High resolution fluorescence bio-imaging upconversion nanoparticles in insects
Imaging fluorescent markers with brightness, photostability, and continuous emission with auto fluorescence background suppression in biological samples has always been challenging due to limitations of available and economical techniques. Here we report a new approach, to achieve high contrast imaging inside small and difficult biological systems with special geometry such as fire ants, an important agricultural pest, using a homemade cost-effective optical system. Unlike the commonly used rare-earth doped fluoride nanoparticles, we utilized nanoparticles with a high upconversion efficiency in water. Specifically Y_2O_3:Er^(+3),Yb^(+3) nanoparticles (40-50 nm diameter) were fed to fire ants as food and then a simple illuminating experiment was conducted at 980 nm wavelength at relatively low pump intensity 8 kW.cm^(−2). The locations were further confirmed by X-ray tomography, where most particles aggregated inside the ant's mouth. High resolution, fast, and economical optical imaging system opens the door for studying more complex biological systems
© 2017 Optical Society of America. Received 17 Oct 2016; revised 25 Nov 2016; accepted 25 Nov 2016; published 12 Jan 2017. YYC was partially sponsored by the ALS fellowship. JMG was supported by the Provost's Assigned Time for Research (Summer 2016), and the California State University Fresno, Research, Scholarship and Creative proposal Award (2014-2016). JJP was supported by a CSUF Provost's Undergraduate Research award (2014 −2016). The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. This work was partially sponsored by the Texas A&M Strategic Seed Grants program.
Published - oe-25-2-1030.pdf