Papers by Jasen Devasagayam
Scientific reports, Mar 18, 2024
Research Square (Research Square), Oct 5, 2023
IEEE Access
This work introduces a sensor for dairy antibiotic detection of ciprofloxacin in milk. We provide... more This work introduces a sensor for dairy antibiotic detection of ciprofloxacin in milk. We provide an important tool for antibiotic detection in milk and the main contributions of this work are as follows. We introduce a technique based on florescence spectroscopy and lock-in amplification for sensing ciprofloxacin in milk that is capable of detection below the regulatory limit. We compare the system against one without the integrated lock-in amplification, as in traditional fluorescence sensors. We provide microchip capillary electrophoresis results and place our work in context for future integration with microchip capillary electrophoresis.
University of Guelph, Apr 1, 2021
Scientific Reports, 2020
Detecting antibiotics in the milk supply chain is crucial to protect humans from allergic reactio... more Detecting antibiotics in the milk supply chain is crucial to protect humans from allergic reactions, as well as preventing the build-up of antibiotic resistance. The dairy industry has controls in place at processing facilities, but controls on dairy farms are limited to manual devices. Errors in the use of these manual devices can result in severe financial harm to the farms. This illustrates an urgent need for automated methods of detecting antibiotics on a dairy farm, to prevent the shipment of milk containing antibiotics. This work introduces the microchip capillary electrophoresis dairy device, a low-cost system that utilizes microchip capillary electrophoresis as well as fluorescence spectroscopy for the detection of ciprofloxacin contained in milk. The microchip capillary electrophoresis dairy device is operated under antibiotic-absent conditions, with ciprofloxacin not present in a milk sample, and antibiotic-present conditions, with ciprofloxacin present in a milk sample. T...
IEEE Transactions on Instrumentation and Measurement, 2018
Hyperspectral imaging (HSI) is an emergent instrumentation technology with great potential in man... more Hyperspectral imaging (HSI) is an emergent instrumentation technology with great potential in many applications, due to its ability to measure important spectral features. However, the widespread adoption of HSI requires the development of accessible (i.e., inexpensive and uncomplicated) HSI instrumentation architectures. In this paper, we present, design, develop, and evaluate an accessible HSI instrumentation architecture, with snapshot operation, based on the integration of readily available components and frequency multiplexing with Fourier analyses. In the experimental work, an incident image beam is divided into spatial image channels, each with an assigned dynamic binary code via a dynamic coded aperture. This dynamic coded aperture is constructed from repurposed diffractive optical disc technologies and is patterned with strategic opaque and transparent regions. When it is rotated by a motor, dynamic binary codes are used, along with Fourier analyses, to identify the diffraction of each spatial image channel. The spatially overlapped spectra from the diffraction are directed onto a charge-coupled device sensor, and each spatial image channel is distinguished through Fourier analyses. The resulting Fourier amplitude spectra are transformed into corresponding functions of wavelength, and this transformation is based on the experimental instrumentation geometry. The performance of the HSI instrumentation architecture is evaluated using a comparison with data from a commercial spectrometer. The presented HSI instrumentation architecture can be adapted for 2-D operation. Ultimately, the presented HSI instrumentation architecture can benefit regions of the world that have limited financial resources and a need for accessible HSI technologies.
ELECTROPHORESIS, 2022
Investigating microfluidic flow profiles is of interest in the microfluidics field for the determ... more Investigating microfluidic flow profiles is of interest in the microfluidics field for the determination of various characteristics of a lab‐on‐a‐chip system. Microparticle tracking velocimetry uses computational methods upon recording video footage of microfluidic flow to ultimately visualize motion within a microfluidic system across all frames of a video. Current methods are computationally expensive or require extensive instrumentation. A computational method suited to microparticle tracking applications is the robust Kanade–Lucas–Tomasi (KLT) feature‐tracking algorithm. This work explores a microparticle tracking velocimetry program using the KLT feature‐tracking algorithm. The developed program is demonstrated using pressure‐driven and EOF and compared with the respective mathematical fluid flow models. An electrostatics analysis of EOF conditions is performed in the development of the mathematical using a Poisson's Equation solver. This analysis is used to quantify the zeta potential of the electroosmotic system. Overall, the KLT feature‐tracking algorithm presented in this work proved to be highly reliable and computationally efficient for investigations of pressure‐driven and EOF in a microfluidic system.
