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GHK-Cu (glycyl-L-histidyl-L-lysine–copper) is an endogenous tripeptide–copper complex present in plasma and tissue fluids, with circulating levels declining markedly with age. While its role is long-established in wound healing, GHK-Cu has been shown to modulate extracellular matrix synthesis, lower inflammatory responses, and promote survival of stem and progenitor cells. Further, controlled ex vivo human skin and fibroblast models, and in vivo animal injury studies, were used to characterize its potential for anti-aging and healing. Across multiple studies, GHK-Cu showed increases in type I/III collagen and elastin deposition, downregulated matrix metalloproteinases (MMP’s), and enhanced glycosaminoglycan content—changes consistent with ECM rejuvenation. Recent innovations in hydrogel delivery systems have buoyed these effects. Specifically, GHK-Cu greatly helped with wound closure, enhanced vascularization, and reduced inflammatory and oxidative markers. These findings position GHK-Cu as an effective tool in wound healing, age-related degeneration, and regenerative medicine.

Historically peptide synthesis has been limited in the sequence length of compounds generated due to multiple factors, including low synthetic yields, crude mixture complexity, and purification difficulty of closely eluting, sequence similar contaminants. Recent advances in both the synthetic and analytical chemistry spaces have pushed this length beyond what was previously thought possible. While the syntheses improve, the purification stage has struggled to keep pace with growing synthetic capacity. This gap is magnified by the growth of AI based research pipelines, as the number of sequences to be transferred from in-silico to in-vitro for testing has increased dramatically. Improvements in automation have allowed purification teams to keep pace with synthetic teams for short peptides (usually <30 amino acids), but as peptide length increases so does purification complexity. Here we describe the adaptation of a high-throughput small molecule library purification methodology to peptide purification, moving from standard libraries of 10-12mers to beyond 70 amino acids in length while maintaining the same throughput as previous small molecule studies. This method leverages advancements in mass spectrometry, resin chemistry, and automation to enable the production of higher quality libraries of larger peptide molecules without sacrificing speed.

Sponsored Talk #4
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Dominik Sarma
Senior Market Manager, Gyros Protein Technologies

Simplified catch-and-release protocol transforms difficult-to-dissolve peptides into routine purifications

Abstract

Peptide purification remains the primary bottleneck in peptide production, despite significant advances in chemical synthesis technology. While HPLC (High-pressure Liquid Chromatography) continues to dominate, complementary purification methods are urgently needed. We present PEC (PurePep® EasyClean) 2.0, an enhanced catch-and-release purification protocol that eliminates the precipitation step after TFA (trifluoroacetic acid) cleavage from the SPPS (solid-phase peptide synthesis) resin, thereby addressing critical workflow inefficiencies associated with traditional methods, particularly for peptides that are difficult to dissolve.
The original PEC protocol required ether precipitation post-cleavage from the SPPS resin, introducing ether-derived aldehyde and ketone contaminations that interfered with the catch-and-release linker chemistry.[1-2] Additionally, precipitation and redissolution steps presented significant challenges for hydrophobic peptides, resulting in material loss and extended processing times.
Building on novel TFA-stable purification beads and findings by Mthembu et al. [3] demonstrating superior performance of thiol-free cleavage cocktails in suppressing back-alkylation, we developed PEC 2.0. This innovation enables direct purification from the TFA cleavage cocktail, as the absence of thiol scavengers prevents interference with the aldehyde-functionalized purification resin. The protocol leverages the TFA cocktail as an optimal peptide solvent, eliminating dissolution challenges.
Our results demonstrate comparable or superior purities and yields compared to previous protocols, with exceptional performance for hydrophobic peptides. The streamlined workflow reduces processing time and standardizes procedures across diverse peptide sequences.
This novel catch-and-release methodology represents a significant advancement in peptide purification technology. By providing a robust alternative to conventional methods that bridges synthesis and purification workflows without intermediate precipitation, PEC 2.0 addresses longstanding challenges in peptide production. The simplified protocol enables researchers to tackle increasingly complex peptide targets while maintaining high throughput and scalability, ultimately accelerating peptide drug development and research applications.
[1] J. Pept. Sci. 2018, 15, e3136
[2] Chem. Sci. 2021, 12, 2389-2396
[3] Org. Process Res. Dev. 2025, 29, 3, 691–703

Bio

Dominik Sarma is a peptide industry professional with a Ph.D. in organic chemistry from Berlin's Humboldt University. In 2018, he co-founded Belyntic with three partners, developing the Peptide Easy Clean (PEC) technology for peptide purification. As co-CEO and head of communications, Sarma helped secure Belyntic's acquisition by Gyros Protein Technologies in 2022. He then joined Gyros as Senior Market Manager, leading strategic market development for their peptide business since late 2022.

