# Understanding FLAG Peptide Molecular Weight: A Technical Laboratory Perspective
In my years of working with recombinant protein purification and structural analysis, the selection of the correct tag remains a cornerstone of successful experimental design. When researchers ask about flag peptide molecular weight, they are often navigating the nuances between standard octapeptide tags and their more complex counterparts.
From my experience in sourcing high-quality biochemical markers, the first step is distinguishing between 3x DYKDDDDK peptide, also called 3x FLAG peptide, is a 23 aa length peptide used for the competitive elution of DYKDDDDK-tag … the classic FLAG-ta A fusion tag, called DYKDDDDK and consisting of eight amino acids (Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys) including an enterokinase … g and the 3X variant.
The standard FLAG peptide—often referred to by the sequence Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys (DYKDDDDK)—possesses a precise molecular weight of approximately 1012.97 Da. My laboratory notes indicate this empirical formula is C41H60N10O20. The inclusion of multiple acidic residues, particularly L-aspartic acid, Flag peptide | C41H60N10O20 | CID 9854670 - PubChem makes this octapeptide highly effective for specific binding applications.
When higher affinity is required, I often shift to the 3X FLAG peptide. This version is significantly larger, consisting of twenty-three amino acids (MDYKDHDG FLAG Tag Size The molecular weight of the DYKDDDDK-tag (FLAG-tag) is 1012 Da. The multiple polyanionic amino acids in the … DYKDHDIDYKDDDDK). Consequently, its molecular weight reaches 2861.87 Da (with an empirical formula of C120H169N31O49S). Understanding this discrepancy is crucial when evaluating why *flag tagged proteins have higher molecular weight* than initial calculations might suggest.
Observations on Solubility and Application
One common *search intent* related to these tags involves understanding how to e A fusion tag, called DYKDDDDK and consisting of eight amino acids (Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys) including an enterokinase … ffectively solubilize these reagents for consistent elution processes. I frequently utilize PBS to prepare working solutions. In my workflow, achieving a concentration of 100 mg/mL (98.72 mM) often requires careful ultrasonic agitation to ensure the solution remains clea Why do flag tagged proteins have higher molecular … r and fully functional.
When documenting *why do flag tagged proteins have higher molecular weight than the expectation*, it is important to consider the potential for post-translational modifications or the inherent size of the epitope tag itself. If you are performing a *competitive elution of DYKDDDDK-tag*, the 3X peptide variant is generally superior due to its increased length and higher binding sensitivity.
Technical Specifications and Verification
For researchers performing rigorous data analysis, referencing the exact CAS numbers is mandatory 3x FLAG peptide - novoprolabs.com for inventory management. The standard FLAG peptide corresponds to CAS 98849-88-8, while the widely used 3X FLAG peptide follows CAS 402750-12-3.
Whether you are conducting *immunodetection* or seeking to optimize *affinity purification* protocols, the reliability of these synthetic molecules is unparalleled. I have found that high-purity variants with >95% purity profiles offer the best signal-to-noise ratios. It is always a good practice to verify the N-terminus (NH2) and ensure the peptide length matches your specific detection platform requirements.
Practical Tips from the Bench
* Elution Strategy: When working with 3X FLAG, I typically dilute my stock 5-fold with TBS to maintain a 1 mg/mL working concentration, which is usually optimal for protein release from affinity matrices.
* Storage and Stability: Always consult the datasheet for thermal stability. While these peptides are robust, maintaining them under controlled conditions ensures that you avoid degradation, which could otherwise interfere with the *sensitivity and specificity* of your assays.
* Documentation: Always track whether you are utilizing the 8-amino acid synthetic octapeptide CAS 402750-12-3. Molecular Weight 2861.91. Browse 3X FLAG PEPTIDE and related products at MilliporeSigma. or the 23-amino acid polypeptide, as this size difference is the primary factor in troubleshooting unexpected migration patterns during electrophoretic analysis.
By staying mindful of the molecular mass differentials—specifically the ~1013 Da range for the standard tag versus the ~2862 Da range for the 3X tag—I have been able to refine my purification yields significantly. This technical precision is what differentiates a standard procedure from a truly optimized experiment.