Photonic Instrumentation Engineering VII
Hyperspectral imaging (HSI) technology has become prominent, with a wide range of applications: f... more Hyperspectral imaging (HSI) technology has become prominent, with a wide range of applications: food quality control, crop monitoring, and medical diagnostics. As HSI is able to capture spatial and spectral data, it is highly desirable, but highly complex. However, this functionality presents a challenge for data acquisition as three-dimensional HSI images must be acquired by an image sensor of one less dimension. Thus, HSI systems are often pushbroom systems, with twodimensional images being successively constructed over time from line scans. Additionally, HSI is expensive and difficult to operate. A snapshot HSI system is developed to address these challenges, whereby the additional image dimension is encoded onto an occupied dimension on the image sensor. Additionally, the snapshot HSI system is constructed from low cost, readily available components. The presented snapshot HSI system consists of a transparent diffraction optical disc bonded to an aperture mask, with alternating transparent and opaque regions, acting as an optical chopper when rotated by a DC brushless motor. This allows separation of the spectra of overlapped pixels on the HSI image sensor. When an incident beam passes through this optical chopper, many frequencies (corresponding to spatial channels) are imposed by the binary mask, while undergoing diffraction across the visible spectrum. Overlapped spectra are directed at a charge coupled device, where Fourier analyses distinguish each spatial channel. System geometry is used to transform the Fourier amplitude spectra into functions of wavelength for each spatial pixel. The design is experimentally validated through comparison to a commercially available spectrometer.
When producing milk in the dairy industry, reliable quality assurance systems need to be in place... more When producing milk in the dairy industry, reliable quality assurance systems need to be in place in order to detect allergens which can potentially harm humans upon consumption. Milk can very often be contaminated with hazardous antibiotics used by farmers to treat cows. Current quality assurance biosensors are manual methods and prone to lots of human error. Failure during this process can be financially harmful to dairy companies, and potentially harmful to human health. This shows a necessity for an automated biosensor to detect antibiotics in milk before shipment. This work presents an automated biosensor based on microchip electrophoresis and fluorescence spectroscopy to detect ciprofloxacin in milk, which is a commonly used antibiotic to help treat mastitis of cows. The design and testing results of the low-cost system are presented in this paper. In order to detect the presence of the antibiotic, the milk sample needs to be separated into its constituents. This is achieved b...
This paper presents an inexpensive and easy‐to‐implement voltage sequencer instrument for use in ... more This paper presents an inexpensive and easy‐to‐implement voltage sequencer instrument for use in microchip capillary electrophoresis (MCE) actuation. The voltage sequencer instrument takes a 0–5 V input signal from a microcontroller and produces a reciprocally proportional voltage signal with the capability to achieve the voltages required for MCE actuation. The unit developed in this work features four independent voltage channels, measures 105 × 143 × 45 mm (width × length × height), and the cost to assemble is under 60 USD. The system is controlled by a peripheral interface controller and commands are given via universal serial bus connection to a personal computer running a command line graphical user interface. The performance of the voltage sequencer is demonstrated by its integration with a fluorescence spectroscopy MCE sensor using pinched sample injection and electrophoretic separation to detect ciprofloxacin in samples of milk. This application is chosen as it is particula...
ABSTRACTMagnetoencephalography (MEG) has been revolutionised in recent years by optically pumped ... more ABSTRACTMagnetoencephalography (MEG) has been revolutionised in recent years by optically pumped magnetometers (OPMs). “OPM-MEG” offers higher sensitivity, better spatial resolution and lower cost than conventional instrumentation based on superconducting quantum interference devices (SQUIDS). Moreover, OPMs offer the possibility of motion robustness and lifespan compliance, dramatically expanding the range of MEG applications. However, OPM-MEG remains nascent technology; it places stringent requirements on magnetic shielding, and whilst a number of viable systems exist, most are custom made and there have been no cross-site investigations showing the reliability of data. In this paper, we undertake the first cross-site OPM-MEG comparison, using near identical commercial systems scanning the same participant. The two sites are deliberately contrasting, with different magnetic environments: a “green field” campus university site with an OPM-optimised shielded room (low interference) ...
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Papers by Jasen Devasagayam