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View additional product information for Qubit™ 4 Fluorometer - FAQs (Q33226)
75 product FAQs found
分光光度计不能区分完整核酸、小片段、降解样本，以及单核苷酸。试剂盒中的染料仅检测长度超过20mer左右的完整核酸链。试剂盒仅识别完整DNA或RNA，而忽略降解样本。
请从我们的网站下载并安装最新版本的Qubit固件（https://www.thermofisher.com/us/en/home/industrial/spectroscopy-elemental-isotope-analysis/molecular-spectroscopy/fluorometers/qubit/qubit-technical-resources.html）
对Qubit 1.0, 2.0 和 3.0荧光计，去这个链接下载：https://www.thermofisher.com/us/en/home/industrial/spectroscopy-elemental-isotope-analysis/molecular-spectroscopy/fluorometers/qubit/qubit-technical-resources/previous-qubit-models.html
对于Qubit 1.0仪器，如果它和电脑相联，那么将它和电脑的连接解除，拔掉电源，等待至少10秒，然后重新插上电源。
对于Qubit 2.0，3.0，4.0 仪器，如果可能，关闭电源或拔掉电源，等待至少10秒，然后重新插上电源。在固件升级过程中，请不要将仪器电源拔掉或将USB闪存拔掉。
如果可能，你可以试试使用较大体积的样本（最多20µL）。此外，如果你使用的是Qubit DNA BR检测试剂盒或Qubit RNA BR检测试剂盒，可以试试Qubit DNA HS检测试剂盒或Qubit RNA HS检测试剂盒，因为它们的灵敏度更高。
稀释你的样本，或者使用较小体积的样本，重新检测。此外，如果你使用的是Qubit DNA HS检测试剂盒或Qubit RNA HS检测试剂盒，可以试试Qubit DNA BR检测试剂盒或Qubit RNA BR检测试剂盒，因为它们的灵敏度更低。
如果出现这种情况，在“查看标准品”或"查看校准"下查看标准品和样本的原始荧光值。确认样本的荧光值落在标准品的荧光值之间（或稍稍高于最高的标准品）。如果不是，那么样本已经超过了检测的精确范围。Qubit荧光计的屏幕会显示“超出检测范围”。
这条信息出现可能有几个原因。请在您的仪器上检查如下事项：
1.在 “查看标准品”或"查看校准"下查看标准品的原始荧光值。Standard 2的荧光值是否至少是Standard 1荧光值的10到50倍。对于蛋白检测，Standard 3的荧光值是否是Standard 2荧光值的大约2倍。
2.检查你的标准品放置顺序是否正确。
3.检查你是在合适的检测管中使用了10µL的标准品和190µL的Qubit染料工作溶液。
4.对于RNA检测，可以试试新开一管Standard 2，以防已经打开的RNA标准品已经降解。
5.检查Qubit检测试剂盒以及标准品的收货日期。试剂盒从收到的日期起可以稳定使用至少6个月。如果该试剂盒已经超过一年并且Qubit荧光计不能读取标准品，那么应当换用一个新的试剂盒。
6.检查仪器是否正常工作。打开盖子。运行任一Assay的新的校准。你可以看到一个红色灯（对于RNA Assay）或一个蓝色灯（对于所有其它Assay）闪烁5次。
可以，使用手册中有关于此应用的说明。
是的。我们观察到20–30%的差别。对于不同形态的质粒DNA，我们建议使用和样本中的质粒DNA形态非常近似的标准品。欲获知创建自定义优化检测法的信息，请访问我们的网站(https://www.thermofisher.com/search/results?query=MyQubit)。
是的。对于典型的高浓度的小抽DNA（超过50 ng/μL），可以使用Qubit DNA BR检测法。对于微量质粒或少量质粒，可以使用Qubit DNA HS检测法。但是，关于构象问题请参见下一问题。
Qubit 2.0荧光计原装的USB为2GB，Qubit 3.0和4.0荧光计原装的USB为4GB。
我们将为您更换该设备。请联系我们的技术支持部门以了解详情，邮件地址LifeScience-CNTS@thermofisher.com。
不能。如果设备被拆解或者你试图修理设备则设备的保修将失效。最好电话或邮件通知我们的技术支持团队以获取帮助。
Qubit 荧光计内有两个光源——均为LED灯。它们预期的使用寿命至少是5年。
如果使用和样本一样的工作溶液，那么稀释后的标准品最多可以使用3小时。在缓冲液中稀释的Qubit试剂稳定长达3小时。如果存在，蒸发会导致染料和样品浓度更高，这将影响结果。
Invitrogen Qubit 3.0和4.0荧光计可以在一个.csv文件中存储最多相当于1000个样本的数据。
Qubit 2.0荧光计可以在一个.csv文件中存储最多200行数据。
最早的Qubit (1.0)荧光计可以在一个.csv文件中存储最多20行数据。
是的。这些试剂盒适用于所有Qubit荧光计。
是的，Qubit 4.0荧光计带有一个USB闪存盘和USB数据线，用于和电脑相连。
是的。
Qubit荧光计能够非常准确、灵敏并简便的对DNA, RNA和蛋白质进行定量。它是为分子生物学实验室设计的，用于处理稀有或难以处理的珍贵样品，以及需要精确测量的应用，如实时PCR。查看关于Qubit荧光计的更多信息(http://www.thermofisher.com/us/en/home/life-science/laboratory-instruments/fluorometers/qubit/qubit-fluorometer.html.html)
Absorbance readers cannot distinguish small fragments, degraded samples, or single nucleotides from intact nucleic acid. The dyes in the kits only detect intact strands longer than about a 20-mer. The kits are only recognizing intact DNA or RNA, and ignoring degraded sample.
