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Cited by 280

The DOI matches its Crossref record; 16 of the 16 references it cites were found in a registry or an index.

Nitrophenyl-EGTA, a photolabile chelator that selectively binds Ca2+ with high affinity and releases it rapidly upon photolysis.

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Ellis-Davies, G C, Kaplan, J H·1994·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.91.1.187
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Abstract

The synthesis and properties of a caged calcium are described. The compound is an ortho-nitrophenyl derivative of EGTA. It is synthesized in 10 steps and with 24% overall yield. The photosensitive chelator, nitrophenyl-EGTA, has a Kd value for Ca2+ of 80 nM and for Mg2+ of 9 mM. Upon exposure to UV radiation (approximately 350 nm), the chelator is cleaved, yielding iminodiacetic acid photoproducts with low Ca affinity (Kd = 1 mM). The quantum yield of photolysis of nitrophenyl-EGTA in the presence of Ca2+ is 0.23 and in the absence of Ca2+ is 0.20. In experiments with chemically skinned skeletal muscle fibers, a fully relaxed fiber equilibrated with nitrophenyl-EGTA-Ca2+ complex, in the presence of 1 mM free Mg2+, maximally contracted after a single flash from a frequency-doubled ruby laser (347 nm). Half-maximal tension was achieved in 18 ms at 15 degrees C. Nitrophenyl-EGTA provides a tool for the investigation of the mechanism of Ca(2+)-dependent physiological processes, since under conditions of normal intracellular Ca2+ and Mg2+ concentrations, only Ca2+ is bound by the photolabile chelator and on illumination released rapidly and in high photochemical yield.

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Metadata

Authors
Ellis-Davies, G. C., & Kaplan, J. H.
Venue
Proceedings of the National Academy of Sciences
Publisher
Proceedings of the National Academy of Sciences
Published
1994-01-04
Volume
91
Issue
1
Pages
187-191
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.91.1.187
OpenAlex
W2009248881
Cited by
280
References
16
FWCI
13.43
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: Nitrophenyl-EGTA, a photolabile chelator that selectively binds Ca2+ with high affinity and releases it rapidly upon photolysis. https://app.cochat.ai/papers/10.1073/pnas.91.1.187
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Ellis-Davies, G. C., & Kaplan, J. H. (1994). Nitrophenyl-EGTA, a photolabile chelator that selectively binds Ca2+ with high affinity and releases it rapidly upon photolysis. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.91.1.187

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

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