Comprehensive bioimaging with fluorinated nanoparticles using breathable liquids

Abstract

Fluorocarbons are lipophobic and non-polar molecules that exhibit remarkable bio-compatibility, with applications in liquid ventilation and synthetic blood. The unique properties of these compounds have also enabled mass spectrometry imaging of tissues where the fluorocarbons act as a Teflon-like coating for nanostructured surfaces to assist in desorption/ionization. Here we report fluorinated gold nanoparticles (f-AuNPs) designed to facilitate nanostructure imaging mass spectrometry. Irradiation of f-AuNPs results in the release of the fluorocarbon ligands providing a driving force for analyte desorption. The f-AuNPs allow for the mass spectrometry analysis of both lipophilic and polar (central carbon) metabolites. An important property of AuNPs is that they also act as contrast agents for X-ray microtomography and electron microscopy, a feature we have exploited by infusing f-AuNPs into tissue via fluorocarbon liquids to facilitate multi-modal (molecular and anatomical) imaging.

On-Tissue Derivatization via Electrospray Deposition for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Endogenous Fatty Acids in Rat Brain Tissues

“… 18 , 20 , 23 However, these techniques may restrict detection of other classes of analytes compared to traditional matrixes, 24 frequently due to their affinity for specific classes of molecules 21 , 22 , 25 or fragmentation of higher molecular weight analytes. 26 , 27 Moreover, few of these approaches have been applied to the characterization of FFAs by MSI. 21 , 22 Time-of-flight (TOF)-SIMS is commonly utilized for FFA imaging in tissue sections but typically fragments large molecular ions.…”

A layer-by-layer assembled MoS2 thin film as an efficient platform for laser desorption/ionization mass spectrometry analysis of small molecules

“…38–40 As an example, AuNPs functionalized with perfluoroalkane thiol provided higher LDI-MS efficiency than citrate-stabilized AuNPs. 41 The surface of MoS 2 nanoflakes can be also modified with thiol derivatives through the coordination of thiol group to their defect sites or physisorption. 42,43 This surface modification strategy has been extensively employed for the cancer therapy and antibacterial application by using MoS 2 nanoflakes.…”

Long-pulse laser launch and ionization of tailored large neutral silver nanoparticles with atomic mass assignment

“…A tentative explanation for the underlying mechanism may be found in analogy to a recent study where perfluoroalkylated gold nanoparticles were used as a decomposing matrix to softly launch small biomolecules: a nanosecond UV laser pulse detached the ligands from the gold particles and provided an expanding perfluorinated matrix to launch the analyte biomolecules. 41 Here we propose that a similar mechanism may also be at work, however with the analyte particles providing their own matrix and the nanosecond laser pulse being replaced by millisecond laser heating. Earlier studies using microfocus laser sources showed that at laser intensities of 3 MW cm −2 thin layers of dye molecules could be heated to about 1000 K and evaporated intactly.…”