Ultima, Bruker Nano

Characteristics

    • Laser: Mai Tai (Ti:Sapphire) manufactured by SpectraPhysics
      • 100fs pulse width
      • 80MHz repetition rate
      • 740 – 910nm
    • 4 detection channels: 2 GaAsPs +2 Multi Alkali PMTs
    • Software: Prairie View
    • Available objectives:
      • 20x water immersion objective (Olympus XLUMPLFL, NA 0.95 )
      • 40x water immersion objective (Olympus LUMPLANFL/IR 40 W, NA 0.8)
      • 4x air objective (NA 0.28)

OCTOPμS, built in-house

( Optical Coherence Tomography / Oxygen Pressure μ-scope)

Characteristics

  • Two-Photon microscope:
    • Laser: InSight DeepSee, Spectra Physics, two outputs: tunable 680-1300 nm and fixed 1040 nm
    • 4 PMT detectors covering the 440-800 nm emission spectral range,including:
      • 1 GaAsP for photon-counting phosphorescence lifetime measurements (for pO2 imaging) and for deep RBC flux measurements
      • 1 hybrid photon counting PMT for NADH fluorescence lifetime microscopy
      • 2 Multi Alkali PMTs for intensity-based imaging
  • Spectral Domain Optical Coherence Tomography
    • Light source: SLD, λ0 = 1300nm, Δλ > 170nm
    • Tuned for blood flow imaging simultaneously with the 2-Photon Microscopy imaging
  • Intrinsic Optical Signal Imaging (IOSI)
  • Laser-Speckle Flowmetry
  • Confocal Microscopy

Yaseen MA, Srinivasan VJ, Gorczynska I, Fujimoto JG, Boas DA, Sakadžic S. Multimodal optical imaging system for in vivo investigation of cerebral oxygen delivery and energy metabolism. Biomed Opt Express. 2015 Dec 01; 6(12):4994-5007. Schematic

Principle

Applications

 

PO2 imaging

 

Top views of the two cortical microvascular stacks with the labeled microvascular segments: arterioles (red), capillaries (green), and venules (blue). (c, e) PO2 measurements during normocapnia (c) and hypercapnia (e) overlaid over microvascular structures presented in b and d, respectively. Black squares in b and d represent PO2 measurement fields of view presented in c and e, respectively. In gray-colored vessels PO2 was not estimated. Scale bars, 200 μm. [Sakadžić et al. 2014]
 

NADH imaging

Applying 2PM for measuring endogenous fluorescence of reduced nicotinamide adenine dinucleotide (NADH) has demonstrated utility as a minimally invasive technique for evaluating metabolic activity.

(a-d) Representative fluorescence intensity images of (a,b) endogenous NADH fluorescence and (c,d) the topically-applied astrocyte label sulforhodamine 101 in the anesthetized rat cerebral cortex. Imaging was performed (a,c) before and (b,d) after BMI-induced focal seizure activity, Scale bar: 50 μm [Gomez et al. 2018]

Deep Red Blood Cell (RBC) flux imaging

A far-red fluorophore such as Alexa680 and photon-counting detection can be used to measure capillary red blood cell flux in both cerebral gray and white matter.

1.4-mm-thick in vivo Alexa680-labeled mouse brain microvasculature. [Li et al. 2019]