Addressing the pressing need for rapid and sensitive infectious disease diagnostics, we introduce DIgitAl plasMONic nanobubble Detection (DIAMOND), an innovative strategy harnessing plasmonic nanobubbles generated through laser-induced nanoparticles. Using gold nanoparticles in an optofluidic system, DIAMOND enables compartment-free digital counting and homogeneous immunoassays, demonstrating respiratory syncytial virus detection at single RNA copy per microliter. This breakthrough technology offers single-nanoparticle detection, direct virus sensing at room temperature, and simplified liquid handling, establishing itself as a versatile platform for expedited and highly sensitive diagnostics, with the added benefit of achieving detection within just 10 minutes. Concurrently, our research advances plasmonic nanobubble generation by anchoring sub-10 nm AuNPs onto thiol-rich Qβ virus-like particles, significantly enhancing photocavitation and reducing laser fluency. In a significant step forward, we are expanding the horizons of DIAMOND, now enabling single protein detection at attomolar concentrations, representing a remarkable advancement in our capabilities.
The brain is the most complex organ in the human body, and brain diseases are highly challenging to diagnose, monitor, and treat. Nanomaterials have emerged as a unique wireless interface with the brain in the micro/nanoscale. I will discuss our recent efforts to develop new tools using advanced nanomaterials and photonics to further understand and access the brain. These include exciting capabilities to remotely control protein activity, study neurochemical modulation, and change the blood-brain barrier permeability. These new tools provide insights into the brain microenvironment and a unique opportunity to develop strategies to treat brain diseases.
Diffusion of substances in the brain extracellular space (ECS) is important for extrasynaptic communication, extracellular ionic homeostasis, drug delivery, and metabolic waste clearance. However, substance diffusion is largely constrained by the geometry of brain ECS and the extracellular matrix. Investigating the diffusion properties of substances not only reveals the structural information of the brain ECS but also advances the understanding of intercellular signaling of brain cells. Among different techniques for substance diffusion measurement, the optical imaging method is sensitive and straightforward for measuring the dynamics and distribution of fluorescent molecules or sensors and has been used for molecular diffusion measurement in the brain. We mainly discuss recent advances of optical imaging-enabled measurements toward dynamic, anisotropic, high-resolution, and functional aspects of the brain ECS diffusion within the last 5 to 10 years. These developments are made possible by advanced imaging, such as light-sheet microscopy and single-particle tracking in tissue, and new fluorescent biosensors for neurotransmitters. We envision future efforts to map the ECS diffusivity across the brain under healthy and diseased conditions to guide the therapeutic delivery and better understand neurochemical transmissions that are relevant to physiological signaling and functions in brain circuits.
Biomedical applications of nanoparticle heating range in scale from molecular activation (i.e. molecular beacons, protein
denaturation, lipid melting and drug release), cellular heating (i.e. nanophotolysis and membrane permeability control
and rupture) to whole tumor heating (deep and superficial). This work will present a review on the heating of two
classes of biologically compatible metallic nanoparticles: iron oxide and gold with particular focus on spatial and
temporal scales of the heating event. The size range of nanoparticles under discussion will focus predominantly in the 10
- 200 nm diameter size range. Mechanisms of heating range from Néelian and Brownian relaxation due to magnetic
susceptibility at 100s of kHz, optical absorption due to VIS and NIR lasers and "Joule" heating at higher frequency RF
(13.56 MHz). The heat generation of individual nanoparticles and the thermal responses at nano-, micro-, and macroscales
are presented. This review will also discuss how to estimate a specific absorption rate (SAR, W/g) based on
individual nanoparticles heating in bulk samples. Experimental setups are designed to measure the SAR and the results
are compared with theoretical predictions.
Conference Committee Involvement (3)
Optical Fibers and Sensors for Medical Diagnostics, Treatment and Environmental Applications XXV
25 January 2025 | San Francisco, California, United States
Optical Fibers and Sensors for Medical Diagnostics, Treatment and Environmental Applications XXIV
27 January 2024 | San Francisco, California, United States
Optical Fibers and Sensors for Medical Diagnostics, Treatment and Environmental Applications XXIII
28 January 2023 | San Francisco, California, United States
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.