Synthesis and in vitro evaluation of dioxopyrrolopyrroles as potential low‐affinity fluorescent Ca2+ indicators
Makaleler > Tam Makale · 2004
Yazarlar: Nesibe Avcıbaşi, Mario Smet, Bert Metten, Wim Dehaen, Frans C. De Schryver, Geert Bultynck, Geert Callewaert, Humbert De Smedt, Ludwig Missiaen, Noël Boens
International Journal of Photoenergy, Uluslararası, Wos, 2004, cilt 6, ss 159-167
DOI: 10.1155/s1110662x04000200
Özet
Three new low‐affinity fluorescent Ca2+ indicators excitable with visible light, namely 3‐phenyl‐6‐(4‐(3‐carboxymethoxy‐4‐(N,N‐dicarboxymethylamino)phenyl)phenyl)‐2,5‐dicarboxymethyl‐1,4‐ dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione (DPP1), 3‐phenyl‐6‐(5‐(3‐carboxymethoxy‐4‐(N,N‐dicarboxymethylamino) phenyl)thien‐2‐yl)‐2,5‐dicarboxymethyl‐1,4‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione (DPP2) and 3‐ (thien‐2‐yl)‐6‐(5‐(3‐carboxymethoxy‐4‐(N,N‐dicarboxymethylamino)phenyl)thien‐2‐yl)‐2,5‐dicarboxymethyl‐ 1,4‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione (DPP3) have been synthesized and evaluated for their Ca2+ binding properties via fluorimetric titrations. The in vitro dissociation constant Kd measured at 21 ∘C in 100 mM KCl buffered solution, pH 7.05, for the Ca2+ –DPP1 complex is 10 μM; for Ca2+ –DPP2 and Ca2+ –DPP3 a Kd value of 20 μM is found. All three indicators form 1: 1 complexes with Ca2+. The fluorescence quantum yields of the uncomplexed forms of DPP1, DPP2 and DPP3 are 1.2 × 10−2, 3.4 × 10−2 and 3.6 × 10−2, respectively. After binding to Ca2+ these values increase to 4.8 × 10−2, 5.0 × 10−2 and 5.1 × 10−2, respectively.