Anas Bsoul received a B.Sc. degree in Computer Engineering from Jordan University of Science and Technology in 2009 and a M.A.Sc. degree in Electrical and Computer Engineering from the University of British Columbia in 2011. Anas is currently a Ph.D. student working on developing a printing technology that can be integrated with common microfluidic, allowing for on-chip microfluids processing followed by their direct printing. We have termed this concept as Lab-on-a-Printer, which as an extension to the well-known concept of Lab-on-a-Chip.
Journal: Lab on a Chip, vol. 16, pp. 3351-3361
Date: July 2016
Abstract: In this paper, we present a disposable inkjet dispenser platform technology and demonstrate the Lab-on-a-Printer concept, an extension of the ubiquitous Lab-on-a-Chip concept, whereby microfluidic modules are directly integrated into the printhead. The concept is demonstrated here through the integration of an inkjet dispenser and a microfluidic mixer enabling control over droplet composition from a single nozzle in real-time during printing. The inkjet dispenser is based on a modular design platform that enables the low-cost microfluidic component and the more expensive actuation unit to be easily separated, allowing for the optional disposal of the former and reuse of the latter. To limit satellite droplet formation, a hydrophobic-coated and tapered micronozzle was microfabricated and integrated with the fluidics to realize the dispenser. The microfabricated devices generated droplets with diameters ranging from 150–220 μm, depending mainly on the orifice diameter, with printing rates up to 8000 droplets per second. The inkjet dispenser is capable of dispensing materials with a viscosity up to ∼19 mPa s. As a demonstration of the inkjet dispenser function and application, we have printed type I collagen seeded with human liver carcinoma cells (cell line HepG2), to form patterned biological structures.
Journal: Chemical Communications, vol. 52, pp. 7810-7813
Date: May 2016
Abstract: Mesoporous resins with chiral nematic order were used as scaffolds to construct novel iridescent metal–polymer composites. Gold, silver and palladium nanoparticles were formed by an in situ reduction reaction. We have investigated the effects of concentration and time on the deposition. As a proof-of-concept, we demonstrate that this process can be extended to patterning photonic resins by inkjet printing.
Conference Proceedings: The 17th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2015)
Date: October 2015
Abstract: This work introduces and demonstrates the concept of Lab-on-a-Printer whereby microfluidiccomponents are integrated with inkjet dispensers. This concept allows for multi-functional microfluidic materials processing to be performed on chip and direct post-process printing of those materials enabling printing of programmable gradients and more generally structures with programmable composition. This concept is demonstrated with a disposable PDMS device that integrates an inkjet dispenser technology with a microfluidic mixer.
Journal: Angewandte Chemie-International Edition, vol. 54(14), pp. 4304–4308
Date: January 2015
Abstract: Chiral nematic mesoporous phenol-formaldehyde resins, which were prepared using cellulose nanocrystals as a template, can be used as a substrate to produce latent photonic images. These resins undergo swelling, which changes their reflected color. By writing on the films with chemical inks, the density of methylol groups in the resin changes, subsequently affecting their degree of swelling and, consequently, their color. Writing on the films gives latent images that are revealed only upon swelling of the films. Using inkjet printing, it is possible to make higher resolution photonic patterns both as text and images that can be visualized by swelling and erased by drying. This novel approach to printing photonic patterns in resin films may be applied to anti-counterfeit tags, signage, and decorative applications.
Conference Proceedings: The 17th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2013 – Oral 8.7%)
Date: October, 2013
Abstract: This paper reports on the design, fabrication and demonstration of a polydimethylsiloxane (PDMS)/SU-8 inkjet dispenser with the following novel features: (1) the use of low-cost fabrication process and bio-compatible materials, (2) the use of hydrophobic SU-8 micro-nozzles to limit satellite droplet formation, (3) a modular device design that allows for the reuse of the external actuator, (4) the capability of printing hydrogel constructs, (5) a limited cross-contamination risk as the device is disposable, (6) and the potential for integration with other PDMS microfluidic systems. The device successfully dispenses droplets with diameters ranging from 80-130µm at rates of 2-1000 droplets/second.
Conference Proceedings: The 17th International Conference on Solid-State Sensors, Actuators and Microsystems (Traducers 2013)
Date: June 2013
Abstract: This paper describes a novel method of fabricating three dimensional (3D) hydrogel structures primarily for use in tissue engineering. A microfluidic chip capable of coaxial flow focusing is fabricated to crosslink a solution of the hydrogel sodium alginate using a calcium chloride sheath fluid. The sodium alginate rapidly gels and is dispensed from the chip as a fibre. The chip is synchronized with a 3D positioning system to deposit the fibres in a controlled pattern and stack them to form 3D constructs. Furthermore, a 3D printing process is used to fabricate the coaxial flow focusing microfluidic chips, providing a simple means of producing cylindrical channel geometries.
