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View additional product information for Novex™ Tris-Glycine Plus Midi Protein Gels, 4 to 12%, 1.0 mm - FAQs (WXP41212BOX, WXP41226BOXA, WXP41226BOX, WXP41220BOX, WXP41220BOXA, WXP41212BOXA)
40 product FAQs found
丙烯酰胺比例低于10%的凝胶具有较大的孔，胶体会渗透入孔并将其封闭，从而产生较高的背景。为降低过高的背景，可将凝胶在25%甲醇溶液中孵育，直至获得清晰的背景。应注意，这样做会部分去除条带上的染料，在>25%甲醇溶液中长时间孵育会导致蛋白质条带和背景完全脱色。
使用NuPAGE Invitrogen Bis-Tris凝胶/小肽附带的实验方案，可能会降低背景。该实验方案包含额外的固定步骤以除去多余的SDS，SDS是一种抗胶体试剂，可导致较高背景。染色液的低pH条件可固定凝胶，但没有NuPAGE实验方案特有的预固定步骤速度快。
•再次检查凝胶底部的胶带是否移除。
•确保凝胶安装方向正确，即凝胶盒较高的一面（有印刷字体）面向电泳装置的外侧。
•确保在缓冲液槽内部加入了足够的缓冲液，可浸没上样孔。若未浸没上样孔，检查是否有泄漏并重新封装。
•再次检查电极或Mini cell装置的连接处是否有松动。
•检查电源。
您可购买ZOOM转接头，货号ZA10001，帮助您将导线连接到电源上。
我们建议在安装上样缓冲区之前，使用记号笔在凝胶盒上标记出孔的底部。此外，我们也推荐将光源正确放置在XCell SureLock装置后方，照亮实验台区域。
以下是可能原因和解决方案：
1. 缓冲液稀释过度：检查缓冲液配方；必要时，重新配制。
2. 上样缓冲区泄漏：确保凝胶盒夹安置稳固，垫片在原位，且凝胶盒夹已锁定。
3. 电压设置过低：设置正确的电压。
若使用了含抗氧化剂NuPAGE电泳缓冲液进行Tris-甘氨酸凝胶电泳，可能出现这种情况。请确保在Tris-甘氨酸凝胶电泳时使用正确的Tris-甘氨酸电泳缓冲液。
这可能是由于：
•孔中有碎片
•样品含盐量高（确保盐浓度不超过50–100 mM）
•电泳缓冲液存在问题
•制胶错误
这可能是由凝胶聚合问题和错误的样品制备（最终样品稀释度低于1X）所致。请尝试使用不同批次的相同凝胶，并确保样品正确制备。
可能原因：
还原剂过多（β-巯基乙醇）
皮肤蛋白污染物（角蛋白）
解决方案：
即将上样前，在平衡缓冲液中加入碘乙酰胺，该方法已被证明能消除这种人为条带。
处理凝胶和上样时，使用新鲜的电泳溶液并戴手套。使用高度敏感的染料时，更易出现这种问题。
可能原因：
•上样错误，导致样品残留污染了相邻孔
•电泳缓冲液污染
•凝胶灌制错误：畸形孔
解决方法：
•使用凝胶上样器将样品加到孔中
•减少上样体积
•不要延迟上样
•不要延迟电泳，因为蛋白质会水平扩散；满孔与空孔相邻时，满孔会随时间推移而逐渐污染空孔。
可能原因为：
•上样孔周围的聚合较差
•样品的盐浓度较高
•凝胶界面不均匀
•凝胶安装到夹子上时，对凝胶板造成的压力过大
•凝胶加热不均匀
•凝胶中有不溶物质或整块凝胶上的孔径不一致
•电泳时有气泡
解决方法：
•采用透析、Sephadex G-25或任何其他脱盐柱或使用Amicon浓缩管去除过多的盐或其他物质。
•电泳时，使用冷却装置或降低电流。
凝胶脱离凝胶盒的原因可能是：
•过期的凝胶发生降解。
•凝胶保存方式不恰当。
•电泳期间，电流过大导致过多的热量积累。
•聚丙烯酰胺聚合不充分。
鬼带通常被认为是由于凝胶从盒中轻微脱离（lift），导致一些样品流出到其正常迁移点之外。然后它积累起来显示为微弱的第二条带。
出现“微笑”条带可能是因为凝胶中的丙烯酰胺分解，使蛋白质迁移的基质变少。我们建议您确认使用的凝胶未超过有效期。
杠铃形条带可能是由上样量过大所致。当上样量很大时，一部分样品会扩散到孔的边缘。电泳开始后样品通过浓缩胶部分，样品不完全浓缩会使扩散到孔边缘的部分样品出现轻微滞后。较大的蛋白质在低浓度丙烯酰胺的浓缩胶中迁移阻力更大，会加剧这种效应。为缓解这一问题，我们推荐浓缩蛋白质并减少上样量。这会形成“较薄的”起始区域。
以下是可能原因和解决方案：
1. 上样量太大：上样量不要过大
2. 还原剂不新鲜：上样前正确还原样品，不要使用保存在还原剂中的样品
3. 电泳过程中，蛋白质再氧化：使用NuPAGE凝胶电泳时，在电泳缓冲液中加入抗氧化剂
4. 存在高度疏水性区域，在此区域内蛋白质排斥SDS：上样时，使用2X样品缓冲液代替1X
5. 样品含盐过多：沉淀，并使用低盐缓冲液重悬
6. 样品中SDS不足：在阴极槽加SDS（尝试0.1%、0.2%、0.3%和0.4%）
No. They must be stored at 4 degrees C.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Tris-Glycine Plus Midi Gels can use standard Tris-Glycine sample and running buffers. If you want to run under native conditions, we recommend using sample and running buffers that do not contain SDS (or our Native Tris-Glycine premade buffers).
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
