No abstract

YAG:Ce3+ nanoparticles 9.5+/-1.2 nm in diameter have been synthesized from aluminium isopropoxide and acetates of yttrium and cerium in 1,4-butanediol (1,4-BD) by autoclave treatment at 300 degrees C for 2 h. After replacing 1,4-BD by ultrapure water, NH2 groups were introduced on the surface of YAG:Ce3+ nanoparticles by addition of 3-aminopropyltrimethoxysilane then biotinylation with sulfo-NHS-LC-biotin. We demonstrated that avidin immobilized beads are tagged by biotinylated YAG:Ce3+ nanoparticles by the selective avidin-biotin interaction, furnishing a green fluorescent image on excitation with blue light. This result indicates that YAG:Ce3+ nanoparticle phosphors have much potential in biological applications.

We developed an immunochromatographic assay kit that uses fluorescent silica nanoparticles bound to anti-Acanthamoeba antibodies (fluorescent immunochromatographic assay [FICGA]) and evaluated its efficacy for the detection of Acanthamoeba and diagnosis of Acanthamoeba keratitis (AK). The sensitivity of the FICGA kit was evaluated using samples of Acanthamoeba trophozoites and cysts diluted to various concentrations. A conventional immunochromatographic assay kit with latex labels (LICGA) was also evaluated to determine its sensitivity in detecting Acanthamoeba trophozoites. To check for cross-reactivity,

No abstract

Poly(methyl methacrylate) beads were hybridized with Y 3 Al 5 O 12 :Ce 3þ nanoparticles through electrostatic interactions using the layer-by-layer adsorption technique to prepare fluorescent beads for biological application. The subsequent sequential adsorption of poly(sodium 4-styrenesulfonate) and poly(allylamine hydrochloride) onto the composite beads prevented the detachment of the Y 3 Al 5 O 12 :Ce 3þ nanoparticles. The fluorescent beads were observed as tight dot plots by flowcytometry. Bovine serum albumin can be immobilized on the surface of the composite beads and tagged with a red dye through an antigen-antibody reaction. This result indicates that the composite beads are useful for bead assays such as flowcytometry.