Persistent Luminescent Nanoparticle-Loaded Filaments for Identification of Fabrics in the Visible and Infrared.

Persistent luminescent materials are those which can store an amount of energy locally and release it slowly in the form of light. In this work, persistent luminescent nanoparticles (PLNPs) were synthesized and incorporated into polypropylene (PP) filaments at various loading percentages. We investigated the optical properties of both the as-prepared PLNPs and the PLNP-loaded filaments, focusing on any changes resulting from the integration into the filaments.

Variables Affecting the Extraction of Antioxidants in Cold and Hot Brew Coffee: A Review.

Coffee beans are a readily available, abundant source of antioxidants used worldwide. With the increasing interest in and consumption of coffee beverages globally, research into the production, preparation, and chemical profile of coffee has also increased in recent years. A wide range of variables such as roasting temperature, coffee grind size, brewing temperature, and brewing duration can have a significant impact on the extractable antioxidant content of coffee products.

Quantification of Spent Coffee Ground Extracts by Roast and Brew Method, and Their Utility in a Green Synthesis of Gold and Silver Nanoparticles.

Nanotechnology has become increasingly important in modern society, and nanoparticles are routinely used in many areas of technology, industry, and commercial products. Many species of nanoparticle (NP) are typically synthesized using toxic or hazardous chemicals, making these methods less environmentally friendly. Consequently, there has been growing interest in green synthesis methods, which avoid unnecessary exposure to toxic chemicals and reduce harmful waste.

Effect of surface coating of KYb2F7:Tm(3+) on optical properties and biomedical applications.

This project aims to provide an insight on the effects of biocompatible polymers on the optical properties and the nanoparticle-cell interaction of KYb2F7:Tm(3+) nanocrystals that exhibit strong near infrared (NIR) fluorescence. KYb2F7:Tm(3+) nanocrystals were synthesized with a diameter of 20-30 nm and surface modified with poly(ethylene glycol), Pluronic(®) F-127, and poly(N-vinylpyrrolidone), due to the associated advantages. Some of these include biocompatibility and biodistribution in the instance of agglomeration and hydrophobicity as well as the addition of a targeting agent and drug loading by further functionalization.

Depth-Resolved Multispectral Sub-Surface Imaging Using Multifunctional Upconversion Phosphors with Paramagnetic Properties.

Molecular imaging is very promising technique used for surgical guidance, which requires advancements related to properties of imaging agents and subsequent data retrieval methods from measured multispectral images. In this article, an upconversion material is introduced for subsurface near-infrared imaging and for the depth recovery of the material embedded below the biological tissue. The results confirm significant correlation between the analytical depth estimate of the material under the tissue and the measured ratio of emitted light from the material at two different wavelengths.

Accurate Identification and Selective Removal of Rotavirus Using a Plasmonic-Magnetic 3D Graphene Oxide Architecture.

According to the World Health Organization, even in the 21st century, more than one million children die each year due to the rotavirus contamination of drinking water. Therefore, accurate identification and removal of rotavirus are very important to save childrens' lives. Driven by the need, in this Letter, we report for the first time highly selective identification and removal of rotavirus from infected water using a bioconjugated hybrid graphene oxide based three-dimensional (3D) solid architecture.

Interphotoreceptor retinoid-binding protein protects retinoids from photodegradation.

Retinol degrades rapidly in light into a variety of photoproducts. It is remarkable that visual cycle retinoids can evade photodegradation as they are exchanged between the photoreceptors, retinal pigment epithelium and Müller glia. Within the interphotoreceptor matrix, all-trans retinol, 11-cis retinol and retinal are bound by interphotoreceptor retinoid-binding protein (IRBP).

Bimodal Imaging Using Neodymium Doped Gadolinium Fluoride Nanocrystals with Near-Infrared to Near-Infrared Downconversion Luminescence and Magnetic Resonance Properties.

Here we report the synthesis, characterization and application of a multifunctional surface functionalized GdF:Nd nanophosphor that exhibits efficient near infrared (NIR) fluorescence as well as magnetic properties, which can be utilized for bimodal imaging in medical applications. The nanoparticles are small with an average size of 5 nm and form stable colloids that last for several weeks without settling, enabling the use for several biomedical and photonic applications. Their excellent NIR properties, such as nearly 11 % quantum yield of the 1064 nm emission, make them ideal contrast agents and biomarkers for and NIR optical bioimaging.

