BCECF Acid,Cell Impermeant pH

核酸（nucleic acid）

端（有或无磷酸基）。书写核酸的一级结构时，习惯上从左到右，从5′到3′，碱基间的小横也可省略。 　　可用快速方法测定核酸的碱基序列。已有不少核酸的一级结构已确定。大的如烟草叶绿体DNA含155844个碱基对，小的如tRNA分子，平均含70多个核苷酸残基。核酸的多核苷酸链盘曲折叠成特定的空间结构。对DNA和tRNA的空间结构了解得较多。双链DNA在溶液中的结构基本符合著名的双螺旋模型。 　　性质和测定 核酸的分子量为几万到几百万或更多。可因高温、极端pH及某些化学试剂的影响

Measurement of Ion Fluxes and pH Gradients Across Cell Membranes

Movement of ions across cell membranes is associated with processes such as cell signaling, regulation of cell volume, maintenance of cell composition and pH, and energy transduction. Even in the erythrocyte, a very specialized cell

Simultaneous Analysis of Intracellular pH and Ca2+ from Cell Populations

. One of the fundamental problems in studying these ionic events is that changes in pHin modify Ca2+ regulatory mechanisms and changes in Ca2+ may modify pH regulation. It is desirable to use a technique that allows concomitant monitoring of these two ions in cell