Glucagon Like Peptide (GLP-1) can be used in treatments of diabetes type 2, where carbohydrates are not metabolized due to insulin resistance or lack of insulin, resulting in high level of glucose in the blood. The approval of the GLP-1 receptor agonist semaglutide for weight regulation in January 2023 ushered in a new era of obesity therapy. According to Frost & Sullivan survey, the GLP-1 drug market is expected to reach US$28.3 billion in 2025, with an annual growth rate of 16.6% from 2020 to 2025, and will exceed US$40 billion in 2030.
Silica reversed phase chromatography (RPC) is a popular purification tool for peptide-based therapeutics such as insulins and GLP-1 compounds. As GLP-1 drug market grows, there is a big demand for bulk media with high performance and much longer lifetime for purification of peptide-based drugs.
NanoMicro Technology is the only company to commercialize monodispersed silica bulk media for separation and purification process. Our innovative technology allows us to manufacture monodispersed silica particles in large quantity (several hundred kilograms a batch with almost 100% yield), thus dramatically reduces cost and meets high demands of purification process market needs. In this report, we would like to introduce our UniSil Revo 10-100 particles, discuss their physical properties and chemical stability, and show their applications in purification of insulin and GLP-1. With an inert surface coating, we have achieved lifetime of UniSil Revo 10-100 at least 2-3x better than silica particles at 0.1M NaOH flash condition. With pore size of 100Å, UniSil Revo 10-100 particles have very similar selectivity and retention time to Kromasil 100 particles, making direct replacement of Kromasil 100 very feasible, without changing of purification methods, or sacrificing yields and purity of GLP-1 drugs.

We have developed streaMLine, an innovative platform for peptide drug discovery that greatly shortens the time from initial hit to clinical drug candidate. The platform allows for high-throughput synthesis and screening. Thousands of peptides are systematically screened in in vitro assays and on physicochemical parameters, whereby the streaMLine platform enables complete sequence exploration and simultaneous optimization of key parameters.
We employ a fully digitalized laboratory system where detailed information on all aspects of sample lifetime is tracked. Using a machine learning approach, this enables accurate distinction of key chemical peptide modifications from artefact background effects. This unique strategy for peptide screening integrates with state-of-the-art in vivo pharmacology facilities, including advanced animal models and rapid determination of PK/PD relationships.
Using the streaMLine platform, we developed novel GLP-1R agonists, to demonstrate how high-throughput screening peptide libraries and machine learning guided drug design can be applied to accelerate drug discovery. We systematically synthesized and screened a total of 2,688 peptides in a parallelized optimization workflow. Using this approach, we identified a vast chemical solution space for generating novel GLP-1R agonists based on an alternative peptide starting point, i.e. the secretin backbone. To validate the pipeline, we conducted an in-depth profiling of a GLP-1R agonist that showed high receptor selectivity, attractive physicochemical properties, a potent weight-lowering in vivo efficacy, and a pharmacokinetic profile compatible with a once-weekly human dosing regimen.

Sponsored Talk by CPC Scientific
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John Phipps
VP of Clinical Pipeline Development, CPC Scientific

Reduction in Impurities Formed During Large-Scale Semaglutide Synthesis

Abstract

Semaglutide, a member of the GLP-1 class of anti-diabetic drugs, has received widespread attention in recent years due to its development as a treatment for obesity. While the current commercial supply utilizes recombinant DNA manufacturing technology, synthetic methods employing solid phase peptide synthesis (SPPS) and/or convergent peptide synthesis have been developed to produce a generic version of semaglutide. However, the non-enzymatic approach can result in poor product quality and low yields that stymie innovation and development.

To address this, CPC Scientific have designed and used the novel compound Fmoc-Gly-OtBu-FMPB that functions as a linker to AM resin and contains the C-terminal Gly31 required in semaglutide. This innovative approach suppresses formation of impurities, most notably those derived through formation of endo-Gly31-semaglutide. Through use of this novel linker and a convergent fragment-based approach, the purity of semaglutide peptide has been increased to 99.5% when preparing multiple-kilogram batches of the final API.

Bio

John Phipps serves as the Vice President of Clinical Pipeline Development at CPC Scientific, boasting an extensive and distinguished track record in the pharmaceutical sector. His expertise spans biotechnology, chemistry, technology transfer, drug discovery, and protein chemistry, underpinned by a Bachelor of Science in Biochemistry from Colorado State University. John began his career in 1992 as a bench chemist and manager of the Colorado State University core facility from 1999 – 2001, making peptides by SPPS using Boc and Fmoc chemistry. In 2001, John founded Global Peptide Services, serving as president from 2001 to 2008. In 2010, he worked at Bachem as a business development manager until 2017. John joined to CPC Scientific in 2017, and he currently resides in Long Beach, California, and is available to engage peptide and oligonucleotide clients throughout the United States.

