An optical sensor for reactive oxygen species: encapsulation of functionalised silica nanoparticles into silicate nanoprobes to reduce fluorophore leaching.
Sol-gel nanoprobes, also known as Photonic Explorer for Bioanalysis with Biologically Localised Embedding (PEBBLE), capable of performing in-vitro intracellular monitoring of reactive oxygen species have been developed using a modified form of 5(6)-carboxyfluorescein diacetate. A sol-gel matrix was selected for the design of the probes as it is photostable, optically transparent and chemically inert, and to minimise leaching of the dye from the porous matrix it was covalently immobilised to silica nanoparticles (15 nm). Using this approach, 0.1% of the dye was found to leach over a typical analysis time of 5 h and minimal photobleaching was observed. In addition, the nanoprobes were shown to respond to hydrogen peroxide, hydroxyl anions, nitric oxide, peroxynitrile and superoxide anions, obtaining limits of detection of 2.2, 1.1, 3.2, 1.1 and 1.1 nM respectively. The nanoprobes were subsequently introduced into bovine oviducts using a lipid transfection reagent (Escort IV) and fluorescence was observed.
Hammond
Victoria J
VJ
Department of Chemistry, The University of Hull, Cottingham Road, Hull, UK HU6 7RX.
Aylott
Jonathan W
JW
Greenway
Gillian M
GM
Watts
Paul
P
Webster
Abigail
A
Wiles
Charlotte
C
D000818:Animals; D015374:Biosensing Techniques; D002417:Cattle; D005187:Fallopian Tubes / Q000737:chemistry; D005260:Female; D005456:Fluorescent Dyes; D053758:Nanoparticles; D036103:Nanotechnology; D017382:Reactive Oxygen Species / Q000032:analysis*; D017640:Silicates; D012822:Silicon Dioxide
D005456:Fluorescent Dyes; D017382:Reactive Oxygen Species; D017640:Silicates; D012822:Silicon Dioxide