Please download and install the most current version of the Qubit Firmware from our website: https://www.thermofisher.com/us/en/home/industrial/spectroscopy-elemental-isotope-analysis/molecular-spectroscopy/fluorometers/qubit/qubit-technical-resources.html
For Qubit Fluorometers 1.0, 2.0 and 3.0 go to this web link: https://www.thermofisher.com/us/en/home/industrial/spectroscopy-elemental-isotope-analysis/molecular-spectroscopy/fluorometers/qubit/qubit-technical-resources/previous-qubit-models.html
For the Qubit 1.0 instrument, if it is connected to a computer, disconnect it from the computer, unplug it, wait at least 10 seconds, then plug it back in.
For the Qubit 2.0, 3.0 and 4.0 instruments, power off or unplug the instrument if possible, wait at least 10 seconds, then plug it back in. Do not unplug the instrument or remove the USB stick during a firmware update.
You can try to use a larger amount of sample if possible (up to 20 µL). Alternatively, if you are using the Qubit DNA BR Assay or Qubit RNA BR Assay, try using the Qubit DNA HS Assay or Qubit RNA HS Assay, as these have higher sensitivity.
Dilute your sample, or use a smaller volume of sample in the assay and try again. Alternatively, if you are using the Qubit DNA HS Assay or the Qubit RNA HS Assay, try using the Qubit DNA BR Assay or Qubit RNA BR Assay, as these have lower sensitivity.
If this occurs, view the raw fluorescence values for the standards and samples under “Check Standards” or “Check Calibration”. Confirm that the values for the samples fall between the values of the standards (or a little above the highest standard). If they do not, the sample is out of the accurate range of the assay. The Qubit Fluorometer screen should indicate OUT OF RANGE.
There are several reasons why this message may appear. Please check the following on your instrument:
1.View the raw fluorescence value for the standards under “Check Standards” or “Check Calibration”. Make sure that the value of Standard 2 is at least 10- to 50-fold higher than the value of Standard 1. For the protein assay, make sure that the value of Standard 3 is about twice the value of Standard 2.
2.Check to see that you have used the tubes in the correct order.
3.Check to see that you used 10 µL of the standard and 190 µL of the Qubit dye working solution in the appropriate tubes.
4.For RNA assays, try an unopened tube of Standard 2 in case the open RNA standard tube has degraded.
5.Check the age of the Qubit assay kit and standards. Kits are stable for at least 6 months from the date of receipt. If the kit is older than a year and the Qubit Fluorometer will not read the standards, it may need to be replaced with a new kit.
6.Check to see if the instrument is working properly. Lift the lid. Run a new calibration for any assay. You should see a red light (for RNA assays) or a blue light (for all other assays) flash 5 times.
Yes, the manual has directions for this application.
Yes. We have seen a 20-30% difference. For the different forms of plasmid DNA, we recommend using a standard that more closely represents the composition of the plasmid DNA in the sample. For information on creating custom optimized assays, please visit our website (http://www.thermofisher.com/search/global/searchAction.action?query=MyQubit&resultPage=1&resultsPerPage=15&autocomplete).
