Quantitative Imaging of Specific Proteins in the Human Retina by Laser Ablation ICPMS using Bioconjugated Metal Nanoclusters as Labels.
María Cruz-AlonsoBeatriz FernándezMontserrat GarcíaHéctor González-IglesiasRosario PereiroPublished in: Analytical chemistry (2018)
A sensitive methodology using antibody-conjugated gold nanoclusters (AuNCs) was developed for the quantitative bioimaging of specific proteins in biological tissues by laser ablation (LA) coupled to inductively coupled plasma-mass spectrometry (ICPMS). Determination of metallothioneins (MT1/2 protein isoforms) images in human retina tissue sections was carried out as a proof of concept. AuNCs used as label were conjugated to the selected antibody through carbodiimide coupling. A stoichiometry of AuNCs/available antibody of 1:1 was obtained. The high amplification provided by AuNC labels allowed for obtaining the distribution of MT1/2 in the neurosensory retina layers (5 μm thick sections) by LA-ICPMS. Elemental images of 197Au+ were quantified with gelatin matrix-matched standards and then converted to 2D quantitative images of MT1/2 concentration. For validation purposes, average concentrations of MT1/2 obtained in the human retinal layers by LA-ICPMS were successfully compared with those obtained with a commercial ELISA kit.
Keyphrases
- endothelial cells
- high resolution
- optical coherence tomography
- diabetic retinopathy
- mass spectrometry
- deep learning
- convolutional neural network
- induced pluripotent stem cells
- pluripotent stem cells
- sensitive detection
- photodynamic therapy
- fluorescent probe
- gene expression
- small molecule
- amino acid
- room temperature
- radiofrequency ablation
- high performance liquid chromatography
- protein protein
- liquid chromatography
- energy transfer
- living cells
- molecularly imprinted