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PEPotec SRM Custom Peptide Libraries
Custom SRM Peptide Library specifications
| Peptide length | 6–25 amino acids |
| Manufacturing scale | ≥0.1 mg |
| Purity options | Crude (as synthesized) |
| Formulation | Suspended in 0.1% TFA in 50% (v/v) acetonitrile/water |
| Production time | 3–4 weeks |
| Modifications | Variety of modifications and labels, including heavy amino acids (isotope-labeled) |
| C-terminal residue | Lysine or Arginine |
| Counterion | Trifluoroacetic acid (TFA) |
| Delivery format | Peptides are provided in individual 2-D barcoded tubes in 96-tube plates |
Available PEPotec SRM Peptide Library grades
| Grade 1 Fast and easy | Grade 2 Greater analysis | Grade 3 Maximum assurance | |
|---|---|---|---|
| Quality control (QC) | MS check of 5% of peptides | MS check of 100% of peptides | MS check and analysis of 100% of peptides |
| Purity | Crude | Crude | Crude |
| Peptide resynthesis | Not provided | Not provided | One resynthesis |
| Difficult peptide failed synthesis policy | You pay for entire set of peptides ordered | You only pay for peptides successfully synthesized in the requested library | You only pay for peptides successfully synthesized in the requested library |
| Included documentation | Peptide amount | Peptide amount | Peptide amount and MS Spectra |
| Minimum order | 24 peptides | 24 peptides | 24 peptides |
PEPotec SRM Peptide optional heavy amino acids
| Amino acid† | Code | Mass difference | Isotope | Isotopic enrichment |
|---|---|---|---|---|
| Alanine | A | +4 Da | U-13C3, 15N | >99% |
| Arginine | R | +10 Da | U-13C6, 15N4 | >99% |
| Isoleucine | I | +7 Da | U-13C6, 15N | >99% |
| Leucine | L | +7 Da | U-13C6, 15N | >99% |
| Lysine | K | +8 Da | U-13C6, 15N2 | >99% |
| Phenylalanine | F | +10 Da | U-13C9, 15N | >99% |
| Proline | P | +6 Da | U-13C5, 15N | >99% |
| Valine | V | +6 Da | U-13C5, 15N | >99% |
† Other amino acids on request.
PEPotec SRM Peptide optional modifications
Available with all grades on a per-peptide basis**
- C-terminal heavy labeling at R or K
- Internal heavy labeling at A, R, I, L, K, F, P, or V
- Alternative heavy amino acid at C-term
- Alternative light amino acid at C-term
- Phosphorylation at 1–3 sites
- All cysteines protected by carbamidomethylation (CAM)
- Diglycine ubiquitination motif on lysine [Lys(GG)]
- Methionine sulfoxide [Met(O)]
- Acetylation at side chain of lysine [Lys(Ac)]
- Methylation at side chain of lysine [Lys(Me)] and arginine [Arg(Me)]
- Dimethylation at side chain of lysine [Lys(Me)2]
- 3-chloro-tyrosine
- Hydroxyproline (Hyp)
- Isoaspartic acid
- Formylation at C-term
- Carboxymethylcysteine (CMC) at cysteine
** Others available on request.
Documents
Frequently asked questions
Q. What is the shelf life of a peptide?
A. The shelf life is >24 months at –20°C for lyophilized peptides protected by argon in the original non-open container. This is sequence dependent and it may be shorter for some sequences.
Q. Why is PEPotec SRM of higher quality than most competitors?
A. We are synthesizing our PEPotec using the solid phase Fmoc synthesis on resin. Most of our competitors use the spot technology providing poor quality peptides above 15 amino acids.
Q. How many peptide syntheses typically fail?
For peptide synthesis ~2.4% of the peptides submitted, due to difficult sequence were unable to be synthesized. Most of our competitors announce on their website 5%.
Q. What peptide parameters are influenced by amino acid composition?
A. The ability to synthesize the peptide and its solubility, stability, and overall charge are discussed in the Protein Biology Learning Center under the Peptide Design.
Q. What information is needed to obtain an accurate quote?
A. All the information required to get an accurate quote is included in the Quote Request form.
Q. What is the difference between SRM, MRM, and PRM?
A. SRM (Simultaneous Reaction Monitoring) and MRM (Multiple Reaction Monitoring) is the terminology to describe targeted MS quantitation. SRM and MRM quantitation are typically performed on triple quadrupole instruments. PRM (Parallel Reaction Monitoring) is a new technique described by Dr. Josh Coon and Dr. Bruno Domon. PRM is used for the MS quantitation performed on Q-Exactive instruments (e.g., Orbitrap instrumentation).
