Research

LANTHANIDE UP-CONVERTING PHOSPHORS

We have shown that we can put a gold coating onto a NaYF phosphor nanoparticle, doped with Er or Eu, and improve the emission efficiency by 10x. The gold-coated particles can be used for labeling in biology and for labeling high value items for security. They exhibit both a visual color and a phosphorescent emission under near-infrared light excitation. Our recent work has added a magnetic core to these materials for added functionality using magnetic fields.

ACCELERATED IMMUNOASSAYS IN ROTATING MICROCAPILLARIES WITHIN A MAGNETIC FIELD

Figure 1(c)

We have used magnetic particles to carry antibodies inside a rotating micro-capillary. The capillary rotates inside a stationary magnetic field. Under the right conditions of rotation speed and magnetic field strength, the particles align into long chains that are swept through the fluid in the capillary by continued alignment to the external magnetic field. The sweeping motion provides enhanced mixing and much faster immunoassays.

Figure 2c 1um fl image da

NANOPHOTONIC CRYSTAL SENSOR

An array of nanowells is fabricated in PMMA using electron beam lithography. Nanoparticles are deposited into each well using an electric field (electrophoresis). A solution to Maxwell's equations shows intense amplified electric fields around the particles that carry antibodies and fluorescence labels. With photon counting, we have been able to detect analytes such as cancer biomarkers, pesticide biomarkers and defects in DNA at the low attomolar level with a quick, simple assay using very little sample.


© Ian M Kennedy 2012