# Understanding FLAG Peptide Molecular Weight: A Technical Laboratory Perspective
In my years of working with recombinant protein purification and structural analysis, the selection of the correct tag remains a cornerstone of successful experimental design. When researchers ask about flag peptide molecular weight, they are often navigating the nuances between standard octapeptide tags and their more complex counterparts.
From my experience in sourcing high-quality biochemical markers, the first step is distinguishing between 3x DYKDDDDK peptide, also called 3x FLAG peptide, is a 23 aa length peptide used for the competitive elution of DYKDDDDK-tag … the classic FLAG-ta A fusion tag, called DYKDDDDK and consisting of eight amino acids (Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys) including an enterokinase … g and the 3X variant.
The standard FLAG peptide—often referred to by the sequence Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys (DYKDDDDK)—possesses a precise molecular weight of approximately 1012.97 Da. My laboratory notes indicate this empirical formula is C41H60N10O20. The inclusion of multiple acidic residues, particularly L-aspartic acid, Flag peptide | C41H60N10O20 | CID 9854670 - PubChem makes this octapeptide highly effective for specific binding applications.
When higher affinity is required, I often shift to the 3X FLAG peptide. This version is significantly larger, consisting of twenty-three amino acids (MDYKDHDG FLAG Tag Size The molecular weight of the DYKDDDDK-tag (FLAG-tag) is 1012 Da. The multiple polyanionic amino acids in the … DYKDHDIDYKDDDDK). Consequently, its molecular weight reaches 2861.87 Da (with an empirical formula of C120H169N31O49S). Understanding this discrepancy is crucial when evaluating why *flag tagged proteins have higher molecular weight* than initial calculations might suggest.
Observations on Solubility and Application
One common *search intent* related to these tags involves understanding how to e A fusion tag, called DYKDDDDK and consisting of eight amino acids (Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys) including an enterokinase … ffectively solubilize these reagents for consistent elution processes. I frequently utilize PBS to prepare working solutions. In my workflow, achieving a concentration of 100 mg/mL (98.72 mM) often requires careful ultrasonic agitation to ensure the solution remains clea Why do flag tagged proteins have higher molecular … r and fully functional.
When documenting *why do flag tagged proteins have higher molecular weight than the expectation*, it is important to consider the potential for post-translational modifications or the inherent size of the epitope tag itself. If you are performing a *competitive elution of DYKDDDDK-tag*, the 3X peptide variant is generally superior due to its increased length and higher binding sensitivity.
Technical Specifications and Verification
For researchers performing rigorous data analysis, referencing the exact CAS numbers is mandatory 3x FLAG peptide - novoprolabs.com for inventory management. The standard FLAG peptide corresponds to CAS 98849-88-8, while the widely used 3X FLAG peptide follows CAS 402750-12-3.
Whether you are conducting *immunodetection* or seeking to optimize *affinity purification* protocols, the reliability of these synthetic molecules is unparalleled. I have found that high-purity variants with >95% purity profiles offer the best signal-to-noise ratios. It is always a good practice to verify the N-terminus (NH2) and ensure the peptide length matches your specific detection platform requirements.
Practical Tips from the Bench
* Elution Strategy: When working with 3X FLAG, I typically dilute my stock 5-fold with TBS to maintain a 1 mg/mL working concentration, which is usually optimal for protein release from affinity matrices.
* Storage and Stability: Always consult the datasheet for thermal stability. While these peptides are robust, maintaining them under controlled conditions ensures that you avoid degradation, which could otherwise interfere with the *sensitivity and specificity* of your assays.
* Documentation: Always track whether you are utilizing the 8-amino acid synthetic octapeptide CAS 402750-12-3. Molecular Weight 2861.91. Browse 3X FLAG PEPTIDE and related products at MilliporeSigma. or the 23-amino acid polypeptide, as this size difference is the primary factor in troubleshooting unexpected migration patterns during electrophoretic analysis.
By staying mindful of the molecular mass differentials—specifically the ~1013 Da range for the standard tag versus the ~2862 Da range for the 3X tag—I have been able to refine my purification yields significantly. This technical precision is what differentiates a standard procedure from a truly optimized experiment.