title: Spectroscopic super-resolution fluorescence cell imaging using ultra-small Ge quantum dots.
abstract: We demonstrate a spectroscopic imaging based super-resolution approach by separating the overlapping diffraction spots into several detectors during a single scanning period and taking advantage of the size-dependent emission wavelength in nanoparticles. This approach has been tested using off-the-shelf quantum dots (Invitrogen Qdot) and in-house novel ultra-small (~3 nm) Ge QDs. Furthermore, we developed a method-specific Gaussian fitting and maximum likelihood estimation based on a Matlab algorithm for fast QD localisation. This methodology results in a three-fold improvement in the number of localised QDs compared to non-spectroscopic images. With the addition of advanced ultra-small Ge probes, the number can be improved even further, giving at least 1.5 times improvement when compared to Qdots. Using a standard scanning confocal microscope we achieved a data acquisition rate of 200 ms per image frame. This is an improvement on single molecule localisation super-resolution microscopy where repeated image capture limits the imaging speed, and the size of fluorescence probes limits the possible theoretical localisation resolution. We show that our spectral deconvolution approach has a potential to deliver data acquisition rates on the ms scale thus providing super-resolution in live systems.
authors.forename: Mingying
authors.initials: M
authors.lastname: Song
authors.forename: Ali
authors.initials: A
authors.lastname: Karatutlu
authors.forename: Isma
authors.initials: I
authors.lastname: Ali
authors.forename: Osman
authors.initials: O
authors.lastname: Ersoy
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Yang
authors.forename: Yuanpeng
authors.initials: Y
authors.lastname: Zhang
authors.forename: William R
authors.initials: WR
authors.lastname: Little
authors.forename: Ann P
authors.initials: AP
authors.lastname: Wheeler
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Sapelkin
mesh_terms: D005453:Fluorescence; D016013:Likelihood Functions; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence