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3. State-of-the-Art in Smart Contact Lenses for Human Machine Interaction

Author

Xia, Yuanjie, Khamis, Mohamed, Fernandez, F. Anibal, Heidari, Hadi, Butt, Haider, Ahmed, Zubair, Wilkinson, Tim, and Ghannam, Rami

Subjects
Computer Science - Human-Computer Interaction
Abstract

Contact lenses have traditionally been used for vision correction applications. Recent advances in microelectronics and nanofabrication on flexible substrates have now enabled sensors, circuits and other essential components to be integrated on a small contact lens platform. This has opened up the possibility of using contact lenses for a range of human-machine interaction applications including vision assistance, eye tracking, displays and health care. In this article, we systematically review the range of smart contact lens materials, device architectures and components that facilitate this interaction for different applications. In fact, evidence from our systematic review demonstrates that these lenses can be used to display information, detect eye movements, restore vision and detect certain biomarkers in tear fluid. Consequently, whereas previous state-of the-art reviews in contact lenses focused exclusively on biosensing, our systematic review covers a wider range of smart contact lens applications in HMI. Moreover, we present a new method of classifying the literature on smart contact lenses according to their six constituent building blocks, which are the sensing, energy management, driver electronics, communications, substrate and the interfacing modules. Based on recent developments in each of these categories, we speculate the challenges and opportunities of smart contact lenses for human-machine interaction. Moreover, we propose a novel self-powered smart contact lens concept with integrated energy harvesters, sensors and communication modules to enable autonomous operation. Our review is therefore a critical evaluation of current data and is presented with the aim of guiding researchers to new research directions in smart contact lenses., Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible

Published
2021
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8. A sustainable approach to derive sheep corneal scaffolds from stored slaughterhouse waste

Author

Ali, Zehara M, primary, Wang, Xinyu, additional, Shibru, Meklit G, additional, Alhosani, Maha, additional, Alfadhli, Nouf, additional, Alnuaimi, Aysha, additional, Murtaza, Fiza F, additional, Zaid, Aisha, additional, Khaled, Rodaina, additional, Salih, Ahmed E, additional, Vurivi, Hema, additional, Daoud, Sayel, additional, Butt, Haider, additional, Chan, Vincent, additional, Pantic, Igor V, additional, Paunovic, Jovana, additional, and Corridon, Peter R, additional

Published
2024
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14. Glucose-Sensitive Hydrogel Optical Fibers Functionalized with Phenylboronic Acid.

Author

Yetisen, Ali K, Jiang, Nan, Fallahi, Afsoon, Montelongo, Yunuen, Ruiz-Esparza, Guillermo U, Tamayol, Ali, Zhang, Yu Shrike, Mahmood, Iram, Yang, Su-A, Kim, Ki Su, Butt, Haider, Khademhosseini, Ali, and Yun, Seok-Hyun

Subjects
diagnostics, fiber optics, glucose sensing, hydrogels, light transmission, Physical Sciences, Chemical Sciences, Engineering, Nanoscience & Nanotechnology
Abstract

Hydrogel optical fibers are utilized for continuous glucose sensing in real time. The hydrogel fibers consist of poly(acrylamide-co-poly(ethylene glycol) diacrylate) cores functionalized with phenylboronic acid. The complexation of the phenylboronic acid and cis-diol groups of glucose enables reversible changes of the hydrogel fiber diameter. The analyses of light propagation loss allow for quantitative glucose measurements within the physiological range.

Published
2017

17. Multifunctional and multimaterial contact lenses: tailored solutions for tunable color filtering and tear pH sensing.

Author

Sakr, Abdelrahman, Salih, Ahmed, Hisham, Muhammed, Elsherif, Mohamed, Schiffer, Andreas, and Butt, Haider

Subjects
CONTACT lenses, LIGHT filters, COLOR blindness, COLOR vision, POROUS polymers, LENSES, POLYMERS, FILTERS & filtration
Abstract

Colour vision disorders, pose challenges in perceiving and distinguishing specific colours. To address these challenges, technologies such as colour-filtering glasses and contact lenses have been developed. However, customisation of eyewear for individual patients remains a challenge. This research aims to design multifunctional contact lenses combining colour filtering and pH sensing capabilities for personalised colour vision correction. A pH-responsive, Neutral red dye-doped hydrogel was developed and optimised for the vat photo polymerization-based 3D printing process. A novel in-house multimaterial 3D printing technique was employed for printing lenses exhibiting both colour filtering and pH sensing capabilities. 3D printed samples contained outer radial rings, made from porous and pH-responsive polymer. The optically tunable dye-doped resin was also applied to the central part of the lenses to achieve customised wavelength blockage. The lenses demonstrate potential for customised colour vision correction and pH monitoring of the tear film. [ABSTRACT FROM AUTHOR]

