Search Thermo Fisher Scientific
我们总结了一系列要点和技巧并建立了一个详细的知识库,以满足您的各类科研需求,助您优化试验,获得最理想的结果。
请浏览下列相关问题:
人们通常使用260nm和280nm(A260/A280)的吸光度比值来衡量样本纯度。对于DNA而言,理想的比值为1.8,容许的范围在1.7-1.9之间。同时,A260/A230的比值也可用于检验样品是否存在其他物质的污染。DNA分子的理想比值范围在1.8-2.0。DNA的纯度也可通过琼脂糖凝胶电泳来检验。例如对于基因组DNA而言,需要观察长片段的平均大小。
在此推荐我们的ChargeSwitch技术,这种DNA纯化技术针对微量或降解样本有很高的灵敏度。
请浏览此网页,该网页介绍了从血液中分离基因组DNA的各种试剂盒的特点。
是的,我们提供ChargeSwitch 法医DNA纯化试剂盒。请点击 此处了解更多关于DNA提取的信息。
根据起始样品量和纯化方式的不同,我们专门设计了几种针对植物DNA提取的试剂盒。请点击此 链接了解我们目前供应的各种植物DNA提取试剂盒的特点。
我们推荐使用我们的PureLink基因组DNA小提试剂盒或ChargeSwitch 细菌基因组DNA小提试剂盒(货号CS11301),两款试剂盒均能够用于提取革兰氏阳性和革兰氏阴性的细菌样本。这种简易的单管操作方案无需离心或过滤步骤。请点击此处了解更多关于细菌DNA提取的信息。
我们推荐使用ChargeSwitch 口腔细胞基因组DNA试剂盒,这款产品专用于从口腔细胞样本中分离高品质的基因组DNA。同时我们也提供标准化试剂盒(normalized kits),确保用户针对不同样品分离所得的DNA浓度进行标准化处理。
我们为此提供了三种试剂盒:用于FFPE组织的RecoverAll™总核酸分离试剂盒,MagMAX™ FFPE总核酸分离试剂盒和MagMAX™ FFPE DNA分离试剂盒。请点击此处详细了解三种试剂盒的各自特点及差异。
许多因素都可能影响从FFPE组织提取的DNA的总体质量和得率。以下为我们就如何解决这些关键影响因素而提出的一些建议:
请点击此处阅读更多关于FFPE样本核酸提取的信息。
此处提供了一份用于DNA/RNA纯化的单独供应的缓冲液列表。
Yes. However, the yield from frozen blood is significantly lower than the yield from fresh blood.
The JetQuick Blood and Cell Culture DNA Maxiprep Kit can be used for blood samples >10 ml. The manual offers a protocol for the concentration of the sample first.
No. The JetQuick Blood and Cell Culture DNA Midiprep Kit and Maxiprep Kit are not validated for tissue samples.
Yes. However, the yield from frozen blood is significantly lower than the yield from fresh blood.
