L’échelle de protéines non colorée Thermo Scientific PageRuler est un mélange de 14 protéines recombinantes hautement purifiées et non coloréesAfficher plus
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Quantité
26614
2 x 250 μl
26614X4
8 x 250 μL
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Référence 26614
Prix (EUR)
104,00
Each
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Quantité:
2 x 250 μl
Grand volume ou format personnalisé
Prix (EUR)
104,00
Each
Ajouter au panier
L’échelle de protéines non colorée Thermo Scientific PageRuler est un mélange de 14 protéines recombinantes hautement purifiées et non colorées (10 à 200 kDa) à utiliser comme étalons de taille lors de l’électrophorèse de protéines (SDS-PAGE) et des transferts Western. L’échelle de protéines est prête à l’emploi pour le chargement direct sur les gels ; nul besoin de la chauffer, de la réduire ou d’ajouter un tampon d’échantillon avant de l’utiliser.
Caractéristiques du produit • Bandes de référence : la bande de 50 kDa est plus intense que les autres pour une orientation facile • Marquée : les protéines de l’échelle contiennent une séquence Strep-tag™ II intégrale et peuvent être détectées lors des transferts Western à l’aide de conjugués Strep-Tactin™ ou d’un anticorps contre la séquence Strep-tag™ II
Applications • Dimensionnement précis des protéines sur gels de polyacrylamide SDS et transferts Western
Usage exclusivement réservé à la recherche. Ne pas utiliser pour des procédures de diagnostic.
Conditions d’expéditionHomologué pour des expéditions sur de la glace carbonique ou mouillée
Type de colorationNon coloré
Type de systèmeTransfert Western, SDS-PAGE
Number of Markers14
Plage de dimensions10 à 200 kDa
Unit SizeEach
Contenu et stockage
Contenu : deux flacons de 250 μl chacun, protéines de 0,02 à 0,05 mg/ml de chaque
Tampon de stockage : 62,5 mM de Tris-H3PO4 (pH 7,5 à 25°C), 1 mM d’EDTA, 2 % de SDS, 10 mM de DTT, 1 mM de NaN3, 0,01 % de bleu de bromophénol et 33 % de glycérol
Stockage : Dès réception, conserver à -20°C
Foire aux questions (FAQ)
The upper bands of the ladder are missing. What could be the reason?
The upper bands of the ladder may be degraded by proteases. Ladder, gel, buffer, pipettes, pipette tips, or equipment can be contaminated by proteases during usage. A general recommendation would be to avoid working with proteases in the same room. We would recommend preparing fresh solutions, cleaning the equipment, and using clean pipettes and tips. If the ladder itself is contaminated, please use a new tube of the ladder.
Some additional bands or smears were observed on the gel when using a PageRuler unstained ladder. What may have caused this?
Additional bands can appear due to dithiothreitol (DTT) oxidation in the storage buffer. Please add newly prepared DTT solution to the final concentration of 100 mM and boil for 5 min at 95 degrees C. This should solve the issue. Addition of DTT is NOT recommended for prestained protein ladders, since too high a concentration of reducing agents can cause protein destaining.
Do the proteins in Thermo Scientific protein ladders have a His-Tag or would otherwise react with an anti-His-Tag antibody?
No, proteins in Thermo Scientific protein ladders are not His tagged. However, non-specific interaction between the ladder proteins and primary or secondary antibodies is possible and some His-Tag detection systems, such as Thermo Scientific 6xHis Protein Tag Stain Reagent Kit, show non-specific interaction. The protein ladder bands are more readily detected when using high antibody concentrations. The non-specific cross-reactivity is difficult to predict, it often has a different pattern dependent on the antibodies used in each individual experiment. The most general way to handle this problem would be to use lower concentrations of antibodies and to use lower amount of protein ladders. It may also be useful to leave one empty well between the ladder and the sample to overcome a possible leakage of the signal to the nearby sample lane.
Can Thermo Scientific protein ladders be detected by Strep-Tactin conjugates?
PageRuler Unstained protein ladders can be detected directly on Western blots by using Strep-Tactin conjugates or an antibody against the Strep-tag II sequence. All PageRuler and Spectra ladder proteins contain an integral Strep-tag II sequence, however the prestained ladders cannot be detected by Strep-Tactin conjugates.
Why is non-specific binding detected after Western blot?
Protein ladder bands can sometimes be detected with chemiluminescent techniques due to non-specific interactions of ladder proteins with either primary or secondary antibodies (or with both). The ladder bands are only rarely detected by chromogenic substrates. The extremely high sensitivity of the chemiluminescent assays is needed to see the bands, so the actual degree of cross-reactivity is low. The non-specific cross-reactivity is difficult to predict, it often has a different pattern depending on the antibodies used. If antibodies recognize a linear epitope, the cross-reactivity may be due to sequence homology. If antibodies react with a denaturation-resistant conformational epitope it could be impossible to identify the exact reason for detected cross-reactivity. The most general way to handle this problem would be to use lower concentrations of antibodies.