5-(and-6)-carboxy-2',7'-dichlorofluorescein is similar to carboxyfluorescein ( 51013)but has lower pK_a, It is useful for detecting pH in more acidic environment.

• pK_a = 4.8.
• l_ex\l_em = 504nm\529nm.
• e= 90,000.
• Orange solid soluble in DMSO and pH>6 buffers.
• Store at 4?C. Protect from light, especially in solution.
• C₂₁H₁₀Cl₂O₇.
• Mwt: 445.
• [111843-78-8]