يوسف عطيه سعود القرشي

 


      
 
الاسم الاول: 
يوسف
اسم العائلة: 
القرشي
الدرجة العلمية: 
دكتوراة
مجال الدراسة: 
هندسة
المؤسسة التعليمية: 
University of Birmingham

 

 

مجال التميز

تميز دراسي و بحثي

 

 

البحوث المنشورة

 

البحث (1):

 

عنوان البحث:

Optical Glucose Sensors Based On Hexagonally-Packed 2.5-Dimensional Photonic Concavities Imprinted In Phenylboronic Acid Functionalized Hydrogel Films

رابط إلى البحث:

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تاريخ النشر:

23/11/2017

موجز عن البحث:

Continuous glucose monitoring aims to achieve accurate control of blood glucose concentration to prevent hypo/hyperglycaemia in diabetic patients. Hydrogel-based systems have emerged as a reusable sensing platform to quantify biomarkers in high-risk patients at clinical and point-of-care settings. The capability to integrate hydrogel-based systems with optical transducers will provide quantitative and colorimetric measurements via spectrophotometric analyses of biomarkers. Here, we created an imprinting method to rapidly produce 2.5D photonic concavities in phenylboronic acid functionalized hydrogel films. Our method exploited diffraction properties of hexagonally-packed 2.5D photonic microscale concavities having a lattice spacing of 3.3 μm. Illumination of the 2.5D hexagonally-packed structure with a monochromatic light source in transmission mode allowed reversible and quantitative measurements of variation in the glucose concentration based on first order lattice interspace tracking. Reversible covalent phenylboronic acid coupling with cis-diols of glucose molecules expanded the hydrogel matrix by 2% and 34% in the presence of glucose concentrations of 1 mM and 200 mM, respectively. A Donnan osmotic pressure induced volumetric expansion of the hydrogel matrix due to increasing glucose concentrations (1–200 mM), resulted in a nanoscale modulation of the lattice interspace, and shifted the diffraction angle (45° to 36°) as well as the interspacing between the 1st order diffraction spots (8 to 3 mm). The sensor exhibited a maximum lattice spacing diffraction shift within a response time of 15 min in a reversible manner. The developed 2.5D photonic sensors may have application in medical point-of-care diagnostics, implantable chips, and wearable continuous glucose monitoring devices.

 

 

 

البحث (2): 

 

عنوان البحث:

LaserInduced Surface Modification Of Contact Lenses 

رابط إلى البحث:

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تاريخ النشر:

26/02/2018

موجز عن البحث:

The authors report on the laserinduced modification of surface properties of contact lenses. Selective areas of the surface of commercial siliconhydrogel contact lenses are patterned in array formats using different powers of the CO2 laser. 1D arrays of different groove densities, channels, and 2D intersecting architecture are fabricated. Contact angle measurements are carried out to measure the surface hydrophilicity, and extent of hydration is linked with the surface profile properties and the space gap between the fabricated patterns, which are controlled by the beam exposure time, beam power, and scan speed. Laser treatment of contact lenses results in improved hydration proportional to the density of laser ablated segments on the surface. The hydration time of water droplets on different lens surfaces is also recorded – all 2D patterned lenses show faster hydration as water quickly diffused into the bulk of the lens due to the extended interfacial area between the contact lens and the water droplet as a consequence of larger areal modification in 2D as compared with 1D patterns. The best wettability properties are obtained with 0.3 mm space gap, 9 W power, and 200 mm s−1 scan speed. Optical microscopy is used to image the 3D surface profiles of the modified lenses and the depth of the patterns and is correlated with the experimental observations. The maximum depth of 40 µm is observed with 0.3 mm space gap, 9 W, and 200 mm s−1 scan speed. Optical transmittance of broadband white light is measured to assess the surface treatment effects on the contact lenses. A large exposure and dense patterning of contact lens result in decreased (down to a minimum of 45%) in the light transmittance, which dictates the practical usability of such patterning. Surface treatment of contact lenses can be utilized to deposit stable conducting connection for onlensLEDs, displays, and communication antennas as well as for stabilizing biosensing materials and drug dispensing applications. 

 

 

 

 

المؤتمرات العلمية:

 

المؤتمر (1):

 

عنوان المؤتمر:

Nanotech,Biotech And Surtech Middle East 2017 Conference And Exhibition                      

تاريخ الإنعقاد:

04/12/2017

مكان الإنعقاد:

Dubai. UAE

طبيعة المشاركة:

Poster presentation

عنوان المشاركة:

Optical Glucose Sensors Based On Imprinted Nanopatterns In Hydrogel System

ملخص المشاركة:

Hydrogel-based systems have emerged as a reusable sensing platform to quantify biomarkers in high-risk patients at clinical and point-of-care settings. The capability to integrate hydrogel-based systems with optical transducers will provide quantitative and colorimetric measurements via spectrophotometric analyses of biomarkers. Here, we created an imprinting method to rapidly produce 2.5D photonic concavities in phenylboronic acid functionalized hydrogel films (Figure 1). Our method exploited diffraction properties of a hexagonally-packed 2.5D photonic microscale concavities having a lattice spacing of 3.3 µm. Illumination of the 2.5D hexagonally-packed structure with a monochromatic light source in transmission mode allowed reversible and quantitative measurements of variation in the concentration of glucose based on first order lattice interspace tracking. Reversible covalent phenyboronic acid coupling with cis-diols of glucose molecules expanded the hydrogel matrix by ~ 2% and 34% in the presence of glucose concentrations of 1 mM and 200 mM, respectively. A Donnan osmotic pressure induced volumetric expansion of the hydrogel matrix due to increasing glucose concentrations (1-200 mM) resulted in a nanoscale modulation of the lattice interspace, and shifted the diffraction angle (~ 45° to 36°) as well as the diffraction orders (~ 8 to 3 mm). The sensor exhibited a maximum lattice spacing diffraction shift within a response time of 15 min in a reversible manner. The developed 2.5D photonic sensors may have application in medical point-of-care diagnostics, implantable chips, and wearable continuous glucose monitoring devices.

 

 

المؤتمر (2):

 

عنوان المؤتمر:

FEAST International Conference On Design, Engineering, Basic & Applied Sciences And Information Technology: Challenges In Globalized Digital Era (DEA-19)                      

تاريخ الإنعقاد:

12/01/2019

مكان الإنعقاد:

London.UK

طبيعة المشاركة:

Poster presentation

عنوان المشاركة:

Laser-Induced Surface Modification Of Contact Lenses For Measuring Intraocular Pressure For Glaucoma Patients

ملخص المشاركة:

The aim of this project is to investigate the feasibility of using channels to measure intraocular pressure change for glaucoma patients. . Selective areas of the surface of commercial silicon-hydrogel contact lenses were patterned in array formats using different powers of the CO2 laser. 1D arrays of different groove densities, ring-shaped channels, were fabricated. Surface profile properties had different the space gap between the fabricated ring-shaped channels, which were controlled by the beam exposure time, beam power, and scan speed. The CO2 laser was used to create channels on the surface of the contact lenses. Via refinement of laser parameters, the surface geometry of polymer contact lens has obtained an excellent level of channels that may led to hydrophilic and intraocular pressure (IOP) measurable characteristics. A novel technique in fabricating contact lenses having excellent quality via the use of a continuous CO2 laser (λ=μm, Power=W and Speed=mm/s) is detailed here.

 

 

المرفقالحجم
Nanotech,Biotech and Surtech Middle East 2017 Conference and Exhibition.pdf‏295.34 ك.بايت
The_FEAST_conference_London-Yousef_Alqurashi.jpg‏57.11 ك.بايت