钙离子探针

BAPTA-AM 是一种钙离子螯合剂，具有细胞渗透性和选择性，可以阻断 hERG、hKv1.3 和 hKv1.5 通道 (IC50=1.3/1.45/1.23 μM)。BAPTA-AM对 Ca2+的亲和力是 Mg2+的 105 倍，可以用于钙在细胞信号传导中的作用。

BAPTA Tetrasodium is a selective fluorescent chelator for calcium. In conjunction with certain formazan dyes, BAPTA can be used in a colorimetric assay for Mg2+.

Fura PE-3 potassium是一种对Ca2+敏感的荧光团，可以装载在IPA (肺内动脉)和MA (肠系膜阻力动脉)中研究血管收缩。

Calcium Orange AM 是一种细胞内的钙指示剂。当游离钙与其结合时，会发出特异性荧光 (Ex/Em=549/576 nm)。Calcium Orange AM 不进入液泡，亦不会被分配到酸性小泡中。

Quin-2 is a high-affinity fluorescent calcium indicator (Kd = 115 nM for calcium). It displays high selectivity for calcium, as it is not affected by sodium gradients, membrane potential, or intracellular pH. High affinity probes like quin-2 are ideal for monitoring low levels of calcium, as are found in resting cells. Loadings of up to 2 mM quin-2 are without serious toxic effects, so quin-2 may be used to buffer intracellular calcium transients. Excitation/emission maxima for quin-2 are 339 and 492 nm, respectively.

Fura Red为荧光指示剂，其特性为随[Ca2+]浓度增加，荧光强度反比降低。

Fura-2 potassium salt 是一种常用的紫外光激发性荧光探针，可用于细胞内钙离子成像。

Fluo-4 AM是一种细胞可渗透的钙离子（Ca 2+）荧光指示剂/化学探针，适用于荧光成像、流式细胞分析和孔板筛选，激发波长为488nm左右，发射波长为512-520nm。

5-Nitro BAPTA tetramethyl ester是一种钙螯合剂，用于双光子探针合成，实现细胞内钙离子实时成像，可检测肝组织内100-300 μm深度的钙波，持续1100-4000 s，并可与2-Me取代TM荧光化合物结合，制成红色荧光探针。

5-Nitro BAPTA, a calcium chelator, combined with 2-Me-substituted TM (as a fluorescent moiety), forms a red fluorescent probe (CaTM-2 AM) for imaging cytoplasmic Ca 2+ in cultured living cells. It serves as a building block for synthesizing Ca 2+ specific chelators, Ca 2+ buffers, and fluorescent Ca 2+ indicators [1] [2].

Fluo-3FF is a fluorescent calcium indicator. It is a di-fluorinated analog of Fluo-3 that displays about a 100-fold lower affinity than Fluo-3 for calcium (Kds = 42 and 0.4 μM, respectively). Low affinity calcium indicators are particularly useful for studying compartments with high concentrations of calcium, such as endoplasmic reticulum, where high affinity dyes will be insensitive to luminal fluctuations. Fluo-3FF has excitation/emission maxima of approximately 506 and 526 nm, respectively.

Fura-FF AM is a cell-permeable acetoxymethyl ester of the fluorescence calcium indicator fura-FF (potassium salt) . As fura-FF AM enters cells, it is hydrolyzed by intracellular esterases to produce fura-FF. Fura-FF is a difluorinated derivative of the calcium indicator fura-2 . Unlike, fura-2, fura-FF has negligible magnesium sensitivity, thus reducing interference from this cation. Fura-FF also has a higher calcium dissociation constant than fura-2 (Kd(calcium) = 6 and 0.14 μM, respectively). However, the spectral properties of fura-FF and fura-2 are similar with fura-FF displaying excitation/emission spectra of 365/514 nm in the absence of calcium, with a shift to 339/507 nm in the presence of a high calcium concentration. Low affinity calcium dyes, including fura-FF, are preferred for studying compartments with high concentrations of calcium, such as mitochondria, or in cell systems that have relatively low calcium buffering capacities, such as neuronal dendrites and spines.

Hydroxy naphthol blue disodium 作为一种钙离子金属指示剂和碱土金属离子比色试剂(λmax = 650 nm)，在pH值介于12至13的环境中表现出明显的颜色变化；该指示剂在钙离子存在时显淡红色，在EDTA二钠作用下则转为深蓝色。

Indo-1 AM is an indicator of fluorescent Ca2+ (λex=340 nm, λem=405/485 nm).

Oxonol V是一种对测量细胞膜电位反应缓慢的敏感探针。

Rhod-5N is a low affinity fluorescent calcium probe (Kd = 320 μM). Low affinity calcium indicators are particularly useful for studying compartments with high concentrations of calcium, such as endoplasmic reticulum, where high affinity dyes will be insensitive to luminal fluctuations. Rhod-5N has excitation/emission maxima of approximately 551 and 576 nm, respectively

Calceincalcium potassium 是 Calcein 的钙钾盐形式。这种化合物是一种荧光染料和自灭探针，用于作为脂囊泡渗漏的指示剂，并可用于 EDTA 钙离子的滴定和作为荧光测定钙离子的络合指示剂。此外，Calceincalcium potassium 还可以作为模型药物，评估药物递送系统的效率和生物利用度。

Fura-FF pentapotassium salt 是一种低亲和力的钙荧光染料 (Ex/Em: 365/514 nm, 无钙; 339/507 nm, 高钙)。

Fura-2 AM是一种膜渗透的Ca2+(钙离子)指示剂，在细胞内被酯酶esterase转变为Fura-2。Fura-2 AM的荧光发射波长在510 nm左右，在高钙浓度和低钙浓度下分别显示出340和380nm的激发最大值，可以用荧光强度比计算钙离子浓度。

OG 488, SE（Oregon green 488 succinimidyl ester）是一种绿色荧光染料，在生理pH范围内（pH=6-8）对pH不敏感，可用于监测活细胞或微生物的增殖。