Yes. Use the Qubit DNA BR Assay for a typical plasmid miniprep with a high concentration of DNA (over 50 ng/µL). Use the Qubit DNA HS Assay for plasmid rescue or methods that yield only small amounts of DNA. However, see the next question for conformation issues.
No, this assay is only compatible with Qubit 4 Fluorometer (Cat. No. Q33226) and Qubit Flex Fluorometer (Cat. No. Q33327).
Find additional tips, troubleshooting help, and resources within our Nucleic Acid Quantification Support Center.
Detection of somatic variants with the Oncomine Myeloid Research Assay GX has been verified down to 5% allele frequency.
Here is a list of kits that are compatible with Oncomine Myeloid Research Assay GX:
Nucleic acid isolation - RNA samples
- MagMAX mirVana Total RNA Isolation Kit, Cat. No. A27828
- PureLink Total RNA Blood Kit, Cat. No. K156001
- RNaseZap RNase Decontamination Solution, Cat. No. AM9780, AM9782, AM9784
Nucleic acid isolation - DNA samples
- MagMAX DNA Multi-Sample Ultra 2.0 Kit, Cat. No. A36570
- PureLink Genomic DNA Mini Kit, Cat. No. K1820-01
The recommended minimum sample input is 27.75 ng of DNA (1.11 ng/µL minimum concentration) and 14.25 ng of RNA (0.95 ng/µL minimum concentration).
The recommended controls are:
DNA Controls:
- Seraseq® Myeloid Mutation DNA Mix, Cat. No. 0710-0408 (SeraCare®)
- Myeloid DNA Reference Standard, Cat. No. HD829 (Horizon™)
- AcroMetrix™ Oncology Hotspot Control, Cat. No. 969056
RNA Controls:
- Universal Human Reference RNA, Cat. No. 740000 (Agilent™)
- Seraseq® Myeloid Fusion RNA Mix, Cat. No. 0710-0407 (SeraCare®)
Multiplex sequencing of up to 8 Oncomine Myeloid Research Assay GX samples (8 DNA+ 8 RNA) per lane on a GX5 Chip can be performed in a single run. There are 4 lanes on the GX5 Chip, so 32 total samples (32 DNA+ 32 RNA) can be run on one GX5 Chip (8 samples per run).
The Oncomine Myeloid Research Assay GX (Cat. No. A47857) includes the 2-pool DNA panel, the 1-pool RNA panel, Genexus Strip 1, and Genexus Strip 2-AS. The DNA panel is provided in two packs of 8 tubes (4 tubes of Myeloid DNA Pool 1 and 4 tubes of Myeloid DNA Pool 2 per pack). The RNA panel is provided in one pack of 8 tubes (Myeloid RNA Pool 1). Each primer pool in the panel is provided in pairs of tubes, where each tube pair contains one tube with primers in position 1 and one empty uncapped tube in position 2. Three 8-strip packs of the Genexus Strip 1 and Genexus Strip 2-AS (24 total of each strip) are provided with each kit.
The contents of each Oncomine Myeloid Research Assay GX kit are sufficient for up to 32 samples (32 x 3‑pool reactions: 32 x 2‑pool DNA reactions and 32 x 1‑pool RNA reactions).
The Oncomine Myeloid Research Assay GX includes 3 pools of Ion AmpliSeq oligonucleotide primers (a 2-pool DNA panel and a 1-pool RNA panel).
The Oncomine Myeloid Research Assay GX targets key genes and fusions associated with major myeloid disorders, including acute myeloid leukemia (AML), myeloid dysplastic syndrome (MDS), myeloproliferative neoplasms (MPN), chronic myeloid leukemia (CML), chronic myelomonocytic leukemia (CMML), and juvenile myelomonocytic leukemia (JMML). The DNA panel comprises 40 key genes while the RNA panel includes a broad fusion panel of 29 driver genes, enabling detection over 600 unique fusion isotypes. See flyer for gene targets (https://assets.thermofisher.com/TFS-Assets/CSD/Flyers/Oncomine_myeloid_assay_gx_flyer.pdf).
The Oncomine Myeloid Research Assay GX is a comprehensive targeted next-generation sequencing (NGS) assay designed for sensitive detection of myeloid disorder-associated DNA mutations and fusion transcripts in blood and bone marrow samples.