The insulin/IGF-1 signaling axis regulates cell metabolism and growth, and its dysregulation is implicated in several diseases, including cancer. Elevated IGF-1 levels and IGF1R overexpression drive tumor proliferation, survival, and therapy resistance. While IGF1R is a promising oncology target, selective inhibition remains challenging due to structural homology with the insulin receptor (IR). Existing IGF1R inhibitors lack specificity and cause hyperglycemia by inhibiting IR signaling.
Our lab recently identified viral insulin/IGF1-like peptides (VILPs), a novel protein family encoded by Iridoviridae viruses, sharing ~30–50% identity with human insulin and IGF-1. Chemically synthesized VILPs bind both IR and IGF1R, with most acting as agonists. Remarkably, VILPs from Mandarin fish ranavirus (MFRV) and Lymphocystis disease virus-1 (LCDV1) function as natural IGF1R-selective antagonists, sparing the IR.
Preliminary studies using chimeric VILPs demonstrate that the LCDV1-VILP C-domain and a Gly8>Ser substitution in the B-domain convert IGF-1 into an IGF1R antagonist; reversing these changes abolishes antagonism. To further define structural features driving antagonism, we are engineering IGF-1/MFRV-VILP chimeras and mutating five conserved residues shared among antagonistic VILPs. Candidate peptides will be screened in IGF1R-overexpressing murine embryonic fibroblasts to assess effects on receptor autophosphorylation and Akt/Erk signaling. Promising hits will advance to recombinant production and detailed analysis of IGF1R versus IR selectivity.
This platform provides a rational path to designing next-generation IGF1R antagonists with minimal IR cross-reactivity, addressing a critical limitation of current therapies and offering a novel therapeutic avenue for IGF1R-driven diseases.

Infectious diseases remain a major public health threat, with limited therapeutic options available for several pathogens, including multidrug-resistant Pseudomonas aeruginosa. To address this challenge, we have developed a novel approach using bifunctional molecules (chimeras) that recruit complement protein C3 and activate the immune system to eliminate infections. C3 is a highly abundant plasma protein (5–13 µM) and a central component of all three major pathways of the innate immune system: the classical pathway, alternative pathway, and lectin pathway. Deposition of C3 on the bacterial surface initiates a complement activation cascade, leading to bacterial clearance via multiple mechanisms, including membrane lysis by the membrane attack complex and immune cell recruitment through opsonization.
To identify C3 binders, we screened several DNA-encoded libraries and discovered hits with low micromolar affinity for C3. The hits were validated using surface plasmon resonance (SPR) and STD-NMR. Incorporating proprietary lysine-targeting handles into the hit structures enabled chemoproteomic analysis, which localized the binding site near Lys678 of C3. Subsequent medicinal chemistry optimization yielded binders with varying affinities. Conjugating these C3 binders to bacterial-targeting peptides produced bifunctional molecules (chimeras) capable of inducing C3 deposition on the P. aeruginosa membrane and inhibiting bacterial growth at sub-micromolar concentrations. This effect was shown to be dependent on both complement-active serum and the C3-binding moiety. Our lead chimera demonstrates favorable pharmacological properties, including good aqueous solubility, plasma stability, moderate microsomal stability, no hemolysis at 2 µM, and no cytotoxicity in mammalian cells at 10 µM. Pharmacokinetic studies in mice reveal an in vivo half-life of approximately 5 hours and efficient accumulation in lung tissue. In murine lung infection models using both carbapenem-sensitive (ATCC27853) and -resistant (AR #0246) P. aeruginosa strains, treatment with our lead compound at 29 µmol/kg (BID) resulted in a robust 2-log reduction in bacterial load. The complement-recruiting chimera platform is now being expanded to target other pathogens and holds promise in the fight against antimicrobial resistance.

Protein modification alters structure and reactivity by adding non-native groups to specific residues. For most nucleophilic residues, multiple functionalization methods have been reported. However, there are limited methods that take advantage of the unique reactivity of methionine residues. We exploited this reactivity profile of methionine by using a strained reactive intermediate selective for thioethers. To optimize the reaction in aqueous conditions, we altered the structure of the reactive intermediates’ precursors to increase their solubility in water, while preserving reactivity. We show that these reactive intermediates can be generated under mild conditions allowing for the preservation of peptide and protein structures. The strategy was successfully applied to a variety of natural products, peptides, and proteins. Additionally, we demonstrated the one-pot sulfonium formation then demethylation, which afforded the functionalized homocysteine product. The development of this site-selective method towards methionine will allow for valuable modifications of complex molecules in mild conditions.