5-(and-6)-carboxy-2',7'-dichlorofluorescein is similar to carboxyfluorescein, but has lower pK_a. It is useful for detecting pH in more acidic environment. Also see the membrane-permeant compound dichlorofluorescein diacetate.
<ul>
<li>pK_a = 4.8</li>
<li>&lamba;_Ex/&lamba;_Em = 504/529 nm</li>
<li>&epsilon;= 90,000</li>
<li>Orange solid soluble in DMSO and pH&gt;6 buffers</li>
<li>Store at room temperature and protect from light, especially in solution</li>
<li>C₂₁H₁₀Cl₂O₇</li>
<li>MW: 445</li>
<li>[111843-78-8]</li>
</ul>