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Spot-Cap® is a Nanobody-based affinity resin optimized for one-step protein purification of Spot-tagged proteins.

More information about the Spot capture and detection tag here.

Spot-Tag sequence PDRVRAVSHWSS.

Protein purification
For immunoprecipitation (IP), Co-IP, Co-IP/MS use Spot-Trap

When use Spot-Cap? When use Spot-Trap? Click here.

One-step protein purification
High binding capacity
Multiple regeneration cycles
Effective elution at 4°C with Spot-peptide or pH shift

Spot Affinity Gel
Spot Affinity Matrix

Product Size Code Price Buy
Product Spot-Cap™ Size 2 mL Code eca-2 Price $ 1690
Buy +
Product Spot-Cap™ and peptide Size 0.1 mL; 1 mg Code eca-ep Price $ 170
Buy +
Product Spot-peptide Size 1 mg Code ep-1 Price $ 85
Buy +
Product Spot-peptide Size 10 mg Code ep-10 Price $ 450
Buy +

Product type
anti-Spot-Tag Nanobody (VHH) conjugated to agarose beads

Binding capacity
10 mg protein (30 kDa) / 1 mL settled resin (340 nmol / 1 mL settled resin)

Spot-Tag sequence motif PDRVRAVSHWSS

Elution conditions
0.1 mM Spot-peptide or 100 mM glycine pH 2.0 at 4°C

Regeneration buffer
100 mM glycine pH 2.0

>5 cycles

Purification format
Batch and gravity flow

50% slurry

Matrix, particle size
4% agarose, 90 µm 

pH range for purification
pH 4 - 11

Chemical stability
1 M NaCl, 2 M Urea, 10 mM DTT, 10 mM ß-mercaptoethanol, 10 mM TCEP, 2% DDM, 2% NP-40, 2% Triton X-100


Storage instructions
Shipped at ambient temperature. Upon receipt store at 4°C. Stable for one year.


  • Economic: high binding capacity and multiple regeneration cycles
  • Fast and gentle one-step purification at 4°C preserves protein stability and function
  • Tight and highly selective binding of a single repeat Spot-Tag
  • High specificity leads to minimal contamination of host cell proteins 
  • No contamination of antibody heavy and light chains


  • One-step purification with high purity and yield reduces costs and efforts
  • Constant high purification results over >5 regeneration cycles
  • High binding capacity and high elution efficiency 
  • Effective elution at acidic conditions or with Spot-peptide in a concentration of just 0.1 mM. Other purification resins require high peptide concentration of up to 2 mM for elution.


  • For any kind of protein, especially low expressed or sensitive proteins, membrane or secreted proteins, metalloproteins and multiple subunit protein complexes.
  • Broad buffer compatibility and inert tag allow easy integration in experimental workflows
  • Suitable for all commonly used expression hosts, e.g. bacteria, yeast, insect cells, and mammalian cells
  • Engineered for optimal elution efficiency and high yield at 4°C in batch or gravity flow formats

Spot-Tag: Inert 12 amino acid peptide tag

  • Sequence: PDRVRAVSHWSS (1.4 kDa)
  • Short, flexible Spot-Tag preserves folding and function of fusion protein
  • N- and C-terminal fusion for flexibility in cloning and protein expression
  • No tag removal needed after purification because Spot-Tag is compatible to most biochemical assays

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Only for research applications, not for diagnostic or therapeutic use!