We were able to optimize shelf life of the gels through a proprietary gel formulation change. Unfortunately, we are unable to provide specific details on the chemical changes.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Tris-Glycine Plus Midi Gels have a shelf life of up to 1 year depending upon gel percentages. The minimum shelf life of these gels is at least 6 months from date of manufacture.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Yes, Tris-Glycine Plus Midi Gels can be run in the Bio-Rad Criterion tank with the help of adapters. If you are interested in running these gels in the Bio-Rad Criterion tank, we recommend buying the versions of these gels that come with adapters.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Yes, the current Tris-Glycine Midi Gels will be discontinued on December 31 2017.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Background is generally higher in gels with less than 10% acrylamide percentage due to penetration and trapping of colloids within the large pores of these gels. Excess background may be reduced by incubating the gel in 25% methanol solution until a clear background is obtained. Be aware that the dye will also be partially removed from the bands and that prolonged incubation in >25% methanol will result in complete destaining of protein bands and background.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
It may be possible to reduce background by using the protocol provided for NuPAGE Invitrogen Bis-Tris gels/Small Peptides. This protocol incorporates an extra fix step to remove excess SDS, which can act as an anti-colloidal agent and lead to higher background. The low pH of the staining solution will fix the gel, but not as fast as the pre-fix step specified in the NuPAGE protocol.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
*Double check that the tape on the bottom of the gel has been removed.
*Make sure that the gel(s) are oriented so that the taller sides of the cassette (with the printing) are facing the outside of the electrophoresis unit.
*Make sure that the inner buffer chamber is filled sufficiently so that the wells are covered with buffer. If the wells are not covered, check for leaks and reseal.
*Double check to see if there are any loose electrodes or connections on the Mini cell unit.
*Check the power supply unit.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
You may purchase the ZOOM adapters, Cat. No. ZA10001 to help you connect your leads to the power supply
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
We recommend marking the cassette at the bottom of the wells with a marker pen prior to assembling the Upper buffer chamber. Also, we recommend illuminating the bench area with a light source placed directly behind the XCell SureLock unit.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Here are possible causes and solutions:
1) Buffers are too dilute: Check buffer recipe; remake if necessary.
