 dB coupling variance over the bandwidth of 26%. Also, good performances in terms of the isolation and directivity have been achieved.
Abstract We study a waveguide structure supporting acoustic spoof plasmon polaritons (aSSPPs) per... more Abstract We study a waveguide structure supporting acoustic spoof plasmon polaritons (aSSPPs) perturbed by a defect, whose specifically tailored geometry enables controllable transmission characterized by a uniform phase distribution and very steep narrowband response. The structure is analyzed using transmission-line theory and numerical simulations, providing evidence for its use in advanced filters, isolators and sensor technology. In order to demonstrate the applicability of the aSSPP waveguide with defect, two selective narrowband filter designs are discussed and explored. Furthermore, we propose an acoustic isolator that exploits steady fluid flow to break reciprocity and provide large isolation in a narrowband region. We also propose a sensor for liquid analytes, in which the grooves of the aSSPP waveguide serve as microfluidic channels, while the sensing principle is based on the spectral shift of the transmission peak for different mixtures of water and glycerol. The sensor shows a good sensitivity and fast response, with a potential for further development for applications in water quality monitoring.
In this paper, we propose a novel microwave microfluidic sensor with dual-sensing capability. The... more In this paper, we propose a novel microwave microfluidic sensor with dual-sensing capability. The sensor is based on a dual-mode resonator that consists of a folded microstrip line loaded with interdigital lines and a stub at the plane of symmetry. Due to the specific configuration, the resonator exhibits two entirely independent resonant modes, which allows simultaneous sensing of two fluids using a resonance shift method. The sensor is designed in a multilayer configuration with the proposed resonator and two separated microfluidic channels—one intertwined with the interdigital lines and the other positioned below the stub. The circuit has been fabricated using low-temperature co-fired ceramics technology and its performance was verified through the measurement of its responses for different fluids in the microfluidic channels. The results confirm the dual-sensing capability with zero mutual influence as well as good overall performance. Besides an excellent potential for dual-sen...
Page 1. Novel Left-Handed Unit Cell for Multi-Band Filtering Applications Vasa Radonić#1, Vesna C... more Page 1. Novel Left-Handed Unit Cell for Multi-Band Filtering Applications Vasa Radonić#1, Vesna Crnojević-Bengin#1, Branka Jokanović*2 #Dept. of Electronics, Faculty of Technical Sciences, University of Novi Sad, Serbia ...
The cationic content of water represents a major quality control parameter that needs to be follo... more The cationic content of water represents a major quality control parameter that needs to be followed by a rapid, on-site, and low-cost method. Herein, we report a novel method for a facile monitoring of the mineral content of drinking water by making use of responsive complex emulsions. The morphology of biphasic oil-in-water droplets solely depends on the balance of interfacial tensions, and we demonstrate that changes in the surfactant effectiveness, caused by variations in the mineral content inside the continuous phase, can be visualized by monitoring internal droplet shapes. An addition of metal cations can significantly influence the surfactant critical micelle concentrations and the surface excess values and therefore induce changes in the effectiveness of ionic surfactants, such as sodium dodecyl sulfate. The morphological response of Janus emulsions droplets was tracked via a simple microscopic setup. We observed that the extent of the droplet response was dependent on the salt concentration and valency, with divalent cations (responsive for water hardness), resulting in a more pronounced response. In this way, Ca2+ and Mg2+ levels could be quantitatively measured, which we showcased by determination of the mineral content of commercial water samples. The herein demonstrated device concept may provide a new alternative rapid monitoring of water hardness levels in a simple and cost-effective setup.
We tested the efficacy of PreSens SensorPlugs for monitoring bacterial cultures in microfluidic b... more We tested the efficacy of PreSens SensorPlugs for monitoring bacterial cultures in microfluidic bioreactors (MBs), which is important in the context of monitoring potential contamination in the culture meat bioprocess. Escherichia coli (ATCC® 25922™) was cultivated inside a custom-made MB with integrated SensorPlugs. The optical measurements showed the characteristic course of E. coli growth, and allowed precise assessment of current culture status at all times.
With an increasing interest of the agricultural community in precision agriculture, this paper ai... more With an increasing interest of the agricultural community in precision agriculture, this paper aims to compare two novel sensing approaches for crop monitoring. The recently developed multispectral proximal sensor named Plant-O-Meter and Sentinel-2 satellite, which carries a multispectral optical instrument, are two sensors suitable for agricultural applications. Each of them has pros and cons regarding spatial, spectral and temporal resolutions and their complementary use will surely bring added value compared to information retrieved by a single sensor. In order to correctly address the problem of data fusion, compatibility studies between the two sensors are necessary. In this study, a maize field was sensed on several dates in 2018 growing season using both sensors. Numerous vegetation indices based on different spectral channel combinations were calculated and the results were compared using linear regression analysis. First results showed good positive correlations between the...
2017 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS), 2017
In this paper, we demonstrate the influence of the line-to-spacing ratio of the Hilbert fractal a... more In this paper, we demonstrate the influence of the line-to-spacing ratio of the Hilbert fractal antenna to its radiation characteristic. The proposed antennas realized using Hilbert fractal curves of the third order have been designed to operate at 2.45 GHz according IEEE 802.15.1 standard. Due to specific configuration of the Hilbert fractal curves and mutual coupling between fractal segments, the radiation patterns of the proposed antenna can be significantly changed by changing the line-to-spacing ratio of the Hilbert fractal radiators. The proposed antenna has been fabricated in Low Temperature Co-fired Ceramic (LTCC) technology. The measured result of the Hilbert dipole antenna confirmed its good impedance matching and return loss.
In this paper, a microwave microfluidic sensor based on spoof surface plasmon polaritons (SSPPs) ... more In this paper, a microwave microfluidic sensor based on spoof surface plasmon polaritons (SSPPs) was proposed for ultrasensitive detection of dielectric constant. A novel unit cell for the SSPP structure is proposed and its behaviour and sensing potential analysed in detail. Based on the proposed cell, the SSPP microwave structure with a microfluidic reservoir is designed as a multilayer configuration to serve as a sensing platform for liquid analytes. The sensor is realized using a combination of rapid, cost-effective technologies of xurography, laser micromachining, and cold lamination bonding, and its potential is validated in the experiments with edible oil samples. The results demonstrate high sensitivity (850 MHz/epsilon unit) and excellent linearity (R2 = 0.9802) of the sensor, which, together with its low-cost and simple fabrication, make the proposed sensor an excellent candidate for the detection of small changes in the dielectric constant of edible oils and other liquid a...
In this work, a very compact dual-band filter based on folded quarter-wavelength resonators is pr... more In this work, a very compact dual-band filter based on folded quarter-wavelength resonators is proposed. Specific configuration of the filter results in four independently controlled transmission zeros which provide very high selectivity of the passbands. The proposed configuration is analysed in detail and a design procedure is presented. To demonstrate the feasibility of the proposed approach, two dual-band filters operating at WLAN frequencies of 2.4/3.5 GHz and 3.5/5.25 GHz are designed, fabricated and measured. To the best of the authors' knowledge, proposed 2.4/3.5 GHz dual-band filter is the most compact solution presented so far that at the same time exhibits high-selectivity and low losses.
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