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Updated: Feb 4, 2026

Testing Epithelial Permeability in Fetal Tissue-Derived Enteroids
Published on: June 16, 2022
Design and synthesis of cell-permeable fluorescent nitrilotriacetic acid derivatives
Genichiro Tsuji1, Takayuki Hattori1, Masashi Kato2
1National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-9501, Japan.
Abstract:
Fluorescence labeling of the target molecules using a small molecule-based probe is superior than a method using genetically expressed green fluorescence protein (GFP) in terms of convenience in its preparation and functionalization. Fluorophore-nitrilotriacetic acid (NTA) conjugates with several ester protecting groups were synthesized and evaluated for their cell membrane permeability by fluorescence microscopy analysis. One of the derivatives, acetoxymethyl (AM)-protected NTA conjugate is hydrolyzed, resulting in intracellular accumulation, thus providing localized fluorescence intensity in cells. This modification is expected as an effective method for converting a non-cell membrane permeable NTA-BODIPY conjugates to a cell membrane permeable derivatives.
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