This work presents a ZnO-coated no-core optical fiber sensor (OFS) designed for the highly sensitive detection of acetone vapor. Acetone is a key biomarker for diabetes, which is linked to blood glucose levels and can be detected non-invasively through breath analysis. The OFS utilizes a no-core fiber (NCF) as the sensing region, coated with a thin layer of ZnO nanoparticles to enhance evanescent field interaction with the VOCs at the fiber interface.
View Article and Find Full Text PDFA non-invasive optical fiber sensor for detecting volatile organic compounds (VOCs) as biomarkers of diabetes is proposed and experimentally demonstrated. It offers a low-cost and straightforward fabrication approach by implementing a one-step spray coating of a ZnO colloidal solution on a glass optical fiber. The structure of the optical fiber sensor is based on a single-mode fiber-coreless silica fiber-single-mode fiber (SMF-CSF-SMF) structure, where the CSF is the sensor region spliced between two SMFs.
View Article and Find Full Text PDFIn general, volatile organic compounds (VOCs) have a high vapor pressure at room temperature (RT). It has been reported that all humans generate unique VOC profiles in their exhaled breath which can be utilized as biomarkers to diagnose disease conditions. The VOCs available in exhaled human breath are the products of metabolic activity in the body and, therefore, any changes in its control level can be utilized to diagnose specific diseases.
View Article and Find Full Text PDFThis work demonstrated a ZnO-coated optical fiber sensor for the detection of a volatile organic compound (VOC) biomarker for diabetes for detecting isopropanol (IPA) markers. A coreless silica fiber (CSF) was connected to a single-mode fiber (SMF) at both ends to achieve a SMF-CSF-SMF structure. CSF is the sensing region where multimode interference (MMI) generates higher light interaction at the interface between the fiber and sensing medium, leading to enhanced sensitivity.
View Article and Find Full Text PDFThe increasing use of nanomaterials and scalable, high-yield nanofabrication process are revolutionizing the development of novel biosensors. Over the past decades, researches on nanotechnology-mediated biosensing have been on the forefront due to their potential application in healthcare, pharmaceutical, cell diagnosis, drug delivery, and water and air quality monitoring. The advancement of nanoscale science relies on a better understanding of theory, manufacturing and fabrication practices, and the application specific methods.
View Article and Find Full Text PDFThis study aims to investigate the validity and reliability of a novel plastic optical fiber (POF) sensor, which was developed to measure the angles of flexion, extension and lateral bend at the lumbar region. The angles of flexion, extension and lateral bend for a standing position were measured simultaneously using both the novel POF sensor of this investigation and the commercial Biometrics goniometer instrument. Each movement had two steps of bending which were 10° and 20° based on inclinometer readings.
View Article and Find Full Text PDFA comprehensive study of the effect of a wide range of controlled human subject motion on Photoplethysmographic signals is reported. The investigation includes testing of two separate groups of 5 and 18 subjects who were asked to undertake set exercises whilst simultaneously monitoring a wide range of physiological parameters including Breathing Rate, Heart Rate and Localised Blood Pressure using commercial clinical sensing systems. The unique finger mounted PPG probe equipped with miniature three axis accelerometers for undertaking this investigation was a purpose built in-house version which is designed to facilitate reproducible application to a wide range of human subjects and the study of motion.
View Article and Find Full Text PDFA full-vectorial H-field formulation-based finite element approach is used to optimize a biosensor structure incorporating a horizontal slot waveguide. It is designed to detect DNA hybridization through the change of the effective index of the waveguide structure. The key parameters, such as normalized power confinement, power density, change in effective index, and sensitivity are presented by optimizing the device parameters of the slot waveguide.
View Article and Find Full Text PDFAn optical transducer using an integrated optics polymer nanowire is proposed. The nanoimprint technique is used to fabricate an OrmoComp nanowire with 1.0 μm width and 0.
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