Home Biochemistry Setting Up and Running Mini-PROTEAN® TGX™ Precast Gels
Steps
  1. 1 Open the TGX gel package and remove tape 00:27
  2. 2 Assemble electrode module with TGX gels 01:38
  3. 3 Place electrode module in Tetra cell tank 02:15
  4. 4 Remove comb and fill with running buffer 02:43
  5. 5 Load samples and start electrophoresis 03:37
  6. 6 Stop run and remove gels from core 04:18
  7. 7 Open gel cassette and separate plates 04:51
  8. 8 Remove gel and prepare for analysis 05:30
Biochemistry Bio-Rad Laboratories

Setting Up and Running Mini-PROTEAN® TGX™ Precast Gels

Protocol
Difficulty
intermediate

Steps

1
Open the TGX gel package and remove tape

Remove the TGX gel from the foil and plastic-lined pouch by tearing at the notch. Peel off the tape from the bottom of the cassette gently but firmly.

▶ 00:27
2
Assemble electrode module with TGX gels

Open the wing clamps on the electrode assembly module, load the TGX gels with the short plate facing inside, then close each wing clamp firmly to secure them.

▶ 01:38
3
Place electrode module in Tetra cell tank

Position the electrode assembly module into the Tetra cell tank, aligning the banana plugs with the tabs and ensuring the red anode marking lines up with the red hatch mark on the tank. Add the companion module if running three or four gels.

▶ 02:15
4
Remove comb and fill with running buffer

Grasp the comb from the center notch and lift straight up and out. Fill the inner chambers first, then the outer chamber with running buffer to the appropriate mark (2 or 4 gels). Rinse the wells with a transfer pipet.

▶ 02:43
5
Load samples and start electrophoresis

Load protein samples into the wells. Place the lid on the Tetra tank, matching the colored electrodes on the lid to the electrode posts. Start the run and monitor until the sample dye front reaches the reference marker at the cassette bottom.

▶ 03:37
6
Stop run and remove gels from core

Turn off the power supply and remove the leads. Remove the Tetra cell lid and pour out the buffer. Open each wing clamp and remove the gels from the core assembly.

▶ 04:18
7
Open gel cassette and separate plates

Use the opening lever supplied with the gel box, inserting the arrow between the cassette plates at each of the four marked points. Wedge the teeth of the lever between the plates and crack them open with upward or downward motion at all four points.

▶ 04:51
8
Remove gel and prepare for analysis

Peel the cassette plates apart. Remove the gel by inverting it over a buffer-filled tray to let it peel from the plate, or pick it up from the bottom and place it directly into staining solution.

▶ 05:30

🚨 Failure Case Library (9) + Submit your own case

critical
No Protein Detected: Target Protein Expression Issues
No target protein signal detected in IP eluate. Input lysate may also show weak or absent target protein signal when analyzed separately.
💡 4 · ✓ 5
severe
Uneven Bands Due to Improper Gel Polymerization
Bands appear distorted, wonky, or uneven across lanes. In extreme cases, the same protein appears at different molecular weights in different lanes due to irregular gel matrix formation.
💡 4 · ✓ 4
severe
IgG Heavy/Light Chains Obscure Target Signal
Strong bands at approximately 50 kDa (heavy chain) and 25 kDa (light chain) obscure target protein signal. Same host species used for IP antibody and western blot detection antibody.
💡 4 · ✓ 4
moderate
Band Warping from Well Overloading
Individual lanes show warped or distorted bands while adjacent lanes appear normal. Affected lanes may show smearing, broadening, or lateral spreading of protein bands.
💡 4 · ✓ 4
moderate
Protein of Interest Obscured by Antibody Heavy/Light Chains in IP-Western Blot
When performing Western blot detection of immunoprecipitation samples using secondary antibodies, two prominent bands consistently appear at 50 kDa (heavy chain) and 25 kDa (light chain), obscuring or interfering with detection of the protein of interest if it migrates near these molecular weights.
💡 4 · ✓ 5
moderate
Target Signal Masked by IgG Heavy/Light Chains
Western blot after IP shows strong bands at ~25 kDa and ~50 kDa obscuring target protein. Target protein migrating near these molecular weights cannot be detected due to overwhelming IgG signal.
💡 3 · ✓ 5
moderate
Uneven Dye Front and Band Distortion
The dye front shows curving or warping during migration, resulting in uneven band patterns. Bands may appear tilted, curved, or compressed in certain regions of the gel.
💡 4 · ✓ 4
moderate
Smile Effect on Western Blot Bands
Bands appear curved in a smile-shaped pattern across the gel, with edges migrating faster than the center. This distortion affects all lanes uniformly and compromises molecular weight estimation.
💡 4 · ✓ 4
minor
Multiple Bands from Isoforms or PTMs
Multiple specific bands appear at different molecular weights in IP lane. Input control shows same pattern, indicating genuine protein variants rather than non-specific binding.
💡 4 · ✓ 4
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