Custom Peptide Synthesis
AAPPTec custom peptide synthesis and peptide libraries are offered from 2 to 120 amino acids to include modifications of standard peptide structures, including phosphorylation, methylation, labeling with tags or dyes, cyclization, conjugation with PEG, and incorporation of D-amino acids. AAPPTec custom peptide synthesis can provide custom peptides as trifluoroacetic acid (TFA) salts, acetate salts or hydrochloride salts. AAPPTec custom peptide synthesis has been used in proteomics, antibody products, lead discovery in drug development, etc. AAPPTec peptide chemists help you design and synthesize reliable and validated custom peptides.
AAPPTec custom peptide synthesis services provide custom peptides in several purity levels. Typical purity levels are:
1. Immunological Grade (suitable for forming polyclonal antibodies)
2. 80% or greater (tissue culture; ligand for affinity purification; non-quantitative antibody blocking experiments)
3. 90% or greater (in vivo studies; bioassays; markers for electrophoresis; monoclonal antibodies)
4. 95% or greater (ELISA; RIA; enzyme substrate)
5. 98% (NMR; chromatography standards)
In selecting a custom peptide synthesis company, factors to consider in addition to cost are accuracy, success rate and speed of delivery.
Our peptides are available in all scales, from milligram research scale to multi-kilogram production scale. We provide single custom peptides, multiple peptides and custom peptide libraries in a timely manner at competitive prices.
AAPPTec’s experienced peptide chemists quickly and efficiently prepare most peptide sequences. Custom peptide synthesis is AAPPTec’s specialty.
Our chemists have experience and expertise in preparing long peptides in high purity. For example, AAPPTec has synthesized and delivered 78 to 81 amino acid custom peptides at 95% purity.
During each custom peptide synthesis, AAPPTec chemists utilize UV monitoring and in-process tests, such as the Kaiser test, to assure each synthesis step is complete before proceeding with the synthesis. If necessary, double coupling protocols are used to assure complete coupling. In addition, heating may be utilized to accelerate slow or difficult reactions. By assuring complete coupling of each amino acid, AAPPTec chemists maximize overall yield, minimize impurities and reduce the amount of purification required for each custom peptide.
In custom peptides containing hydrophobic sequences where hydrogen bonding of the peptide backbone can result in slow or incomplete reactions, AAPPTec chemists may utilize hydrogen-bond disrupting elements such as pseudoprolines or Dmb-protected amino acids. In some cases, Boc chemistry with in situ neutralization affords higher yields than Fmoc chemistry.
AAPPTec chemists take steps to minimize racemization of the activated amino acid in coupling which leads to undesired diasteromeic peptides. Racemization during activation is minimized by activating the amino acid residue at reduced temperature and adding HOBt which suppresses the rate of racemization. Cysteine and histidine are especially prone to racemization with uronium activating reagents. When racemization of these residues is especially troublesome, AAPPTec chemists may use carbodiimide/HOBt activation which results in lower levels of racemization.
All custom peptide products are provided with a complete quality control package, including HPLC and Mass Spectral Analysis, to confirm the purity and identity of the peptide. From 2 amino acids to 85 amino acids, AAPPTec can prepare peptides in the scale and purity required. We comply with the most stringent quality control specifications for a reasonable price.
Custom Peptide Prices
Our custom peptide prices are determined mainly by three factors: the amount of peptide, the length of the peptide sequence and the amount of purification required. For standard peptides, the purification costs may be a significant part of the custom peptide price. Thus crude peptides are relatively inexpensive, while 95% pure peptides have higher prices than 85% pure peptides. AAPPTec minimizes custom peptide prices by utilizing peptide synthesis protocols that produce crude peptides with high purity, thus reducing the purification costs.
Peptide prices will depend on the purity and quantitity of peptide required. Longer peptides may be more difficult to synthesize due to hydrogen bonding between peptide chains and other factors. Peptides containing 30 amino acids or more and peptides with modifications require special quotations.
To minimize the cost of custom peptides, do not request peptide purity greater than is necessary for your application. The table below lists recommended peptide purities for various applications.