Custom SRM Peptide Library specifications
| Peptide length | 6–25 amino acids |
| Manufacturing scale | ≥0.1 mg |
| Purity options | Crude (as synthesized) |
| Formulation | Suspended in 0.1% TFA in 50% (v/v) acetonitrile/water |
| Production time | 3–4 weeks |
| Modifications | Variety of modifications and labels, including heavy amino acids (isotope-labeled) |
| C-terminal residue | Lysine or Arginine |
| Counterion | Trifluoroacetic acid (TFA) |
| Delivery format | Peptides are provided in individual 2-D barcoded tubes in 96-tube plates |
Available PEPotec SRM Peptide Library grades
| Grade 1 Fast and easy | Grade 2 Greater analysis | Grade 3 Maximum assurance | |
|---|---|---|---|
| Quality control (QC) | MS check of 5% of peptides | MS check of 100% of peptides | MS check and analysis of 100% of peptides |
| Purity | Crude | Crude | Crude |
| Peptide resynthesis | Not provided | Not provided | One resynthesis |
| Difficult peptide failed synthesis policy | You pay for entire set of peptides ordered | You only pay for peptides successfully synthesized in the requested library | You only pay for peptides successfully synthesized in the requested library |
| Included documentation | Peptide amount | Peptide amount | Peptide amount and MS Spectra |
| Minimum order | 24 peptides | 24 peptides | 24 peptides |
PEPotec SRM Peptide optional heavy amino acids
| Amino acid† | Code | Mass difference | Isotope | Isotopic enrichment |
|---|---|---|---|---|
| Alanine | A | +4 Da | U-13C3, 15N | >99% |
| Arginine | R | +10 Da | U-13C6, 15N4 | >99% |
| Isoleucine | I | +7 Da | U-13C6, 15N | >99% |
| Leucine | L | +7 Da | U-13C6, 15N | >99% |
| Lysine | K | +8 Da | U-13C6, 15N2 | >99% |
| Phenylalanine | F | +10 Da | U-13C9, 15N | >99% |
| Proline | P | +6 Da | U-13C5, 15N | >99% |
| Valine | V | +6 Da | U-13C5, 15N | >99% |
† Other amino acids on request.
PEPotec SRM Peptide optional modifications
Available with all grades on a per-peptide basis**
- C-terminal heavy labeling at R or K
- Internal heavy labeling at A, R, I, L, K, F, P, or V
- Alternative heavy amino acid at C-term
- Alternative light amino acid at C-term
- Phosphorylation at 1–3 sites
- All cysteines protected by carbamidomethylation (CAM)
- Diglycine ubiquitination motif on lysine [Lys(GG)]
- Methionine sulfoxide [Met(O)]
- Acetylation at side chain of lysine [Lys(Ac)]
- Methylation at side chain of lysine [Lys(Me)] and arginine [Arg(Me)]
- Dimethylation at side chain of lysine [Lys(Me)2]
- 3-chloro-tyrosine
- Hydroxyproline (Hyp)
- Isoaspartic acid
- Formylation at C-term
- Carboxymethylcysteine (CMC) at cysteine
** Others available on request.
Documents
Frequently asked questions
Q. What is the shelf life of a peptide?
A. The shelf life is >24 months at –20°C for lyophilized peptides protected by argon in the original non-open container. This is sequence dependent and it may be shorter for some sequences.
Q. Why is PEPotec SRM of higher quality than most competitors?
A. We are synthesizing our PEPotec using the solid phase Fmoc synthesis on resin. Most of our competitors use the spot technology providing poor quality peptides above 15 amino acids.
Q. How many peptide syntheses typically fail?
For peptide synthesis ~2.4% of the peptides submitted, due to difficult sequence were unable to be synthesized. Most of our competitors announce on their website 5%.
Q. What peptide parameters are influenced by amino acid composition?
A. The ability to synthesize the peptide and its solubility, stability, and overall charge are discussed in the Protein Biology Learning Center under the Peptide Design.
Q. What information is needed to obtain an accurate quote?
A. All the information required to get an accurate quote is included in the Quote Request form.
Q. What is the difference between SRM, MRM, and PRM?
A. SRM (Simultaneous Reaction Monitoring) and MRM (Multiple Reaction Monitoring) is the terminology to describe targeted MS quantitation. SRM and MRM quantitation are typically performed on triple quadrupole instruments. PRM (Parallel Reaction Monitoring) is a new technique described by Dr. Josh Coon and Dr. Bruno Domon. PRM is used for the MS quantitation performed on Q-Exactive instruments (e.g., Orbitrap instrumentation).
Resources
For Research Use Only. Not for use in diagnostic procedures.