Published
2024
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19. Computational approaches for evaluating morphological changes in the corneal stroma associated with decellularization

Author

Pantic, Igor V., primary, Cumic, Jelena, additional, Valjarevic, Svetlana, additional, Shakeel, Adeeba, additional, Wang, Xinyu, additional, Vurivi, Hema, additional, Daoud, Sayel, additional, Chan, Vincent, additional, Petroianu, Georg A., additional, Shibru, Meklit G., additional, Ali, Zehara M., additional, Nesic, Dejan, additional, Salih, Ahmed E., additional, Butt, Haider, additional, and Corridon, Peter R., additional

Published
2023
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20. Photonic devices based on periodic arrays of carbon nanotubes and silicon nanopillars

Author

Butt, Haider, Wilkinson, Timothy, and Amaratunga, Gehan

Subjects
621.36, Metamaterials, Photonic crystals, Fresnel lenses, Periodic arrays, Carbon nanotubes, Silicon nanopillars
Abstract

This document presents the modelling and characterization of novel photonic devices based on periodic arrays of multiwalled carbon nanotubes. Multiwalled carbon nanotubes are mostly metallic in nature and interesting plasmonic effects are observed when nanotubes are grown close together, with spacing of about 400 nm. The effective electronic mass on the nanotubes changes, due to mutual coupling between them and they start displaying dielectric properties which are inherently different from the their own, forming metamaterials. We present a plasmonic high pass filtering application of carbon nanotube based metamaterials. Some promising modelling and experimental results are demonstrated showing a strong cut-off filtering effect at the plasma frequency displayed by the periodic arrays of multiwalled carbon nanotubes. The artificial negative dielectric constant displayed by the nanotube arrays was also successfully utilised for producing micron-scaled applications like optical waveguides and negative lenses for overcoming the diffraction limit. The fabrication of these optical devices using the arrays of silicon nanopillars was also considered. These arrays when fabricated at nano-scaled dimensions (of about 400 nm) present a greater degree of periodicity and require a simpler fabrication process compared to carbon nanotubes. We report the detailed computational analysis on silicon nanopillars based photonic crystals, waveguides and metamaterials which operate well within in the optical regime. However, due to the fabrication limitations, the fabricated Si nanopillars presented an inverted cone shape profile along their lengths. These inverted nanocone structures were successfully utilised for enhancing reflection from Si surfaces for applications in photovoltaic devices. Lastly we present a novel application of carbon nanotube arrays for producing micron-scale Fresnel lens arrays. Forests of carbon nanotubes were utilised as absorbing media on top of a bare silicon substrate. Optical diffraction of light across the nanotube forests produced strong focusing of light, at focal lengths of order 125 microns. Numerical simulations were in excellent agreement with the measured results.

Published
2012

21. A scalable corneal xenograft platform: simultaneous opportunities for tissue engineering and circular economic sustainability by repurposing slaughterhouse waste

Author

Wang, Xinyu, primary, Shakeel, Adeeba, additional, Salih, Ahmed E., additional, Vurivi, Hema, additional, Daoud, Sayel, additional, Desidery, Luca, additional, Khan, Raheema L., additional, Shibru, Meklit G., additional, Ali, Zehara M., additional, Butt, Haider, additional, Chan, Vincent, additional, and Corridon, Peter R., additional

Published
2023
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27. Photonic hydrogel sensors

Author

Yetisen, Ali K., Butt, Haider, Volpatti, Lisa R., Pavlichenko, Ida, Humar, Matjaž, Kwok, Sheldon J.J., Koo, Heebeom, Kim, Ki Su, Naydenova, Izabela, Khademhosseini, Ali, Hahn, Sei Kwang, and Yun, Seok Hyun

Published
2016
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31. Optical Fiber Sensors: Working Principle, Applications, and Limitations

Author

Elsherif, Mohamed, primary, Salih, Ahmed E., additional, Muñoz, Monserrat Gutiérrez, additional, Alam, Fahad, additional, AlQattan, Bader, additional, Antonysamy, Dennyson Savariraj, additional, Zaki, Mohamed Fawzi, additional, Yetisen, Ali K., additional, Park, Seongjun, additional, Wilkinson, Timothy D., additional, and Butt, Haider, additional

Published
2022
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39. Healthcare Applications of pH-Sensitive Hydrogel-Based Devices: A Review

Author

Hendi, Asail, Umair Hassan, Muhammad, Elsherif, Mohamed, Alqattan, Bader, Park, Seongjun, Yetisen, Ali Kemal, and Butt, Haider

