FAQs 2017-12-21T11:34:51-06:00
What is Group Assisted Purification (GAP) Chemistry? 2021-03-17T11:32:27-05:00

In recent years the Dr. Guigen Li Research Group and others have made significant advancements in the area of purification chemistry, focusing specifically on avoiding column chromatography and recrystallization.

This research and concept have been defined as Group-Assisted Purification (GAP) chemistry/technology as follows: “a chemistry for organic synthesis that avoids traditional purification methods such as chromatography and/or recrystallization by purposefully introducing a well-functionalized group in the starting material or in the newly generated product.

How are GAP peptides shipped? What data will be provided with my order? 2018-09-17T17:12:18-05:00

Research grade peptides will be shipped lyophilized in small polypropylene vials (2 ml or 10ml) with screw caps. Shipment packing material includes freezer packs and protective padding to avoid damage to the product while in transit. All product tubes contain labels with information on primary sequence, amount, and batch number.  We provide all customers with a detailed Certificate of Analysis (CoA) which includes MALDI-TOF and/or ESI HRMS to confirm identity of the product delivered.

How long does it take from start to finish? 2018-09-17T17:21:46-05:00

In most cases, GAP-PS research and production is defined under an MSA and SOW.  The potential upsides of research include discovery of new pathways for using GAPP’s technology to deliver high peptide yields and easy scale up; flexibility in protecting group strategies; utilizing green chemistry and lowering solvent waste; and delivering high crude-purity peptides which may result in reduction of column time and reduction of overall peptide synthesis cost.  Research can be unpredictable but research timelines can be shortened if the client provides known literature or procedures for their existing synthetic routes.  

What is GAP Peptide Synthesis (GAP-PS)? 2022-09-26T14:55:52-05:00

The synthesis of peptides using Group Assisted Purification Peptide Synthesis (GAP-PS) resembles solid-phase peptide synthesis,  but our process runs in solution. By running the coupling reaction in solution phase and purifying by simple filtration and/or extraction, GAP Peptide Synthesis combines the advantages of both LPPS and SPPS techniques. Purification for the GAP-PS process is facilitated by a small anchor molecule which controls solubility during an aqueous liquid extraction process.  The uniquely designed anchor molecule replaces resin beads used in solid-phase peptide synthesis (SPPS). GAP-PS uses standard Fmoc amino acid derivatives found in SPPS. Coupling and deprotection of the Fmoc protecting groups are performed in solution and allow for fast cycle times and direct in-process controls. Excess reagents as well as reaction related by-products are removed by aqueous extractions. Intermediate isolation of the protected peptide and excessive washing steps are not required when using the GAP-PS approach.  The process requires no special equipment.

GAP Peptide Synthesis is highly amenable to Fmoc chemistry, but it can also handle Cbz and Boc protection strategies. Because our proprietary GAP Groups function chemically as just another protecting group, all chemistries are amenable to our method. This includes carbodiimide, uronium, ammonium, and other coupling reagents, including Oxyma based products.

GAP-PS  addresses the key challenges manufacturers are facing:  lowering CoGS, improving quality controls, reducing hazardous waste, and improving the environmental impact resulting from peptide synthesis.  GAP-PS offers easy scalability, high process efficiency, and greener manufacturing options. Solvent consumption and material requirements are significantly reduced compared to legacy methods. GAP-PS also avoids the use of solvents and reagents which are carcinogenic, mutagenic, or toxic to reproduction (CMR substances).

Does GAP Peptides provide peptide modifications? 2018-01-11T12:27:37-06:00

GAP Peptides can provide a variety of well-established peptide modifications like acetylation, biotinylation, phosphorylation, and attachment of fluorescent dyes or quencher pairs.  We also provide synthesis services for unusual reactions.   To discuss special needs in detail – please call or email for more information.

What volume is GAP Peptides, LLC able to synthesize? 2020-09-11T13:33:58-05:00

GAP Peptides, LLC currently has in-house capacity to synthesize custom peptides from the g to hundreds-of-grams scale.  Providing mg scale is also possible for sample purposes.  Process advantages and tangible benefits delivered increase at larger scales; contact us to discuss synthesis of larger volumes.

Is there any limit to the length of peptide that can be synthesized? 2022-09-26T14:57:17-05:00

GAP Peptides currently offers custom research services for peptides ranging from two to twenty-nine amino acids in length. Recent research progress has shown our process enables efficient production of most of the peptides in range from three to twenty-two amino acids in length; however, ongoing research aims to target peptide chains ranging up to thirty-two amino acids and beyond.

For longer peptides the synthesis efficiency success rate drops; therefore in the case of research conducted on longer length targets, recombinant technologies might be used depending on peptide application.

How does GAP Peptides insure the quality and purity of peptides produced? 2020-09-16T09:04:27-05:00

Custom research peptides made by GAP Peptides will be analyzed by HPLC and MS.   In addition to MALDI-MS, our routine quality control testing includes HPLC-MS techniques to guarantee that a single peak is visible in the HPLC profile corresponding to the target mass.

Since peptides show different ion response depending on the actual primary sequence, availability of different MS-equipment is crucial for quality-assured analysis. We use state of the art equipment [MALDI-MS, HPLC-(ESI)MS (ion trap and quadrupole)] which guarantees unambiguous analysis and a reliable product.

A Certificate of Analysis (CoA), and other analytical data as requested and produced during the research effort, accompanies each peptide order shipped.