2) Upper buffer chamber is leaking: Make sure the buffer core is firmly seated, the gaskets are in place and the gel tension lever is locked.
3) Voltage is set too low: Set correct volatage
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
This can happen if Tris-Glycine gels are run using NuPAGE Running buffer containing Antioxidant. Please make sure that the correct Tris-Glycine Running buffer is used with Tris-Glycine gels.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
This could be due to:
*Debris in the well
*High salt in the sample (make sure that the salt concentration does not exceed 50-100 mM)
*Running buffer issue
*Gel casting error
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
This could be due to a gel polymerization issue combined with incorrect sample preparation (final sample dilution less than 1X). Please try a different lot of the same gel and make sure that the sample is correctly prepared.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Possible cause:
*Excess reducing agent (beta-mercaptoethanol)
*Skin protein contaminants (keratin)
Remedy:
*The addition of iodoacetamide to the equilibration buffer just before applying the sample to the gel has been shown to eliminate these artifact bands.
*Use new electrophoretic solutions and wear gloves when handling and loading the gel. This issue is more common when highly sensitive stains are used.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Possible cause:
*Carry-over contamination of sample from one well into neighboring wells due to loading error
*Contaminated running buffer
*Gel casting error: malformed wells
Remedy:
*Use a gel loading tip to load wells
*Reduce the sample volume
*Do not delay while loading wells
*Do not delay after the run, as proteins can diffuse horizontally; a full well left next to an empty well would eventually contaminate the empty well over time.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Possible cause:
*Poor polymerization around sample wells
*High salt concentration in sample
*Uneven gel interface
*Excessive pressure applied to the gel plates when the gel is placed into the clamp assembly
*Uneven heating of the gel
*Insoluble material in the gel or inconsistent pore size throughout the gel
*Air bubble during the run
Remedy:
*Remove excess salt/other material by dialysis, Sephadex G-25 or any other desalting column or using an Amicon concentrator.
*Either use a cooled apparatus or reduce the current at which electrophoresis is performed.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Gel lifting off the cassette can be caused by:
*Expired gels that are degrading
*Improper storage of gels
*Too much heat accumulating during the electrophoresis run due to excessive current
*Insufficient polymerization of the polyacrylamide
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Ghost bands are usually attributed to a slight lifting of the gel from the cassette, which results in the trickling down of some sample beyond its normal migration point. It then accumulates and appears as a faint second band.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
"Smiling" bands may be the result of the acrylamide in the gel breaking down, leaving less of a matrix for the proteins to migrate. We recommend checking to ensure that the gels have not been used past their expiration date.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Barbell shaped bands are a result of loading too large of a sample volume. When a large sample volume is loaded, part of the sample tends to diffuse to the sides of the wells. When the run begins and the sample moves through the stacking portion of the gel, the sample will incompletely stack causing a slight retardation of the portion of the sample that diffused to the sides of the wells. This effect may be intensified for larger proteins, whose migration is more impeded in the low concentration acrylamide of the stacking gel. To alleviate the problem, we recommend concentrating the protein and loading a smaller volume. This gives a "thinner" starting zone.
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.
Here are possible causes and solutions:
1) Sample overload: Do not overload samples
2) Addition of reducing agent that is not fresh: Reduce samples right before loading and do not use samples that have been stored in reducing agent
3)Re-oxidation of the protein during the run: Add antioxidant to the running buffer if you are running NuPAGE gels
4) Presence of highly hydrophobic regions where the protein can exclude SDS: Load the sample with 2X sample buffer instead of 1X sample buffer
5) Excess salt in the sample: Precipitate and reconstitute in lower salt buffer
6) Not enough SDS in the sample: Add SDS to the upper buffer chamber (try 0.1%, 0.2%, 0.3% and 0.4% SDS)
Find additional tips, troubleshooting help, and resources within our Protein Electrophoresis and Western Blotting Support Center.