AAPPTec Custom Peptide Purity Levels
Immunological Grade: suitable for forming polyclonal antibodies
80% or Greater: tissue culture; ligand for affinity purification; non-quantitative antibody blocking experiments
90% or Greater: in vivo studies; bioassays; markers for electrophoresis; monoclonal antibodies
95% or Greater: ELISA; RIA; enzyme substrate
98%: NMR; chromatography standards
Custom Peptide Quotations and Ordering
To request a quotation on custom peptide synthesis, use our on-line quote request form or email your peptide sequence, quantity and purity requirements to sales@aapptec.com and put “Custom Peptide Synthesis” in the subject line. Your information will be held in strict confidence.
- All peptides are TFA salt unless it is specified otherwise in the customer’s PO. All custom peptides are peptide salts.
- All peptides are sold only for experimental research, not for use in humans.
- Customer must verify the sequence in the sales order and their PO; AAPPTec is not responsible for mistakes in the sequence or any biological activity
- Custom peptides can not be returned.
Peptide Synthesis Services
Peptide synthesis services that AAPPTec provides include incorporation of non-standard amino acids, modifications at the N-terminal, C-terminal or side chains, and the formation of cyclic structures. Non-standard amino acids can usually be incorporated into a peptide synthesis with little difficulty. Highly expensive building block, such as isotope-labeled amino acids, are incorporated most efficiently and cost effectively near the N-terminal.
N-Terminal Peptide Modifications
N-terminal modifications are made for a variety of purposes. Some modifications improve the stability of the peptide to proteolytic enzymes or improve the absorption and bioavailability of the peptide. Other N-terminal modifications introduce a dye or tag that allows areas where the peptide accumulates to be visualized. Some modifications are immunoadjuncts to enhance antibody production or linkers to allow conjugation of the peptide to other biomolecules.
C-Terminal Peptide Modifications
C-terminal modifications, except for amidation, are less common. They are incorporated either through the utilization of special resins or solution phase reactions after cleavage from the resin. C-terminal modifications can improve the stability of the peptide or alter its interaction with receptors. C-terminal modifications are also used to produce substrates used in enzymatic studies.
Internal Modifications
Internal modifications are incorporated into synthetic peptides by using unusual or specially derivatized amino acids. Some internal modifications, such as D-amino acids, beta-amino acids, and N-methyl amino acids, improve peptide stability to enzymes. Unusual amino acid modifications are often used to optimize peptide binding and selectivity in binding to target molecules or insertion into membranes.. Some internal modifications correspond to post translational modifications in proteins. Some examples are phosphorylation, methylation of lysine or arginine side chains, and the acetylation of lysine side chains. These are often involved in the regulation of biological processes. Amino acids containing stable heavy isotopes are used to label peptides in mass spectra studies.
Cyclization
Cyclization of peptides enhances conformational stability, can mimic protein secondary structures and enhance protease stability. Cyclization can be achieved in a number of different ways – by disulfide bond formation between cysteine residues, by head-to-tail amide bond formation, by ring-closing metathesis (stapling), or by amide bond formation between side chains or a side chain and the N- or C-terminal of the peptide.
Additional Services
AAPPTec can provide the following services for an additional fee.
- Amino Acid Analysis
- Aliquoting
- TFA Removal
Large Scale Custom Peptide Production
We can perform custom peptide synthesis in larger scales, from gram to multi-kilogram quantities. AAPPTec complies with the most stringent quality control specifications at a competitive price. Let our experienced chemists assist with your development and production needs. All requests are evaluated with strict confidentiality.
From our extensive experience in custom peptide synthesis, to our well-trained technical team and highest production standards, we hope to be your strong and reliable partner in the life sciences industry.
SARS-CoV-2 Research Peptides
Research world-wide is focusing on researching and developing vaccines and treatments for the SARS- CoV-2 virus. The binding of the virus spike protein to ACE-2 appears to be a key step in infecting cells, therefore much of the current research is focused on this interaction. These are some of the peptides that are of interest in the SARS-CoV-2 research.