Subjects
biomedical applications, Wound Healing, technology, industry, and agriculture, biocompatible, pH-sensitive, Hydrogels, macromolecular substances, Review, Hydrogen-Ion Concentration, sensors, complex mixtures, Bandages, Drug Liberation, Drug Delivery Systems, Animals, Food Industry, Humans
Abstract

pH-sensitive hydrogels have been developed greatly over the past few years. This has been possible due to the synthesis of new hydrogel systems with increased sensitivity – a sensitivity of up to 10−5 pH units has already been established. Recently, pH-sensitive hydrogels have shown to be very useful in biomedical applications, such as targeted cancer treatment and treatment of skin lesions. Prolonged drug release has been made available through the use of such hydrogels. The synthesis of pH-sensitive hydrogels is also quick and cost-effective. This review presents a background on the properties of pH-sensitive hydrogels and discusses some of the hydrogels with different sensitivity ranges and their possible applications. A range of synthesis processes have also been briefly introduced along with the fabrication of different structures such as microcantilevers and contact lenses.

Published
2020

43. Integration of paper microfluidic sensors into contact lenses for tear fluid analysis

Author

Moreddu, Rosalia, Elsherif, Mohamed, Adams, Hadie, Moschou, Despina, Cordeiro, Maria F., Wolffsohn, James S., Vigolo, Daniele, Butt, Haider, Cooper, Jonathan M., and Yetisen, Ali K.

Abstract

In this article, using the integration of paper microfluidics within laser-inscribed commercial contact lenses, we demonstrate the multiplexed detection of clinically relevant analytes including hydrogen ions, proteins, glucose, nitrites and l-ascorbic acid, all sampled directly from model tears. In vitro measurements involved the optimization of colorimetric assays, with readouts collected, stored and analyzed using a bespoke Tears Diagnostics smartphone application prototype. We demonstrate the potential of the device to perform discrete measurements either for medical diagnosis or disease screening in the clinic or at the point-of-care (PoC), with future applications including monitoring of ocular infections, uveitis, diabetes, keratopathies and assessing oxidative stress.

Published
2020

48. Facet-Time: Using Information Seeking Strategies to Support Exploration of Time Series Data

Author

Butt, Haider Ali, Hoeber, Orland, Hamilton, Howard, Maguire, R. Brien, and Oriet, Christopher

Abstract

A Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Science in Computer Science, University of Regina. xiv, 122 p. The notion of time has important value in people’s lives. By analyzing timeoriented data, we can understand underlying trends in the data. Graphically representing the data is useful for analysis because a single visualization can represent much information. Some tools providing visualizations for time-series data are well supported for lookup tasks; however, their support for exploratory search tasks are minimal. In exploratory search tasks, users may not have a specific search goal or they may have ill-defined information needs. They usually learn by iterating through and interpreting search results and perform investigation over them before integrating the obtained information into their knowledge. In this thesis, an analytical tool (Facet-Time) is proposed that supports users in analyzing temporal data with a specific focus on supporting exploratory search. Facet-Time utilizes information visualization and interactive techniques to help users in finding information they are seeking and satisfying their search goals. It allows users with ambiguous search goals to interactively gain information about the search results. Facet-Time provides information scent support to assist users in choosing their path of exploration while they are defining queries. It also provides the visualization of time-series data where users can analyze the data and also make comparisons of subsets of data. User evaluations were conducted to validate the design variations and features of Facet-Time. The outcome of the evaluations gave mostly mixed results, i.e., some experimental measures have significant value for some variations of Facet- Time and some measures do not have much significance. Improvements were observed in three subjective measures (usefulness, ease of use, and satisfaction) when using the sparklines feature versus when using no sparklines feature. Student yes

Published
2019

49. Carbon Nanotube Array Based Binary Gabor Zone Plate Lenses

Author

Deng, Sunan, Jwad, Tahseen, Li, Chi, Benton, David, Yetisen, Ali K., Jiang, Kyle, Dai, Qing, and Butt, Haider

Subjects
Multidisciplinary Sciences, Science & Technology, genetic structures, FRESNEL, lcsh:R, Science & Technology - Other Topics, lcsh:Medicine, lcsh:Q, DIFFRACTION PATTERNS, lcsh:Science, Article
Abstract

Diffractive zone plates have a wide range of applications from focusing x-ray to extreme UV radiation. The Gabor zone plate, which suppresses the higher-order foci to a pair of conjugate foci, is an attractive alternative to the conventional Fresnel zone plate. In this work, we developed a novel type of Beynon Gabor zone plate based on perfectly absorbing carbon nanotube forest. Lensing performances of 0, 8 and 20 sector Gabor zone plates were experimentally analyzed. Numerical investigations of Beynon Gabor zone plate configurations were in agreement with the experimental results. A high-contrast focal spot having 487 times higher intensity than the average background was obtained.

Published
2017

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