RiboGreen RNA Reagent
目录号 : GC26545RiboGreen RNA Reagent 是一种超灵敏的荧光核酸染料,用于溶液内RNA的定量检测。
Sample solution is provided at 25 µL, 10mM.
1.概述
在RiboGreen的RNA定量检测中,为了获得完全的线性动力学范围,需要使用两个不同的染料浓度。在准备RiboGreen的工作液之前(见下试剂准备),需要先决定是希望测定高宽度实验(High-range assay)(20ng/mL-500ng/mL RNA),还是低宽度实验(Low-range assay)(1ng/mL-50ng/mL RNA),或两个范围都要检测。
2.试剂准备
实验当天,在无菌的一次性聚丙烯塑料管内制备RiboGreen的水溶性工作液。避免使用玻璃器皿,因RiboGreen可能粘附到玻璃表面。制备好的RiboGreen工作液需避光保存。最好在工作液配制后数小时内用完,不要长期保存待用。
3.准备RNA标准曲线
对于标准曲线,可以使用商业化的RNA Standard,比如:普遍使用的16S和23S核糖体RNA;或其它纯化的RNA制品。有的时候,推荐使用与待测定样本类似的RNA标准来建立标准曲线。一般来说,绝大多数单链的RNA分子能产生几乎等同的荧光信号。在核苷、盐、尿素、乙醇、氯仿、去污剂、蛋白质和琼脂糖这些常见的污染核酸试剂的化合物存在时,RiboGreen的检测结果仍可维持良好的线性关系,即便荧光强度可能会受到影响。为了确保达到有效的对照,用于制备标准曲线的RNA溶液应该与待测样本保持一致,这样能保证含接近相似水平的杂质化合物。
3.1在塑料瓶中用1xTE buffer配制浓度为2 μg/mLRNA溶液。用比色杯在1cm长度通路下测量该RNA溶液在260nm(A260)下的基本吸光值,A260=0.05相当于RN A浓度2 μg/mL。
3.2制作High-range标准曲线时,通过稀释2μg/mLRNA溶液配制一系列的2x终浓度RNA标准溶液至一次性无核酸酶的塑料管中,最后转移到比色皿或培养板中。
3.3制作Low-Range标准曲线时,通过稀释2μg/mLRNA溶液配制一系列的2x终浓度RNA标准溶液至一次性无核酸酶的塑料管中,最后转移到比色皿或培养板中。
3.4等体积混合RiboGreen试剂工作液(见2-试剂准备)和2xRNA标准溶液。于室温避光孵育2-5min,务必确保测量容器内加入了足够体积的测量液,对10x10mm比色皿来说,不能低于2mL;对96孔板的各孔来说,不要低于200μL。
3.5选择使用荧光光度计或荧光酶标仪来测定样本荧光值,选择标准的荧光素波长(激发~480nm,发射~520nm)。
3.6将每个样的荧光值减掉空白的荧光值。之后使用校正好的荧光值为纵坐标,RNA浓度为横坐标,来建立标准曲线。
4.样本分析
4.1用1xTE buffer稀释样品到合适体积(比如:1.0mL到10x10 mm比色杯或100μL到96孔微孔板)。最好每个待测样本做不只一个稀释倍数。
待测样本稀释倍数越高,越有助于降低特定污染物的干扰作用。然而,也要避免特别小的样本体积,因为难以准确测量。另外,同一个实验中,杂质水平尽量保持一致,要降低杂质引起的样品之间信号差异。例如,如果一系列RNA样品含盐浓度相差很大,那么它们就无法用一个简单的标准曲线来进行比较。为了避免这样的问题,如果可能,调整所有样品中杂质浓度到相同水平。(见5-样本中的DNA清除)
4.2每个样品中加入等体积的RiboGreen测量试剂(见2-试剂准备),于室温避光孵育2-5min。
4.3选择与标准曲线测定时相同的仪器参数来测定样本荧光值。为了降低光漂白效应,所有样本的荧光测定时间保持不变。
4.4将每个样的荧光值减掉空白的荧光值。根据已经产生的RNA标准曲线来确定样本的RNA浓度。
4.5可能的话,通过做不同的样本稀释再重复测定,来验证定量结果。
5.样本中的DNA清除
RiboGreen也可以结合DNA,可以先用无RNA酶的DNA酶来去除样本中的DNA,从而避免由于DNA和RiboGreen结合产生的荧光干扰,确保样品中的荧光全部来自R iboGreen和RNA的结合。
5.1准备10x DNase digestion buffer:无核酸酶的200mM Tris-HCl, pH 7.5,100 mM MgCl2,20 mM CaCl2。
5.2向每个含DNA样品中加0.11倍体积的10xDNase digestion buffer。(例如,如果样品为9mL,就加入1mL的10x buffer)。
5.3按照1 μg DNA添加~5 unit的无RNase的DNase l。
5.5 37°C孵育90min。
5.5用1xTE buffer至少10倍稀释样品以降低消化液中残留盐离子对RiboGreen测量产生干扰。
5.6按照上述步骤进行RiboGreen测定实验。
RiboGreen RNA Reagent is an ultra sensitive fluorescent nucleic acid dye used for quantitative detection of RNA in solution. The detection and quantification of trace RNA are particularly important in a large number of molecular biology experiments, including the determination of in vitro transcription RNA production, as well as the determination of RNA concentration before conducting Nor Thern Blot, S1 nuclease experiments, RNase protection experiments, cDNA library preparation, reverse transcription PCR, and differential display PCR.
The most common method for nucleic acid concentration determination is to measure the absorbance value at a wavelength of 260nm (A260). However, the main drawback of the absorbance based detection method is that proteins and free nucleotides have significant interference with the light signal; And the detection sensitivity is low (A260=0.1 is equivalent to 4 μ g/mL RNA in solution); The application of sensitive fluorescent nucleic acid dyes can avoid many problems caused by these factors.
RiboGreen can quantify RNA at concentrations as low as 1ng/mL and measure it using a fluorescence enzyme-linked immunosorbent assay (ELISA) reader, standard fluorescence spectrophotometer, or filter fluorometer. The maximum excitation wavelength of this probe after binding to RNA is around 500nm, and the maximum emission wavelength is around 525nm. Reading with a fluorescence enzyme-linked immunosorbent assay (ELISA) reader, a reaction system of 200 μ L can detect RNA as low as 200 pg, which is 200 times more sensitive than the fluorescence analysis method based on ethidium bromide and 1000 times more sensitive than the analysis method based on ultraviolet absorption peak. Using two dye concentrations, RiboGreen can measure RNA concentrations within a linear range of up to three orders of magnitude, ranging from 1ng/mL to 1 μ g/mL RNA. High range assay can quantify RNA ranging from 20ng/mL to 500ng/mL, while low range assay can quantify RNA ranging from 1ng/mL to 50ng/mL. Even in the presence of several common impurities in nucleic acid preparations (including nucleotides, salts, urea, ethanol, chloroform, surfactants, proteins, and agarose) in the system, this linear relationship can be maintained. In addition, RiboGreen can also bind to DNA by pre treating the mixed sample with DNase and then quantitatively analyzing RNA selectivity using RiboGreen.
Cas No. | SDF | ||
分子式 | 分子量 | ||
溶解度 | 储存条件 | Store at 4°C,protect from light | |
Shipping Condition | 评估样品解决方案:配备蓝冰进行发货。所有其他可用尺寸:配备RT,或根据请求配备蓝冰。 |