According to one method, a sample with cells contains a phototagging agent. The sample is imaged to identify at least one target cell to be isolated. The identified target cell in the sample is selectively irradiated with photo-activating light for selectively activating the phototagging agent in the target cell to change its fluorescence response. The irradiated target cell is isolated from other cells in the sample based on a difference in its fluorescence response compared to non-activated phototagging agent in the other cells. Further aspects are directed to a corresponding microscope system and chemical compound for use as the phototagging agent.

Amyloids have been known to arise from many different proteins and polypeptides. These polypeptide chains generally form β-sheet structures that aggregate into long fibers; however, identical polypeptides can fold into multiple distinct amyloid conformations. The diversity of the conformations may have led to different forms of the prion diseases. In particular, large populations of small globular amyloid oligomers (gOs) and curvilinear fibrils (CFs) precede the formation of late-stage rigid fibrils (RFs), and have been implicated in amyloid toxicity. As disclosed herein, triarylmethane f dye crystal violet is a highly selective indicator of gOs and CFs. Therefore, disclosed herein are compositions, kits, and methods for detecting amyloids in a tissue, either in vitro or in vivo.

Amyloids have been known to arise from many different proteins and polypeptides. These polypeptide chains generally form β-sheet structures that aggregate into long fibers; however, identical polypeptides can fold into multiple distinct amyloid conformations. The diversity of the conformations may have led to different forms of the prion diseases. In particular, large populations of small globular amyloid oligomers (gOs) and curvilinear fibrils (CFs) precede the formation of late-stage rigid fibrils (RFs), and have been implicated in amyloid toxicity. As disclosed herein, triarylmethane f dye crystal violet is a highly selective indicator of gOs and CFs. Therefore, disclosed herein are compositions, kits, and methods for detecting amyloids in a tissue, either in vitro or in vivo.

The present invention employs the technique for expansion microscopy (E×M) utilizing anchorable derivatives of hematoxylin and eosin (H&E) stained tissue specimens within tissue samples, in order to achieve high resolution detection of biomolecules with precise morphological features of cells and nuclei, which in turn, allows for effective for accurate early stage disease diagnosis including various cancers. Staining with H&E employs anchorable derivatives that can be cross-linked into the E×M hydrogel matrix.

The present invention employs the technique for expansion microscopy (E×M) utilizing anchorable derivatives of hematoxylin and eosin (H&E) stained tissue specimens within tissue samples, in order to achieve high resolution detection of biomolecules with precise morphological features of cells and nuclei, which in turn, allows for effective for accurate early stage disease diagnosis including various cancers. Staining with H&E employs anchorable derivatives that can be cross-linked into the E×M hydrogel matrix.

Provided is a multisignal labeling reagent comprising a first polymer covalently bound to (a) a reactive group or a first member of a first binding pair, and (b) more than one digoxigenin molecule.

Provided is a multisignal labeling reagent comprising a first polymer covalently bound to (a) a reactive group or a first member of a first binding pair, and (b) more than one digoxigenin molecule.

Provided is a composition comprising an analyte bound covalently or through a first binding pair to a polymer. In this composition, the analyte is less than about 2000 MW; the polymer further comprises more than one signal or first member of a second binding pair; and the analyte is not a member of the first binding pair or the second binding pair. Also provided is an assay for an analyte. The assay comprises: combining a sample suspected of containing the analyte with the above-described composition and a binding agent that binds to the analyte; and detecting the signal or the first member of the second binding pair that is bound to the binding agent. Additionally provided is a multisignal labeling reagent comprising a first polymer covalently bound to (a) a reactive group or a first member of a first binding pair, and (b) more than one digoxigenin molecule.

Provided is a composition comprising an analyte bound covalently or through a first binding pair to a polymer. In this composition, the analyte is less than about 2000 MW; the polymer further comprises more than one signal or first member of a second binding pair; and the analyte is not a member of the first binding pair or the second binding pair. Also provided is an assay for an analyte. The assay comprises: combining a sample suspected of containing the analyte with the above-described composition and a binding agent that binds to the analyte; and detecting the signal or the first member of the second binding pair that is bound to the binding agent. Additionally provided is a multisignal labeling reagent comprising a first polymer covalently bound to (a) a reactive group or a first member of a first binding pair, and (b) more than one digoxigenin molecule.

Here are described SkQ compounds containing cations of various types: alkyl(triphenyl)phosphonium cation, quaternary ammonium cations, including pH-dependent and permanent cations of rhodamines, berberine and palmatine alkaloids.