You can test the tolerance of the assay for your specific buffer formulation. For in-house generated compatibility information, substances were considered compatible at the indicated concentration in the Standard Test Tube Protocol (found in the manual for each protein assay) if the error in protein concentration estimation caused by the presence of the substance was less than or equal to 10%. The substances were tested using WR prepared immediately before each experiment. Blank-corrected 562nm absorbance measurements (for a 1000µg/mL BSA standard + substance) were compared to the net 562nm measurements of the same standard prepared in 0.9% saline.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
It is possible to have a substance additive affect such that even though a single component is present at a concentration below its listed compatibility, a sample buffer containing a combination of substances could interfere with the assay. You should take steps to eliminate or minimize the effects of the interfering substance(s) by diluting or removing the substance.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Refer to the information in the product-specific instruction booklet or our Tech Tip: Protein Quantitation Assay Compatibility Table (https://assets.thermofisher.com/TFS-Assets/LSG/Application-Notes/TR0068-Protein-assay-compatibility.pdf).
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Often, an alternative wavelength can be used, although the slope of the standard curve and the overall assay sensitivity will most likely be reduced. Our Tech Tip (https://tools.thermofisher.com/content/sfs/brochures/TR0025-Protein-assay-spectra.pdf) offers additional information on determining acceptable wavelengths for measuring protein assays.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Several factors affect protein assay accuracy and precision:
Replicates: The only way to evaluate the extent of random error is to include replicates of each standard and test sample. Because all test samples are evaluated by comparison to the standard curve, it is especially important to run the standards in at least triplicate. The standard deviation (SD) and coefficient of variation (CV) can then be calculated, providing a degree of confidence in your pipetting precision. If replicates are used, curve-fitting is done with the average values (minus obvious outliers).
Blank correction: It is common practice to subtract the absorbance of the zero assay standard(s) from the all other sample absorbance values. However, if replicate zero-assay standards will be used to calculate error statistics, then another independent value may be required for blank-correction. If the standards were prepared in a buffer to match that of the test samples, and this buffer contains components that may interfere with the assay chemistry, it is informative to blank the absorbances with a "water reference" (i.e., a zero-protein, water sample). Differences between the water reference and zero standard sample are then indicative of buffer effects.
Standard curve slope: The standard curve slope is directly related to assay accuracy and sensitivity. All else being equal, the steepest part of the curve is the most reliable. For most protein assays, the standard curve is steepest (i.e., has the greatest positive slope) in the bottom half of the assay range. In fact, the upper limit of an assay range is determined by the point at which the slope approaches zero; the line there is so flat that even a tiny difference in measured absorbance translates to a large difference in calculated concentration.
Measurement wavelength: The measurement wavelengths that are recommended for each protein assay method are optimal because they yield standard curves with maximal slope. This usually, but not always, corresponds to the absorbance maximum. (In certain circumstances, other considerations are also important in choosing the best possible measurement wavelength, such as avoiding interference from sample components that absorb at similar wavelengths). In fact, for most protein assays, depending on the precision required, acceptable results can be obtained using any measurement wavelengths within a certain range.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
One situation in which the dilution factor is important to consider is when the original sample has been pre-diluted relative to the standard sample. Suppose the original protein sample is actually known to be approximately 5 mg/mL. This is too concentrated to be assayed by the Pierce Bradford Plus Protein Assay Kit, for example, whose assay range in the standard microplate protocol is 100-1500 µg/mL. However, you could dilute it 5-fold in buffer (i.e., 1 part sample plus 4 parts buffer) and then use that diluted sample as the test sample in the protein assay. If the test sample produces the same absorbance as the 1000 µg/mL standard sample, then you can conclude that the test (5-fold diluted) sample is 1000 µg/mL, and therefore the original (undiluted) sample is 5 x 1000 µg/mL = 5000 µg/mL = 5 mg/mL.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
No. It is neither necessary nor helpful to know the protein concentration as it exists when the samples are diluted in assay reagent. The protein concentration when diluted by assay reagent is almost certainly not the value of interest; instead, one wants to know the protein concentration of the original test sample.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
No. Contrary to what many people assume, it is neither necessary nor even helpful to know the actual amount (e.g., micrograms) of protein applied to each well or cuvette of the assay. The amount of protein per well is almost certainly not the value of interest; instead, one usually wants to know the protein concentration of the original test sample.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Enter the concentration values for the standards in Column A and their corresponding absorbance data in Column B. Highlight both columns and from the Insert menu select Chart and XY (Scatter). Click on the resulting graph and select Add Trendline from the Chart menu. While viewing the graph next to the open Format Trendline window, choose Polynomial and set the Order to 2, 3 or 4 until the best-fit appears. Check the box near the bottom called Display Equation on Chart; then close the Format Trendline window. Use the resulting equation to determine protein concentration (y) of an unknown sample by inserting the sample’s absorbance value (x).