(Biotin – Ahx) – SARS – CoV – 2 Spike RBM (receptor binding motif)
Biotin-Ahx-SNNLDSKVGGNYNYLYRLFRK
Wan Y, Shang J, et al. Receptor recognition by the novel coronavirus from Wuhan: an analysis based on decade-long structural studies of SARS coronavirus. J Virol. 2020;94(7). Doi: 10.1128/JVI.00127-20
Chen Y, et al. Structure analysis of the receptor binding of 2019-nCoV. Biochem Biophys Res Commun. 2020; 525(1), p135-134. Doi: 10.1016/j.bbrc.2020.02.071
SARS – CoV – 2 Spike RBD (receptor binding domain), 319 – 335
RVQPTESIVRFPNITNL
Yoya Vashi, Vipin Jagrit , Sachin Kumar, Understanding the B and T cells epitopes of spike protein of severe respiratory syndrome 2 coronavirus-A computational way to predict the immunogens bioRxiv preprint doi: 10.1101/2020.04.08.013516.
Spike-binding peptide 1
IEEQAKTFLDKFNHEAEDLFYQS
This peptide specifically binds the SARS-CoV-2 receptor binding domain with low nano-molar efficiency,
G. Zhang, S. Pomplun, A. R. Loftis, A. Loas, and B. L. Pentelute, bioRxiv preprint doi: https://doi.org/10.1101/2020.03.19.999318
SFS-3249-v
Dabcyl-Lys-Thr-Ser-Ala-Val-Leu-Gln-Ser-Gly-Phe-Arg-Lys-Met-Glu(Edans)-NH2 SARS-CoV/SARS-CoV-2 main protease substrate (fluorogenic).
C.J. Kuoet al., Biochem. Biophys. Res. Commun., 2004, 318, 862. Doi: 10.1016/j.bbrc.2004.04.098
L. Zhang, et al., Science, eabb3405 (2020). DOI: 10.1126/science.abb3405
S. Jo et al., J Enzyme Inhib Med Chem, , 2020, 35(1), 145. Doi: 10.1080/14756366.2019.1690480
W. Rut, et al., bioRxiv, (2020). (pre-print) DOI: 10.1101/2020.03.07.981928
Angiotensin I Converting Enzyme 2, (ACE – 2) Substrate
Mca-APK(Dnp)
Eduardo Carrera, Andrea Linares, Arline Joachim, Malaika Jean-Baptiste, Robert Speth , MCA-APK(Dnp) is not a selective substrate of angiotensin-converting enzyme-2, The FASEB Journal 2014 28:1_supplement
DX 600, ACE2 Inhibitor
Ac-GDYSHCSPLRYYPWWKCTYPDPEGGG-NH2
Huang, L., Sexton, D.J., Skogerson, K., et al. Novel peptide inhibitors of angiotensin-converting enzyme
2. J. Biol. Chem. , 2003, 278(18), 15532-15540. doi:10.1074/jbc.M212934200
Joshi, S., Balasubramanian, N., Vasam, G., et al. Angiotensin converting enzyme versus angiotensin converting enzyme-2 selectivity of MLN-4760 and DX600 in human and murine bone marrow-derived
cells. Eur. J. Pharmacol., 2016, 774, 25-33. Doi: 10.1016/j.ejphar.2016.01.007
Custom Peptide Libraries
AAPPTec can incorporate most standard peptide modifications within custom peptide libraries. Standard modifications that can be incorporated are unusual amino acids, D-amino acids, C-terminal amidation, N-terminal modification, and biotin, dye or fluorescence labeling on the N-terminal or lysine side chains.
Custom libraries are typically completed in 2-3 weeks. Typical delivery consists of lyophilized peptides in 96-well titer plates, peptide location table, and MS and HPLC data. For a quotation, please complete our quotation form and in the comment box state that you are requesting a quotation on a peptide library.
Custom Peptide Providers
AAPPTec has unique experience in producing custom peptides. When there were only three companies in the United States providing custom peptides in the 1980’s, one of them was Dr. Hossain Saneii, the founder of AAPPTec. AAPPTec provides not only custom peptides but also automated peptide synthesizers ranging from small scale to large scale production, so it is not difficult for AAPPTec to provide highly competitive pricing for high quality peptides. AAPPTec has designed and installed production facilities to produce peptides in up to 50-kilogram reactors. From a few milligrams to multi-kilograms, AAPPTec can provide high quality custom peptides at a very competitive price.
