Tirzepatide (TIRZ) Peptide

Tirzepatide is a first-in-class 39-amino acid dual agonist peptide targeting both the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. With a molecular formula of C₂₂₅H₃₄₈N₄₈O₆₈ and molecular weight of 4813.45 g/mol (CAS 2023788-19-2), it represents the first "twincretin" to enter clinical development. It has been studied in the SURPASS and comparative trial clinical trial programs. AminoCore Research provides Tirzepatide exclusively for research purposes.

The term "twincretin" refers to Tirzepatide's ability to simultaneously activate two incretin hormone receptors — GIP and GLP-1. While selective GLP-1 receptor agonists target only one pathway, Tirzepatide engages both incretin systems to produce synergistic metabolic effects. In vitro, it shows preferential GIP receptor affinity (EC₅₀ 0.135 nM) over GLP-1 receptor (EC₅₀ 13.3 nM). This dual mechanism was shown in the SURPASS-2 trial to produce superior glycemic and weight outcomes versus selective GLP-1R agonism with GLP-1 agonist peptide.

Tirzepatide has been evaluated in extensive clinical programs: the SURPASS series (type 2 glycemic homeostasis research, including SURPASS-1 through 5 and SURPASS-CVOT) and the comparative trial series (weight management). In SURPASS-2, Tirzepatide demonstrated superior HbA1c and metabolic regulation researchs versus GLP-1 agonist peptide 1.0 mg. In comparative trial-1, the 15 mg dose produced 20.9% mean body metabolic regulation research at 72 weeks. The FDA approved Tirzepatide for type 2 glycemic homeostasis research (2022) and weight management (2023) based on evidence from over 7,700 trial participants.

Store lyophilized Tirzepatide at -20°C in a sealed container protected from light and moisture for up to 24 months of stability. After reconstitution, store at 2-8°C and use within 28 days. For extended storage of reconstituted peptide, prepare single-use aliquots in low-bind tubes and freeze at -20°C. Minimize freeze-thaw cycles to preserve peptide integrity and biological activity.

AminoCore Research provides Tirzepatide at ≥99% purity verified by HPLC analysis. Each vial is accompanied by a Certificate of Analysis (COA) documenting purity testing, identity confirmation, and analytical data for research quality assurance.

Reconstitute Tirzepatide lyophilized powder using sterile bacteriostatic water or PBS (pH 7.4). Allow the vial to equilibrate to room temperature, inject diluent slowly along the vial wall, and gently swirl until dissolved. The solution should be clear and colorless to slightly yellow. Use low-protein-binding labware due to the C-20 fatty diacid moiety. A typical volume is 1.0 mL per 5 mg vial.

In the head-to-head SURPASS-2 trial, Tirzepatide (15 mg) produced greater HbA1c reductions (−2.30% vs. −1.86%) and metabolic regulation research (−11.2 kg vs. −5.7 kg) than GLP-1 agonist peptide 1.0 mg at 40 weeks. In separate metabolic syndrome research trials, Tirzepatide 15 mg achieved 20.9% metabolic regulation research (comparative trial-1, 72 weeks) versus GLP-1 agonist peptide 2.4 mg achieving 14.9% (STEP 1, 68 weeks), though direct comparison is limited by differences in trial design and populations.

AminoCore Research offers Tirzepatide in three vial sizes: 5 mg, 10 mg, and 15 mg. All vials contain lyophilized powder at ≥99% purity (HPLC verified) with a Certificate of Analysis. Choose the appropriate size based on your research protocol and experimental requirements.

Tirzepatide (LY3298176) has a molecular weight of 4813.45 g/mol and CAS number 2023788-19-2. Its molecular formula is C225H348N48O68. The peptide consists of 39 amino acids based on the GIP backbone with two alpha-aminoisobutyric acid (Aib) substitutions at positions 2 and 13, and a C20 fatty diacid moiety conjugated via a gamma-glutamate-2x(2-(2-aminoethoxy)ethoxy)acetic acid linker at Lys20. This lipidation enables albumin binding and supports the extended half-life of approximately 5 days that permits once-weekly dosing in research protocols.

Tirzepatide is a dual agonist targeting the GIP and GLP-1 receptors, while Retatrutide (LY3437943) is a triple agonist that additionally activates the glucagon receptor. Tirzepatide shows biased signaling at GLP-1R (favoring cAMP over beta-arrestin recruitment) and full agonism at GIPR. Retatrutide's addition of glucagon receptor activity contributes to increased energy expenditure via hepatic and adipose effects, which may explain the greater weight reduction observed in Phase 2 retatrutide trials (-24.2%) compared with tirzepatide's SURMOUNT-1 results (-20.9%). Both are studied in metabolic and adiposity research models.

Yes. Repeated freeze-thaw cycles can accelerate aggregation and degradation of the peptide backbone, particularly at the Aib-modified positions and the fatty acid-linker junction. Researchers typically aliquot the reconstituted solution into single-use volumes immediately after reconstitution and store aliquots at -20°C or -80°C. Reconstituted solution should be kept at 2-8°C for short-term use (up to 4 weeks) and protected from light. Vigorous shaking should be avoided; gentle swirling ensures the C20 diacid moiety does not promote surfactant-like foaming that reduces peptide recovery.

Bacteriostatic water (0.9% benzyl alcohol) or sterile water for injection are the standard reconstitution solvents for research-grade Tirzepatide. The lyophilized powder should be reconstituted by directing the solvent stream against the vial wall rather than directly onto the powder, then allowed to dissolve without agitation for 2-3 minutes before gentle swirling. A typical concentration of 5 mg/mL (e.g., 10 mg peptide in 2 mL solvent) yields a clear, colorless solution. The presence of the fatty diacid tail confers slight amphiphilic character, so foaming should be avoided during handling.