Invitrogen™ NuPAGE Tris-Acetate Protein Gels

Choose the Right NuPAGE Tris-Acetate Gel for Protein Separation

Obtain optimal separation of your high molecular weight proteins by choosing the right combination of gel and running buffer. NuPAGE Tris-Acetate protein gels come in a polyacrylamide concentration of 7% and a 3–8% gradient. Gels come in two sizes: mini (8 cm x 8 cm) or midi (8.7 cm x 13.3 cm) and either 1.0 mm (mini and midi gels) or 1.5 mm (mini gel format only) in thickness. NuPAGE Tris-Acetate gels also come in multiple well formats. Mini gels can be run using our XCell SureLock Mini-Cell or Mini Gel Tank. Midi gels can be run using our XCell4 SureLock Midi-Cell or conveniently with the Bio-Rad Criterion™ Cell using our adapters.



Reliable separation and transfer of high molecular weight (HMW) proteins is a common challenge for life science researchers. Choosing the right gel is a key factor in the successful transfer of HMW proteins. A popular general-use gel is a 4–20% Tris-glycine gel, which can effectively separate a mixed range of proteins. However, HMW proteins will be compressed into a narrow region at the top of the gel. A better option for HMW proteins is a Tris-acetate gel or a low percentage non-gradient Tris-glycine or Bis-Tris gel. When specially targeting HMW proteins, optimal transfer can be achieved with a Tris-acetate gel.

Tris-acetate gels maintain a neutral pH and separate HMW proteins with higher resolution than Bis-Tris or Tris-glycine gels. Comparison of HMW protein separation using different gel chemistries and gradients shows best separation and resolution of HMW proteins using a 3–8% Tris-acetate gel. This increased resolution leads to increased transfer efficiencies and higher sensitivity.



















 

Tris-acetate gels enable the best separation of HMW proteins. (A) Optimal results are obtained in the yellow shaded areas. (B) Better transfer is seen using the tris-acetate gel over a 4–20% Tris-glycine gel: 9 ng is visualized on the Tris-acetate gel versus 620 ng visualized on the tris-glycine gradient gel.

Features NuPAGE Tris-Acetate Gels

• High resolution—gels offer optimal separation of high molecular weight proteins
• Better protein integrity—sample preparation process has been optimized to help preserve your proteins
• Longer shelf life—gels can be stored for at least 8 months

 

The NuPAGE Tris-Acetate Gels use a discontinuous buffer system involving three ions:

• Acetate (–) is from the gel buffer and serves as a leading ion due to its high affinity to the anode relative to other anions in the system. The gel buffer ions are tris (+) and acetate (–) (pH 7.0).
• Tricine (–) is from the running buffer and serves as the trailing ion. The running buffer ions are tris (+), tricine (–) and dodecylsulfate (pH 8.3).
• Tris (+) is the common ion present in the gel buffer and running buffer. The Tris-acetate system also operates at a significantly lower operating pH of 8.1 during electrophoresis.