AAPPTec combines exceptional quality and characterization with extremely competitive pricing, and they often deliver peptides even more pure than we requested. I strongly recommend their custom synthesis service to colleagues who don’t have the time, expertise, or equipment to make and characterize their own peptides.-A Researcher from University of Pennsylvania
Custom Peptide Synthesis
AAPPTec custom peptide synthesis and peptide libraries are offered from 2 to 120 amino acids to include modifications of standard peptide structures, including phosphorylation, methylation, labeling with tags or dyes, cyclization, conjugation with PEG, and incorporation of D-amino acids. AAPPTec custom peptide synthesis can provide custom peptides as trifluoroacetic acid (TFA) salts, acetate salts or hydrochloride salts. AAPPTec custom peptide synthesis has been used in proteomics, antibody products, lead discovery in drug development, etc. AAPPTec peptide chemists help you design and synthesize reliable and validated custom peptides.
AAPPTec custom peptide synthesis services provide custom peptides in several purity levels. Typical purity levels are:
1. Immunological Grade (suitable for forming polyclonal antibodies)
2. 80% or greater (tissue culture; ligand for affinity purification; non-quantitative antibody blocking experiments)
3. 90% or greater (in vivo studies; bioassays; markers for electrophoresis; monoclonal antibodies)
4. 95% or greater (ELISA; RIA; enzyme substrate)
5. 98% (NMR; chromatography standards)
In selecting a custom peptide synthesis company, factors to consider in addition to cost are accuracy, success rate and speed of delivery.
Our peptides are available in all scales, from milligram research scale to multi-kilogram production scale. We provide single custom peptides, multiple peptides and custom peptide libraries in a timely manner at competitive prices.
AAPPTec’s experienced peptide chemists quickly and efficiently prepare most peptide sequences. Custom peptide synthesis is AAPPTec’s specialty.
Our chemists have experience and expertise in preparing long peptides in high purity. For example, AAPPTec has synthesized and delivered 78 to 81 amino acid custom peptides at 95% purity.
During each custom peptide synthesis, AAPPTec chemists utilize UV monitoring and in-process tests, such as the Kaiser test, to assure each synthesis step is complete before proceeding with the synthesis. If necessary, double coupling protocols are used to assure complete coupling. In addition, heating may be utilized to accelerate slow or difficult reactions. By assuring complete coupling of each amino acid, AAPPTec chemists maximize overall yield, minimize impurities and reduce the amount of purification required for each custom peptide.
In custom peptides containing hydrophobic sequences where hydrogen bonding of the peptide backbone can result in slow or incomplete reactions, AAPPTec chemists may utilize hydrogen-bond disrupting elements such as pseudoprolines or Dmb-protected amino acids. In some cases, Boc chemistry with in situ neutralization affords higher yields than Fmoc chemistry.
AAPPTec chemists take steps to minimize racemization of the activated amino acid in coupling which leads to undesired diasteromeic peptides. Racemization during activation is minimized by activating the amino acid residue at reduced temperature and adding HOBt which suppresses the rate of racemization. Cysteine and histidine are especially prone to racemization with uronium activating reagents. When racemization of these residues is especially troublesome, AAPPTec chemists may use carbodiimide/HOBt activation which results in lower levels of racemization.
All custom peptide products are provided with a complete quality control package, including HPLC and Mass Spectral Analysis, to confirm the purity and identity of the peptide. From 2 amino acids to 85 amino acids, AAPPTec can prepare peptides in the scale and purity required. We comply with the most stringent quality control specifications for a reasonable price.
Custom Peptide Prices
Our custom peptide prices are determined mainly by three factors: the amount of peptide, the length of the peptide sequence and the amount of purification required. For standard peptides, the purification costs may be a significant part of the custom peptide price. Thus crude peptides are relatively inexpensive, while 95% pure peptides have higher prices than 85% pure peptides. AAPPTec minimizes custom peptide prices by utilizing peptide synthesis protocols that produce crude peptides with high purity, thus reducing the purification costs.
Peptide prices will depend on the purity and quantitity of peptide required. Longer peptides may be more difficult to synthesize due to hydrogen bonding between peptide chains and other factors. Peptides containing 30 amino acids or more and peptides with modifications require special quotations.
To minimize the cost of custom peptides, do not request peptide purity greater than is necessary for your application. The table below lists recommended peptide purities for various applications.