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Most modern plate readers and spectrophotometers have associated software that automatically plots a linear or curvilinear regression line through the standard points, interpolates the test samples on that regression line, and reports the calculated value. However, there are different methods for making the calculations “by hand”. You can find a detailed explanation and example in our Tech Tip.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
With most protein assays, sample protein concentrations are determined by comparing their assay responses to that of a dilution-series of standards whose concentrations are known. The responses of the standards are used to plot or calculate a standard curve. Absorbance values of unknown samples are then interpolated onto the plot or formula for the standard curve to determine their concentrations. The most accurate results are possible only when unknown and standard samples are treated identically. This includes assaying them at the same time and in the same buffer conditions, if possible. Because different pipetting steps are involved, replicates are necessary if you wish to calculate statistics (e.g., standard deviation, coefficient of variation) to account for random error. It is imperative to run a new standard curve for each set of samples to be tested
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Simply multiply the calculated concentration of the diluted sample by the dilution factor. For example: A protein sample is known to be approximately 5 mg/mL. This is too concentrated to be assayed by the Pierce Bradford Plus Protein Assay Kit, whose assay range in the standard microplate protocol is 100-1500 µg/mL. However, you could dilute it 5-fold in buffer (i.e., 1 part sample plus 4 parts buffer) and then use that diluted sample as the test sample in the protein assay. If the test sample produces the same absorbance as the 1000 µg/mL standard sample, then you can conclude that the test (5-fold diluted) sample is 1000 µg/mL, and therefore the original (undiluted) sample is 5 × 1000 µg/mL = 5000 µg/mL = 5 mg/mL.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
The unit of measure used to express the standards is by definition the same unit of measure associated with the calculated value for the unknown sample (i.e., final results for unknown samples will be expressed in the same unit of measure as was used for the standards). For example, if the standard concentrations are expressed as micrograms per milliliter, then the concentrations for the unknown samples, which are determined by comparison to the standard curve, are also expressed as micrograms per milliliter.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Protein standards should preferably be diluted using the same diluent as the sample(s). Sample assay responses are directly comparable to each other if they are processed in exactly the same manner. Variance in protein quantity is the only possible cause for differences in final absorbance (color intensity) if samples are dissolved in the same buffer and the same stock solution of assay reagent is used for all samples.
However, if only a “rough” estimate of protein concentration is needed, a blank-only correction can be used. In this case, a blank is prepared in the diluent of the sample to correct for its raw absorbance. The concentration of the sample is then determined from a standard curve obtained from a series of dilutions of the protein of known concentration prepared in water or saline solution.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Protein concentrations are generally determined and reported with reference to standards of a common protein, such as bovine serum albumin (BSA). If precise quantitation of an unknown protein is required, it is advisable to select a protein standard that is similar in quality to the unknown; for example, a bovine gamma globulin (BGG) standard may be used when assaying immunoglobulin samples.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Because proteins differ in their amino acid compositions, each one responds somewhat differently in each type of protein assay. Therefore, the best choice for a reference standard is a purified, known concentration of the most abundant protein in the samples. This is usually not possible to achieve, and it is seldom convenient or necessary. If a highly purified version of the protein of interest is not available or it is too expensive to use as the standard, the alternative is to choose a protein that will produce a very similar color response curve in the selected protein assay method and is readily available to any laboratory at any time. Generally, bovine serum albumin (BSA) works well as a protein standard because it is widely available in high purity and relatively inexpensive. Alternatively, bovine gamma globulin (BGG) is a good standard when determining the concentration of antibodies because BGG produces a color response curve that is very similar to that of immunoglobulin G (IgG).
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Pierce Bradford Protein Assay Kit and Pierce Bradford Plus Protein Assay Kit are variations on the use of Coomassie G-250 dye as a colorimetric reagent for the detection and quantitation of total protein first reported by Bradford in 1976. The Thermo Scientific 660 nm Protein Assay is a dye-based reagent that offers the same convenience as Coomassie-based assays while overcoming several of their disadvantages. In particular, the 660 nm Assay is compatible with most detergents and produces a more linear response curve (the detailed assay chemistry is proprietary). Our fluorometric protein assays are also based on dye binding chemistries.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Each protein in a sample responds uniquely in a given protein assay, and this protein-to-protein variation is observed as differences in the amount of color (absorbance) obtained when the same mass of various proteins is assayed concurrently by the same method. These differences in color response relate to differences in amino acid sequence, isoelectric point (pI), secondary structure, and the presence of certain side chains or prosthetic groups.
