Two‐Photon Fluorescent Probes for Acidic Vesicles in Live Cells and Tissue

Abstract

Move with the groove: Two‐photon fluorescent pH probes and a two‐photon lysotracker (AL1) can visualize acidic vesicles in live cells and living tissue for a long period of time without mistargeting and photobleaching problems. Using AL1, vesicles can be tracked in real time (see picture).

A Fluorescent Indicator for Imaging Lysosomal Zinc(II) with Förster Resonance Energy Transfer (FRET)‐Enhanced Photostability and a Narrow Band of Emission

“…Compounds 3 and 4 contain a secondary or a tertiary amino group, respectively, as a lysosome-directing moiety. [20 ]…”

“…The detailed procedures are included in the Supporting Information. Briefly, the Horner–Wadsworth–Emmons reaction between 5 [10, 20] and aldehyde 8 [8c ] leads to compound 6 in 67% yield, which reacts with azide 9 [10] under the copper(I)-catalyzed conditions [21] to obtain 7 in 78% yield. Upon treatment with n -propylamine or morpholine, compound 7 is converted to compound 3 in 59% or 4 in 62% yield, respectively.…”

“…The inclusion of a secondary amino group in compound 3 elevates the Pearson’s coefficient to 56%, an apparent preference for lysosomes. Compound 4 , which contains a morpholino group extensively used for lysosome targeting, [20c, 28] achieves a higher Pearson’s coefficient of 67%. The two-channel overlay images of compounds 1, 3 , and 4 with FusionRed-LAMP are shown in Figure S14 of the Supporting Information.…”

Zweiphotonenabsorption und das Design von Zweiphotonenfarbstoffen

“…[79] Kürzlich wurden spezifische TPEFFarbstoffe für individuelle subzelluläre Strukturen und Organellen entwickelt. [80] Bei diesen Farbstoffen kommt es vor allem auf die Helligkeit [81] und Cho [82] [81] Seit kurzem versucht man, hoch selektive Zweiphotonensensoren für bestimmte Metallkationen, vor allem Zink, zu entwickeln. In einigen Fällen wird die Fluoreszenz durch Bindung des Kations unterdrückt, [83,84] in anderen erhöht die Chelatbildung sowohl d als auch F F .…”

Two-photon probes for biomedical applications

“…We have proposed a guideline for the design of a useful TP probe; it should have high selectivity for the biological targets, appreciable water solubility and cell permeability to stain the cells, and significant TP action cross section (a measure of TP excited fluorescence )undefined(TPEF) intensity emitted from the probe(4). In this context, we have developed a variety of TP probes for lipid rafts (5-8), lysosomes (9-11), mitochondria (11), pH (10,12), metal ions (Ca 2+ , Mg 2+ , Zn 2+ , Cu 2+ , Cu + , Na + , Hg 2+ , Ni 2+ ) (13,14), reactive oxygen species (ROS) (15,16), reactive nitrogen species (RNS) (17), thiols (18,19), hydrogen sulfide (20), and glucose (21,22), which meet all of the requirements mentioned above. In this mini review, we will briefly discuss the TP probes for lipid rafts, lysosomes, mitochondria, and pH that were developed in our laboratory, and their biomedical applications.…”