We are seeking for a physicist with expertise in experimental nanophotonics, plasmonics and/or optical trapping. The successful candidate will be responsible for the development of the nanooptical trapping microscope combined to single molecule fluorescence spectroscopy. He/She will take part in the experiment development, nano-optical trap characterization, and fluorescence analysis. The position is offered for 3 years and can be extended.
To strengthen our multidisciplinary team, we are seeking a biochemist or biophysicist with expertise in protein chemistry or protein biophysics. The successful candidate will be responsible for the preparation of the protein samples with or without external fluorescence labelling. He/She will also take part in spectroscopy characterization experiments taking advantage of the most recent advances in nano-optics and single molecule fluorescence analysis using techniques such as FCS, TCSPC, FLIM and FRET. The position is offered for 3 years and can be extended.
Enzyme-linked immunosorbent assay (ELISA) is the workhorse of current immunodetection. However, ELISA demands multiple steps of sample incubation and washing cycles, which makes the whole process time-consuming and labor-intensive.
Our new Analyst publication “Single-step homogeneous immunoassay for detecting prostate-specific antigen using dual-color light scattering of metal nanoparticles” reports a novel immunoassay technique that is significantly faster and simpler than ELISA, without compromising on the assay sensitivity.
- This novel technique performs immunosensing in a single-step in homogeneous phase. No rinsing, no washing are involved. Its operation is remarkably simple: Mix-Incubate-Detect.
- We detect where ELISA is not sensitive enough, down to the sub-picomolar regime while keeping the workflow simple and fast.
- The demonstration of PSA detection is highly relevant for monitoring cancer recurrence after radical prostatectomy, when the PSA blood concentration reaches values below the ELISA limit of detection. It is straightforward to implement for point-of-care monitoring of cancer evolution.
Planar plasmonic antennas resolve transient nanoscopic phase separation in biological lipid membranes
Nanoscopic domains (also known as lipid rafts) in living cell membranes have been postulated to play major roles in regulating a large variety of biological functions. However, the underlying basis for their formation remains under heavy debate because their typical sizes and characteristic times are below the resolution of standard microscopes.
In a recent ACS Nano publication entitled Transient Nanoscopic Phase Separation in Biological Lipid Membranes Resolved by Planar Plasmonic Antennas, we report on the application of in-plane plasmonic antenna arrays with different nanogap sizes in combination with fluorescence correlation spectroscopy (FCS) to assess the dynamic nanoscale organization of mimetic biological membranes. Our approach takes advantage of the highly enhanced and confined excitation light provided by dimer nano-antennas together with their outstanding planarity to investigate membrane regions as small as 10 nm in size with microsecond time resolution.
- We show the existence of transient nanoscopic domains in both liquid-order and liquid-disorder phases of mimetic biological membranes, featuring characteristic sizes of 10 nm with residence times between 30 µs and 150 µs
- Our planar optical antenna methodology provides nanoscale observation areas with microsecond time resolution and full biocompatibility. This constitutes a significant step forward in our ability to address native biological membranes with unprecedented spatiotemporal resolution.