AAPPTec Custom Peptide Purity Levels
Immunological Grade: suitable for forming polyclonal antibodies
80% or Greater: tissue culture; ligand for affinity purification; non-quantitative antibody blocking experiments
90% or Greater: in vivo studies; bioassays; markers for electrophoresis; monoclonal antibodies
95% or Greater: ELISA; RIA; enzyme substrate
98%: NMR; chromatography standards
Custom Peptide Quotations and Ordering
To request a quotation on custom peptide synthesis, use our on-line quote request form or email your peptide sequence, quantity and purity requirements to sales@aapptec.com and put “Custom Peptide Synthesis” in the subject line. Your information will be held in strict confidence.
- All peptides are TFA salt unless it is specified otherwise in the customer’s PO. All custom peptides are peptide salts.
- All peptides are sold only for experimental research, not for use in humans.
- Customer must verify the sequence in the sales order and their PO; AAPPTec is not responsible for mistakes in the sequence or any biological activity
- Custom peptides can not be returned.
SARS-CoV-2 Research Peptides
Research world-wide is focusing on researching and developing vaccines and treatments for the SARS- CoV-2 virus. The binding of the virus spike protein to ACE-2 appears to be a key step in infecting cells, therefore much of the current research is focused on this interaction. These are some of the peptides that are of interest in the SARS-CoV-2 research.
(Biotin – Ahx) – SARS – CoV – 2 Spike RBM (receptor binding motif)
Biotin-Ahx-SNNLDSKVGGNYNYLYRLFRK
Wan Y, Shang J, et al. Receptor recognition by the novel coronavirus from Wuhan: an analysis based on decade-long structural studies of SARS coronavirus. J Virol. 2020;94(7). Doi: 10.1128/JVI.00127-20
Chen Y, et al. Structure analysis of the receptor binding of 2019-nCoV. Biochem Biophys Res Commun. 2020; 525(1), p135-134. Doi: 10.1016/j.bbrc.2020.02.071
SARS – CoV – 2 Spike RBD (receptor binding domain), 319 – 335
RVQPTESIVRFPNITNL
Yoya Vashi, Vipin Jagrit , Sachin Kumar, Understanding the B and T cells epitopes of spike protein of severe respiratory syndrome 2 coronavirus-A computational way to predict the immunogens bioRxiv preprint doi: 10.1101/2020.04.08.013516.
Spike-binding peptide 1
IEEQAKTFLDKFNHEAEDLFYQS
This peptide specifically binds the SARS-CoV-2 receptor binding domain with low nano-molar efficiency,
G. Zhang, S. Pomplun, A. R. Loftis, A. Loas, and B. L. Pentelute, bioRxiv preprint doi: https://doi.org/10.1101/2020.03.19.999318
SFS-3249-v
Dabcyl-Lys-Thr-Ser-Ala-Val-Leu-Gln-Ser-Gly-Phe-Arg-Lys-Met-Glu(Edans)-NH2 SARS-CoV/SARS-CoV-2 main protease substrate (fluorogenic).
C.J. Kuoet al., Biochem. Biophys. Res. Commun., 2004, 318, 862. Doi: 10.1016/j.bbrc.2004.04.098
L. Zhang, et al., Science, eabb3405 (2020). DOI: 10.1126/science.abb3405
S. Jo et al., J Enzyme Inhib Med Chem, , 2020, 35(1), 145. Doi: 10.1080/14756366.2019.1690480
W. Rut, et al., bioRxiv, (2020). (pre-print) DOI: 10.1101/2020.03.07.981928
Angiotensin I Converting Enzyme 2, (ACE – 2) Substrate
Mca-APK(Dnp)
Eduardo Carrera, Andrea Linares, Arline Joachim, Malaika Jean-Baptiste, Robert Speth , MCA-APK(Dnp) is not a selective substrate of angiotensin-converting enzyme-2, The FASEB Journal 2014 28:1_supplement
DX 600, ACE2 Inhibitor
Ac-GDYSHCSPLRYYPWWKCTYPDPEGGG-NH2
Huang, L., Sexton, D.J., Skogerson, K., et al. Novel peptide inhibitors of angiotensin-converting enzyme
2. J. Biol. Chem. , 2003, 278(18), 15532-15540. doi:10.1074/jbc.M212934200
Joshi, S., Balasubramanian, N., Vasam, G., et al. Angiotensin converting enzyme versus angiotensin converting enzyme-2 selectivity of MLN-4760 and DX600 in human and murine bone marrow-derived
cells. Eur. J. Pharmacol., 2016, 774, 25-33. Doi: 10.1016/j.ejphar.2016.01.007
Peptide Synthesis Services
Peptide synthesis services that AAPPTec provides include incorporation of non-standard amino acids, modifications at the N-terminal, C-terminal or side chains, and the formation of cyclic structures. Non-standard amino acids can usually be incorporated into a peptide synthesis with little difficulty. Highly expensive building block, such as isotope-labeled amino acids, are incorporated most efficiently and cost effectively near the N-terminal.