Depending on the sample type and purpose for performing an assay, protein-to-protein variation is an important consideration in selecting a protein assay method and in selecting an appropriate assay standard (e.g., BSA vs. BGG). Protein assay methods based on similar chemistry have similar protein-to-protein variation.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Before the sample is analyzed, it must be solubilized in a buffered aqueous solution. Depending on the source material and the procedures involved before performing the protein assay, the sample will likely contain a variety of non-protein components. Awareness of these components is critical for choosing an appropriate assay method and evaluating the cause of anomalous results. Every type of protein assay is adversely affected by substances of one sort or another. Components of a protein solution are considered interfering substances in a protein assay if they artificially suppress the response, enhance the response, or cause elevated background by an arbitrarily chosen degree (e.g., 10% compared to control). Additional components can include reducing agents, chelators, crowding agents, and protease inhibitors.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
There are several criteria that should be considered, including compatibility with the sample type and components, assay range and required sample volume, protein-to-protein uniformity, speed and convenience for the number of samples to be tested, and the availability of spectrophotometer or plate reader necessary to measure the color produced (absorbance) by the assay.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Unfortunately, no protein assay method exists that is either perfectly specific to proteins (i.e., not affected by any nonprotein components) or uniformly sensitive to all protein types (i.e., not affected by differences in protein composition). Therefore, successful use of protein assays involves selecting the method that is most compatible with the samples to be analyzed, choosing an appropriate assay standard, and understanding and controlling the particular assumptions and limitations that remain. The objective is to select a method that requires the least manipulation or pre-treatment of the samples to accommodate substances that interfere with the assay. Each method has its particular advantages and disadvantages. Because no one reagent can be considered the ideal or best protein assay method for all circumstances, most researchers have more than one type of protein assay available in their laboratories.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
Unfortunately, no protein assay method exists that isn’t affected by any non-protein component or uniformly sensitive to all protein types. One must select an appropriate assay method based on compatibility with the sample type or one that requires the least manipulation of the sample to accommodate the assay. Most researchers will have more than one type of assay available in their laboratories.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
We offer several types of protein assays including the: BCA Assay, BCA-RAC (Reducing Agent Compatible) Assay, Micro BCA Assay, 660 nm Protein Assay, Pierce Bradford Plus Protein Assay Kit, Pierce Bradford Protein Assay Kit, Modified Lowry Assay, colorimetric and fluorometric Peptide Assays, CBQCA kit, EZQ kit, Quant-iT kits, NanoOrange, and the Qubit kits.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
The USB that comes with the Qubit 2.0 Fluorometer is 2 GB, and the one that comes with the Qubit 3.0 and 4.0 Fluorometer is 4 GB.
We will replace the instrument. Please contact our Technical Support department for details by emailing techsupport@thermofisher.com.
No. The warranty will be voided if the instrument is disassembled or if you attempt to repair the instrument. It is best to call or email our technical support team for assistance.
There are two light sources in the Invitrogen Qubit Fluorometers - both are LEDs. They are expected to last at least 5 years.
The diluted standards can be used for up to 3 hours if using the same working solution for the samples. The Qubit reagents diluted in buffer are stable for up to 3 hours. Evaporation would result in a higher concentration of dye and sample, if present, and this would affect the results.
The Invitrogen Qubit 3.0 and 4.0 Fluorometers can store up to 1,000 samples' worth of data in a .csv file.
The Invitrogen Qubit 2.0 Fluorometer can store up to 200 lines of data in a .csv file.
The original Invitrogen Qubit (1.0) Fluorometer can store up to 20 lines of data in a .csv file.
Yes, these kits will work with all Qubit Fluorometers.
Yes, the Qubit 4.0 Fluorometer comes with both a USB and cable to connect to a computer.
Yes, the Invitrogen Qubit&trade 3.0 Fluorometer will be discontinued.
The Qubit Fluorometer quantifies DNA, RNA, and protein with superior accuracy, sensitivity, and simplicity. It is designed for molecular biology labs working with precious samples that are rare or difficult to process, and applications requiring precise measurement such as real-time PCR. See more about the Qubit Fluorometer (http://www.thermofisher.com/us/en/home/life-science/laboratory-instruments/fluorometers/qubit/qubit-fluorometer.html.html).