苯酚相和中间相可于4°C条件下过夜储存。样本也可在清洗液(用10%的酒精配置的0.1 M柠檬酸钠)中储存至少几个小时。也可将样本重悬于75%的乙醇中,在4°C条件下储存数月。
可以,单链DNA将在DNA相中分离。
DNAzol试剂可以用于组织、细胞或血液的DNA提取。DNAzol是一款包含了胍盐去垢剂的裂解液,能够选择性地沉淀细胞裂解液中的DNA。使用1 mL DNAzol试剂能够从50 mg组织或1x107至3x107个细胞中分离基因组DNA。DNAzol BD试剂专用于分离血液基因组DNA。使用1 mLDNAzol BD试剂能够从0.5 mL全血中分离基因组DNA。植物DNAzol试剂专用于分离植物基因组DNA。使用0.3 mL植物DNAzol试剂能够从0.1 g植物组织中分离基因组DNA。
我们推荐将DNAzol试剂储存于室温(一年之内可保持稳定),也可以将其储存于4°C。在37°C条件下储存1周并未显示不良效应。DNAzol的裂解物(匀浆)可于15–30°C下储存1个月;在4°C或–20°C条件下储存10个月之后,DNAzol裂解物(匀浆)中仍能够提取得到高分子量的、可被限制性内切酶完全酶切的基因组DNA,且DNA在PCR反应中也可以得到较好的结果。在漂洗阶段,DNA可以保存于95%的乙醇中,在15°C至30°C至少储存一周,或4°C左右条件下至少储存三个月。DNA保存于DNAzol试剂中,可于室温下储存一个月,或4°C下储存十个月。
如需降低/去除样本中的RNA量,请使用1 µg/mL RNase A处理基因组DNA。
无需进行胰酶消化。直接在10 cm2的培养皿中加入1 mL DNAzol试剂。前后摇晃平板,使DNAzol均匀覆盖培养皿。将裂解产物吸入离心管中,加入酒精用于沉淀基因组DNA。如果您希望用胰酶消化以便对细胞进行计数,请于胰酶消化之后离心得到用于DNA分离的细胞沉淀。完全吸去上清液后,向细胞沉淀中加入DNAzol试剂。吹打细胞3–4次以使其彻底裂解,然后进行离心。
使用DNAzol试剂分离得到的实际上是总DNA,所以质粒DNA也会和基因组DNA一并分离出来。线粒体基因组与质粒类似,也可通过DNAzol试剂分离出来。可将离心步骤之前的乙醇室温孵育步骤从1分钟延长至5-10分钟,以获得最大的DNA得率。
GeneCatcherTM技术利用磁珠分离基因组DNA。它专用于从人类血液中提取基因组DNA,无需离心步骤。GeneCatcherTM试剂盒还专门进行了设计和优化,可使用自动化液体处理平台Tecan Freedom EVO从血液中分离基因组DNA。请点击此处浏览完整的工作流程。
是的,该试剂盒兼容EDTA、柠檬酸和肝素。在使用GeneCatcherTM血液gDNA试剂盒时,尽管不会影响其纯化效果,但我们并不建议采用肝素作为抗凝剂,因为痕量级的肝素都可能成为强效的PCR抑制剂。
可以。处理全血白细胞层时,可使用与获得此白细胞层样本的全血相同体积的试剂来处理样本。如果原始血液样本的体积超过10 mL,可能需要将样本分成多等份来处理。
纯化的片段大小介于100 bp与12 kb之间。我们的试剂盒附带两款缓冲液,结合缓冲液(B2)与结合缓冲液HC(B3)。结合缓冲液HC(B3)能够去除引物二聚体和小于300bp的扩增失败的短PCR产物。
与原试剂盒相比,微量试剂盒使用了相同的缓冲液(HC缓冲液除外),不同的纯化柱(微量)。试剂盒套装中包含了相同的离心柱,但多了一种用于凝胶中DNA提取的缓冲液,溶胶液(Gel Solubilization Buffer,L3)。
纯化的片段大小应介于100 bp与12 kb之间。
PureLink PCR纯化试剂盒与PureLink 凝胶纯化试剂盒两者间的缓冲液和操作步骤均不同。因此,您可以换用离心柱,但须注意使用正确的缓冲液和实验方案。
是的,您可以使用我们的试剂盒来纯化限制性内切酶酶切后的质粒DNA。
是的,您可以使用PureLink PCR快速纯化试剂盒从液体样本中纯化任何100bp至12kb的双链DNA。超螺旋DNA也能够被纯化,只是可能会出现一些切口。
PureLink试剂盒基于离心柱形式,而ChargeSwitch试剂盒基于磁珠技术。在低pH条件下,磁珠带有正电从而能够结合带负电的核酸。
有的,请参见 此 页面,来比较ChargeSwitch-Pro PCR纯化试剂盒与QIAquick PCR纯化试剂盒两者所纯化的扩增子的测序结果。
抱歉,我们不单独销售结晶紫。不过,TOPO XL试剂盒以及S.N.A.P.TM非紫外照射型凝胶纯化试剂盒(货号K200025)中均包含了本品。
可以,我们的凝胶提取试剂盒和TAE及TBE琼脂糖凝胶均兼容。
40bp至10kb范围内的DNA片段均可通过PureLink 快速凝胶提取试剂盒进行纯化。不过,小于80bp的片段的回收率可能会降低50%乃至更多。对于单链DNA与RNA,下限为200nt。
可以,用水洗脱是可以的,不过请确保水质洁净,pH介于7.5和8.5之间。
常规和低熔点琼脂糖凝胶均适用。当凝胶浓度超过2%时,每100 mg 胶使用600 μL溶胶液进行溶解。
Yes, the PureLink Microbiome DNA Purification Kit has been successfully used for isolation of microbial DNA from human, mouse, rat, horse, cow, dog, cat, and other types of stool/feces. Despite the fact that these samples are very different in terms of consistency, presence of miscellaneous food debris, composition of the microbial community, various inhibitors present, and other variables, the kit enabled fast and efficient isolation of substantial amounts of highly clean microbial DNA.
