Protein Expression & Analysis

Epitope Tag Antibodies

A comprehensive guide to detecting, localizing, and purifying recombinant proteins using highly validated, high-affinity tag antibodies.

Epitope tagging is a powerful and universally applied technique in molecular biology that allows for the precise detection, localization, and rapid purification of any protein of interest.

By fusing your target protein with a small, well-characterized peptide sequence (the epitope tag) via recombinant DNA technology, you can utilize a single, high-affinity commercial antibody to reliably study your protein. This technique is completely indispensable when a reliable, specific primary antibody for your native target protein does not currently exist.

Our comprehensive portfolio of monoclonal and polyclonal epitope tag antibodies provides a highly specific and convenient solution for all your protein expression and analysis needs, ranging from Western Blotting and Immunofluorescence to Co-immunoprecipitation (Co-IP).

2. Choosing the Right Epitope Tag

Selecting the correct tag depends heavily on your downstream application. Tags are generally divided into two categories based on their size and effect on the recombinant protein.

A

Small Peptide Tags (e.g., FLAG, HA, Myc, His)

These tags are typically 6 to 15 amino acids long. Because of their minimal size, they are highly unlikely to interfere with the native folding, trafficking, or biological activity of your target protein. They are primarily used for detection (Western Blot, IHC) and immunoprecipitation.

B

Large Protein Tags (e.g., GST, MBP, GFP)

These tags add significant molecular weight to your target (e.g., GST adds ~26 kDa). While they can occasionally cause steric hindrance, they are incredibly useful for enhancing the solubility of difficult-to-express proteins and serve as robust handles for affinity purification (e.g., pulling down GST-tagged proteins using glutathione agarose).

N-Terminal vs. C-Terminal Tagging: The placement of the tag matters. If your protein possesses a critical signaling peptide at the N-terminus (required for secretion or localization), placing a tag there will disrupt its function. In these cases, a C-terminal tag is required. Alternatively, if the C-terminus contains critical interaction domains, N-terminal tagging is preferred.

3. Find Your Antibody by Tag & Application

Browse our essential epitope tag dictionary below to find the exact monoclonal or polyclonal antibody required for your specific application.

Tag Type	Sequence / Target	Validated Clones	Primary Applications
FLAG-tag	DYKDDDDK	Clone M2.1, Clone FG4R, Rabbit PAb	WB, IF/ICC, IP, ELISA
HA-tag	YPYDVPDYA	Clone SQab18117	WB, IF/ICC, IP, ELISA
Myc-tag	EQKLISEEDL	Rabbit PAb	WB, IF/ICC, IP
His-tag	HHHHHH	Clone 1C4, Clone 33D10.D2.G8, Rabbit PAb	WB, IF/ICC, IP, FC
V5-tag	GKPIPNPLLGLDST	Clone SV5-P-K, Clone SQab18114, Rabbit PAb	WB, IF/ICC, IP, IHC-Fr, RIA
T7-tag	MASMTGGQQMG	Clone 3G7, Goat PAb	WB
S-tag	KETAAAKFERQHMDS	Clone N56/9, Rabbit Mab	WB, IHC
GFP-tag	GFP Protein Target	Clone GF28R, Clone 4B10B2, Rabbit PAb (FC Conj)	DOT, ELISA, IHC, IP, WB
RFP-tag	RFP Protein Target	Mouse MaB, Ready-To-Use PAb, Rabbit PAb	WB, IF/ICC, IP, FC
GST-tag	GST Protein Target	Mouse MaB, Rabbit PAb	WB, IP, ELISA
MBP-tag	MBP Protein Target	Mouse MaB, Rabbit PAb	WB, IP

4. Supporting Reagents & Purification

Beyond primary detection antibodies, successful epitope tagging workflows require a suite of supporting reagents. Biorbyt offers custom blocking peptides to validate antibody specificity, conjugated secondary antibodies to streamline your Western Blots, and magnetic/agarose resins for rapid immunoprecipitation.

Validation & Elution Epitope Tag Peptides High-purity synthetic peptides (FLAG, HA, Myc, 3xFLAG) used for competitive blocking in Western blots or gentle, non-denaturing elution during affinity chromatography. Direct Detection Conjugated Tag Antibodies Eliminate the need for secondary antibodies. Explore our primary tag antibodies directly conjugated to HRP, Biotin, or fluorescent dyes (FITC, CF488) to streamline assays. Purification IP & Purification Resins Isolate your recombinant proteins rapidly. We provide high-binding capacity agarose and magnetic beads coupled with Anti-FLAG, Anti-HA, or Nickel (Ni-NTA) for His-tags.