Optical fiber surface-enhanced Raman scattering (SERS) probes provide a novel platform for liquid-phase in situ and remote SERS detections. However, it is still a challenge to fabricate noble metal nanostructures with large SERS enhancement factor (EF) onto optical fiber surfaces. In this article, we successfully prepare Au-nanorod cluster structures on optical fiber facets by a laboratory-developed laser-induced evaporation self-assembly method. It is demonstrated that the optimized optical fiber SERS probes show high detection sensitivity (10 M for rhodamine 6G solution, and 10 M for malachite green or crystal violet solution) and excellent reproducibility (relative standard deviation less than 6%). As the laser-induced evaporation self-assembly method is a simple and low-cost method capable of achieving automatic and reproducible preparations of cluster patterned optical fiber SERS probes, this work may find important application prospects in various liquid-phase SERS detection areas.
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http://dx.doi.org/10.1364/OE.386215 | DOI Listing |
Background: Despite an aging population, it remains challenging to reliably differentiate between loss of cognitive function associated with normal aging and cognitive decline associated with pathologic processes. With growing interest in using retinal and optic nerve biomarkers to diagnose neurodegenerative diseases, characterization of the velocity of normal retinal age-related changes will further our understanding. We evaluated longitudinal microvascular changes in cognitively normal older adults using optical coherence tomography (OCT) and OCT angiography (OCTA).
View Article and Find Full Text PDFBackground: Mild cognitive impairment (MCI) is currently a clinical diagnosis characterized by decline in memory and daily cognitive function from baseline. Exploratory studies using optical coherence tomography angiography have reported alterations in the retinal capillary plexus vessel density and attenuation of the retinal nerve fiber layer, but these results appear to be mixed. We used ultra-widefield (UWF) imaging to evaluate retinal and choroidal vasculature and structure in individuals with mild cognitive impairment (MCI) compared to controls with normal cognition.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Ophthalmology, Myongji Hospital, Hanyang University College of Medicine, Goyang, Korea, Republic of (South).
Background: Spectrum Domain-Optical Coherence Tomography (SD-OCT) is a non-invasive technology that acquires cross-sectional images of retinal structures allowing neural fundus integrity assessment. Macular thickness and retinal nerve fiber layer (RNFL) thickness measured by an SD-OCT have been used as a indicator of Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI). However which portion of retinal RNFL is the most sensitive area among normal control, aMCI and AD is not clear yet.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
Background: The early detection of preclinical dementia is crucial, prompting investigations into retinal biomarkers using optical coherence tomography (OCT). Inconsistent and limited longitudinal studies have been done to clarify the association between the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GC-IPL) thickness and cognitive function over time. This study aims to explore the association between retinal biomarkers and cognitive function over time in non-demented older adults.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA.
Background: Recent evidence suggests extensive myelin dysfunction in Alzheimer's Disease (AD), lending to investigation of biomarkers previously implicated in both AD and Multiple Sclerosis (MS) to find objective and obtainable diagnostic screening tools. Glial fibrillary acidic protein (GFAP), Chitinase-3-like protein 1 (CHI3L1), Chemokine (C-X-C motif) ligand 13 (CXCL13), and neurofilament light chain (Nfl) have been known to mark neuronal pathology in both diseases making them attractive markers. Retinal Optical Coherence Tomography (OCT) becomes a popular diagnostic tool in both conditions as an inexpensive and rapid way of obtaining a window into the cerebrum.
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