Rare Earth doped nanoparticles in imaging and PDT.

Nanoparticles doped with rare earth ions for biomedical imaging and infrared photodynamic therapy (IRPDT) have been synthesized, characterized, and compared. Specifically, these nanoparticles utilize two primary modalities: near infrared excitation and emission for imaging, and near infrared upconversion for photodynamic therapy. These nanoparticles are optimized for both their infrared emission and upconversion energy transfer to a photoactive agent conjugated to the surface.

Optical and spectroscopic properties of human whole blood and plasma with and without Y₂O₃ and Nd³⁺:Y₂O₃ nanoparticles.

The optical properties of human whole blood and blood plasma with and without Y₂O₃ and Nd³⁺:Y₂O₃ nanoparticles are characterized in the near infrared region at 808 nm using a double integrating sphere technique. Using experimentally measured quantities of diffuse reflectance and diffuse transmittance, a computational analysis was conducted utilizing the Kubelka-Munk, the Inverse Adding Doubling, and Magic Light Kubelka-Munk and Monte Carlo Methods to determine optical properties of the absorption and scattering coefficients. Room temperature absorption and emission spectra were also acquired of Nd³⁺:Y₂O₃ nanoparticles elucidating their utility as biological markers.

Popcorn-shaped magnetic core-plasmonic shell multifunctional nanoparticles for the targeted magnetic separation and enrichment, label-free SERS imaging, and photothermal destruction of multidrug-resistant bacteria.

Over the last few years, one of the most important and complex problems facing our society is treating infectious diseases caused by multidrug-resistant bacteria (MDRB), by using current market-existing antibiotics. Driven by this need, we report for the first time the development of the multifunctional popcorn-shaped iron magnetic core-gold plasmonic shell nanotechnology-driven approach for targeted magnetic separation and enrichment, label-free surface-enhanced Raman spectroscopy (SERS) detection, and the selective photothermal destruction of MDR Salmonella DT104. Due to the presence of the "lightning-rod effect", the core-shell popcorn-shaped gold-nanoparticle tips provided a huge field of SERS enhancement.

Effect of Silver Coating on Barium Titanium Oxide Nanoparticle Toxicity.

Nanoparticles are presently being studied for optical and biomedical applications such as medical imaging and drug delivery. Nanoparticles impact the cellular environment due to many variables such as size, shape, and composition. How these factors affect cell viability is not fully understood.

Enhancement of nonlinear optical properties of BaTiO3 nanoparticles by the addition of silver seeds.

Barium titanate (BaTiO3) is a technologically important material because of its nonlinear properties, such as its strong second harmonic generation and high third order susceptibility. While many nonlinear effects have been extensively studied on the bulk scale, there are still questions regarding the strength of nonlinear effects in nanoparticles. The nonlinear properties of BaTiO3 nanoparticles and nanorods have been studied using the closed aperture z-scan technique.

Optical absorption and scattering of bovine cornea, lens, and retina in the near-infrared region.

The optical properties of bovine ocular tissues have been determined at laser wavelengths in the near-infrared (NIR) region. The inverse adding doubling (IAD), Kubelka-Munk (KM), and inverse Monte Carlo (IMC) methods were applied to the measured values of the total diffuse transmission, total diffuse reflection, and collimated transmission to determine the optical absorption and scattering coefficients of the bovine cornea, lens and retina from 750 to 1,000 nm using a CW Ti:sapphire laser. The optical properties obtained from these three methods have been compared and are discussed.

A Comparison of Methods for Determining Optical Properties of Thin Samples.

The near-infrared (NIR) optical properties of human retinal pigmented epithelial (RPE) cells and rare earth nanopowders were studied using a double-integrating sphere setup. The Kubelka-Munk and Inverse Adding-Doubling techniques were applied to obtain absorption and scattering coefficients. These are compared with the coefficients obtained through the Representative Layer Theory described by the Dahm equation.

Optical absorption and scattering of bovine cornea, lens and retina in the visible region.

Optical properties of bovine ocular tissues were determined at laser wavelengths in the visible region. The inverse adding doubling (IAD), Kubelka-Munk (KM), and inverse Monte Carlo (IMC) methods were applied to the measured values of the total diffuse transmission, total diffuse reflection, and collimated transmission to determine the optical absorption and scattering coefficients of the bovine cornea, lens and retina at 457.9 nm, 488 nm, and 514.