If fresh stool, body fluids, swabs, and other samples cannot be processed, freezing the samples at -20 degrees C or -80 degrees C is the best way to preserve them. We recommend keeping freeze/thaw cycles to a minimum. For many samples, storage at 4 degrees C for up to one week is also fine. Please note, use of commercially available DNA stabilizing reagents can negatively impact the downstream nucleic acid isolation, or make the workflow more challenging or lengthy.
We simplified the protocol for those scientists who are only interested in human DNA isolation from stool, as mammalian cells are easy to lyse and DNA isolation can be performed faster. Microbes have thicker cell membranes of a different composition, and are generally more difficult to lyse. Thus, separate protocols, with additional steps to ensure efficient disruption for isolation of microbial DNA, were developed.
Yes, when using microbial DNA protocol with PureLink Microbiome DNA Purification Kit, you will get both host and microbial DNA. The bulk of DNA in human stool is of microbial origin. Depending on the sample, we roughly estimate that approximately 10-20% of the total DNA isolated is host DNA while the remaining 80-90% is microbial DNA.
The PureLink Microbiome DNA Purification Kit was developed to be used with a wide range of sample types including stool, soil, urine, saliva, swabs, and other samples. In addition to testing bacterial samples, we have also tested fungi samples. Specialized beads in the kit efficiently break open cell walls and membranes with the help of heat and chemical lysis. This triple lysis approach works great for tough-to-lyse species such as fungi. Additionally, the stool-derived inhibitors are rapidly eliminated with a novel clean up buffer, resulting in DNA that is compatible with any type of downstream analysis.
Yes, the PureLink Microbiome DNA Purification Kit works for swabs samples. However this kit does not come with swabs. You will find some suggested swab part numbers that we have tested with this kit in swab protocol on the product page.
We tested 3 liquid versions of transport media: Amies, Stuart, and Cary Blair, with all three being compatible with the PureLink Microbiome DNA Purification kit.
For highly pure samples, both fluorometers (such as the Qubit Flourometric Fluorometer) and spectrophotometers (such as NanoDrop One Spectrophotometer) are successfully utilized and give very similar readings. However, when dealing with DNA or RNA samples that have high levels of contaminants, such as salts or protein, the Qubit Fluorometer provides a more accurate reading, as this instrument uses dyes that are very specific to the analyte of interest. We have seen some challenging microbiome and FFPE samples where the Qubit Fluorometer readings were up to 2 times lower compared to the NanoDrop spectrophotometer, which is overestimating DNA concentrations. More and more laboratories are use both instruments side by side, as they provide complimentary information: the Qubit fluorometer is more accurate and specific in terms of determining nucleic acid concentration, while the NanoDrop spectrophotometer provides a valuable information regarding the purity (ie., A260/280, A260/230).
For Research Use Only. Not for use in diagnostic procedures.