Journal: IEEE/ASME Journal of Microelectromechanical Systems
Date: April 2013
Abstract: This paper reports a bulk-micromachined shape-memory-alloy (SMA) actuator in the form of a spiral coil that constitutes an inductor-capacitor resonant circuit. The out-of-plane actuation of the SMA spiral-coil inductor is wirelessly controlled using external radio frequency (RF) magnetic fields. The resonant circuit is used as a frequency-selective wireless heater in which the SMA inductor produces heat to activate its own actuation when resonated with the RF magnetic field. The direct integration of bulk-micromachined nitinol SMA with a threshold temperature of 65 °C into a planar microfabrication process is enabled to build the 3-D spiral-coil SMA actuator in a self-assembled manner using a SiO2 reset layer patterned on the SMA coil. The fabricated SMA structure yields an out-of-plane displacement of 466 μm in the cold state. The full actuation to the flat state is reached at 70°C upon tuning the field frequency to ~ 230 MHz with an RF output power of 0.7 W. The developed actuator is demonstrated to provide a maximum force of 30 mN. The temporal response of the actuator is revealed to be two to three times faster than that of previously reported wireless SMA actuators with separate heat sources.
Journal: Applied Physics Letters
Date: May 2012
Abstract: We present a strain gauge that uses a carbon nanotube (CNT) forest, partially embedded in a Parylene-C membrane, as a piezoresistor. The device exhibits high sensitivity with a gauge factor of 4.52 or higher for strains up to ∼1.5%, offering much higher sensitivity in the strain range than those reported for other types of CNT-forest/polymer composite piezoresistors. The gauge also shows a linear response to bending strains generated by forces applied perpendicularly to the membrane with a 55-ppm/mN sensitivity. These findings suggest promising characteristics for a variety of sensing applications of the CNT-forest/Parylene film.
Conference Proceedings: 25th IEEE Int’l Conf. Micro Electro Mechanical Systems (MEMS 2012)
Date: January, 2012
Abstract: This work investigates reverse-polarity dry micro-electro-discharge machining (μEDM) of pure carbon-nanotube (CNT) forests that are used as cathodes in the process, as opposed to conventional μEDM where the material to be machined forms the anode. The new configuration with the reversed polarity is observed to generate higher discharge currents, most likely due to effective field-emission from CNTs. This effect allows the process to be performed at very low discharge energies, ~80× smaller than in the conventional normal-polarity case, with the machining voltage and tolerance down to 10 V and 2.5 μm, respectively, enabling high-precision high-aspect-ratio micropatterning in the forests.
Journal: Journal of Applied Physics
Date: October, 2011
Abstract: This work investigates dry micro-electro-discharge machining (μEDM) of vertically aligned carbon nanotube (CNT) forests that are used as cathodes in the process, as opposed to conventional μEDM where the material to be machined forms the anode, toward achieving higher precision in the patterned microstructures. The new configuration with the reversed polarity is observed to generate higher discharge currents in the process, presumably due to effective field-emission from CNTs. This effect allows the process to be performed at very low discharge energies, approximately 80× smaller than in the conventional normal-polarity case, with the machining voltage and tolerance down to 10 V and 2.5 μm, respectively, enabling high-precision high-aspect-ratio micropatterning in the forests. The new approach is also demonstrated to make the process faster, cleaner, and more stable than conventional processing. Spectroscopic analyses of the forests processed by reverse μEDM show no evidence of significant crystalline deterioration or contamination in the CNTs.
Journal: IET Electronics Letters
Date: July, 2011
Abstract: A pressure sensor functionalizedwith vertically aligned carbon nanotubes is presented. The sensor is fabricated to have a multi-walled carbon-nanotube forest supported by a deflectable 8 µm-thick Parylene-C membrane that is suspended by the silicon frame. The responses of the fabricated sensors are experimentally characterised. The sensitivities to positive and negative gauge pressures are found to be comparable in magnitude with the average values of -986 and +816 ppm/kPa, respectively. The measurement also reveals that the temperature coefficient of resistance for the forest suspended with the Parylene membrane is -515 ppm/°C and ~3× smaller than that for the forest fixed onto the silicon substrate.
Articles in News:
Journal: IET Electronics Letters
Date: July, 2011
Abstract: A carbon nanotube (CNT) forest-based pressure sensor that has a nearly symmetrical response for both positive and negative gauge pressures has been unveiled. Researchers at the University of British Columbia (UBC) in Canada created the sensor using a suspended diaphragm entirely covered with a CNT forest as a piezoresistive sensing element. Such a sensor could be used in a wide range of fields, and it is of particular interest for medical applications as the device is coated in Parylene, a biocompatible polymer.