N-Terminal Peptide Modifications
N-terminal modifications are made for a variety of purposes. Some modifications improve the stability of the peptide to proteolytic enzymes or improve the absorption and bioavailability of the peptide. Other N-terminal modifications introduce a dye or tag that allows areas where the peptide accumulates to be visualized. Some modifications are immunoadjuncts to enhance antibody production or linkers to allow conjugation of the peptide to other biomolecules.
C-Terminal Peptide Modifications
C-terminal modifications, except for amidation, are less common. They are incorporated either through the utilization of special resins or solution phase reactions after cleavage from the resin. C-terminal modifications can improve the stability of the peptide or alter its interaction with receptors. C-terminal modifications are also used to produce substrates used in enzymatic studies.
Internal Modifications
Internal modifications are incorporated into synthetic peptides by using unusual or specially derivatized amino acids. Some internal modifications, such as D-amino acids, beta-amino acids, and N-methyl amino acids, improve peptide stability to enzymes. Unusual amino acid modifications are often used to optimize peptide binding and selectivity in binding to target molecules or insertion into membranes.. Some internal modifications correspond to post translational modifications in proteins. Some examples are phosphorylation, methylation of lysine or arginine side chains, and the acetylation of lysine side chains. These are often involved in the regulation of biological processes. Amino acids containing stable heavy isotopes are used to label peptides in mass spectra studies.
Cyclization
Cyclization of peptides enhances conformational stability, can mimic protein secondary structures and enhance protease stability. Cyclization can be achieved in a number of different ways – by disulfide bond formation between cysteine residues, by head-to-tail amide bond formation, by ring-closing metathesis (stapling), or by amide bond formation between side chains or a side chain and the N- or C-terminal of the peptide.
Additional Services
AAPPTec can provide the following services for an additional fee.
- Amino Acid Analysis
- Aliquoting
- TFA Removal
Large Scale Custom Peptide Production
We can perform custom peptide synthesis in larger scales, from gram to multi-kilogram quantities. AAPPTec complies with the most stringent quality control specifications at a competitive price. Let our experienced chemists assist with your development and production needs. All requests are evaluated with strict confidentiality.
From our extensive experience in custom peptide synthesis, to our well-trained technical team and highest production standards, we hope to be your strong and reliable partner in the life sciences industry.
Custom Peptide Libraries
AAPPTec can incorporate most standard peptide modifications within custom peptide libraries. Standard modifications that can be incorporated are unusual amino acids, D-amino acids, C-terminal amidation, N-terminal modification, and biotin, dye or fluorescence labeling on the N-terminal or lysine side chains.
Custom libraries are typically completed in 2-3 weeks. Typical delivery consists of lyophilized peptides in 96-well titer plates, peptide location table, and MS and HPLC data. For a quotation, please complete our quotation form and in the comment box state that you are requesting a quotation on a peptide library.
Custom Peptide Providers
AAPPTec has unique experience in producing custom peptides. When there were only three companies in the United States providing custom peptides in the 1980’s, one of them was Dr. Hossain Saneii, the founder of AAPPTec. AAPPTec provides not only custom peptides but also automated peptide synthesizers ranging from small scale to large scale production, so it is not difficult for AAPPTec to provide highly competitive pricing for high quality peptides. AAPPTec has designed and installed production facilities to produce peptides in up to 50-kilogram reactors. From a few milligrams to multi-kilograms, AAPPTec can provide high quality custom peptides at a very competitive price.
List of Other Custom Peptide Providers
AAPPTec combines exceptional quality and characterization with extremely competitive pricing, and they often deliver peptides even more pure than we requested. I strongly recommend their custom synthesis service to colleagues who don’t have the time, expertise, or equipment to make and characterize their own peptides.-A Researcher from University of Pennsylvania
