Tirzepatide (LY3298176) is a dual GIP and GLP-1 receptor agonist under development for the treatment of type 2 diabetes mellitus (T2DM), obesity, and nonalcoholic steatohepatitis. Early phase trials in T2DM indicate that tirzepatide improves clinical outcomes beyond those achieved by a selective GLP-1 receptor agonist. Tirzepatide was discovered by engineering GLP-1 activity into the GIP sequence. It is an imbalanced dual agonist in favor of GIPR over GLP-1R activity as the molecule shows equal affinity for the GIPR compared with native GIP but binds the GLP-1R with approximately 5-fold weaker affinity than native GLP-1. The imbalanced nature of tirzepatide may be critical to maximizing the efficacy of a dual agonist because dose escalation for GLP-1R activation can be limited by gastrointestinal effects such as nausea and vomiting, while GIPR engagement is not known to be associated with similar events. As a consequence, a pharmacological profile favoring potency at the GIPR offers an opportunity to fully engage this pathway while minimizing GLP-1–related tolerability issues. In addition to a potency ratio toward GIPR activity, tirzepatide contains a C20 unsaturated di-acid acyl chain to affect albumin binding, and the overall properties of the molecule enable once-weekly dosing. Beyond convenience, this pharmacokinetic feature may confer pharmacodynamic benefit, as high and sustained concentrations of selective GLP-1R agonists have enhanced clinical efficacy.

Notes:

• *Tirzepatide (LY3298176) is lyophilized in a package of 5mg/tube.
• Store lyophilized Tirzepatide (LY3298176) in a refrigerator at -20°C to 4°C (-4°F to 39°F)
• If needed, liquid Tirzepatide (LY3298176) can be stored unrefrigerated at temperatures not to exceed 30ºC (86ºF) for up to 3 weeks.
• Do not freeze liquid Tirzepatide (LY3298176).
• Store Tirzepatide (LY3298176) in the original tube and protect it from light.
• This product is not sterile, please sterilize it by filtration before cell assays or animal experiments.

• Willard FS, Douros JD, Gabe MB, Showalter AD, Wainscott DB, Suter TM, et al. Tirzepatide is an imbalanced and biased dual GIP and GLP-1 receptor agonist. JCI Insight. 2020;5(17)
• Min T, Bain SC. The Role of Tirzepatide, Dual GIP and GLP-1 Receptor Agonist, in the Management of Type 2 Diabetes: The SURPASS Clinical Trials. Diabetes Ther. 2021;12(1):143-157
• Willard FS, Douros JD, Gabe MB, Showalter AD, Wainscott DB, Suter TM, et al. Tirzepatide is an imbalanced and biased dual GIP and GLP-1 receptor agonist. JCI Insight. 2020;5(17)

三氟乙酸（TFA）是一种强酸，常用于从固相树脂中裂解合成的多肽，也可用于提高多肽纯化步骤中的HPLC性能。默认情况下，定制的多肽是以冻干的TFA盐的形式交付的，其中TFA的含量可能高达10-45%。

定制多肽中的TFA可能会导致后续检测数据出现无法解释的差异。例如，nM浓度的TFA已被证明会干扰细胞实验，在某些情况下会抑制细胞增殖，而在其他情况下会增加细胞活力。

TFA去除服务推荐用于:

• 将用于细胞试验的多肽
• 将被用作原料药或制成品的多肽
• 含有大量碱性残基的亲水多肽

干品多肽的重量中不仅仅包含多肽，还包含有一些非肽的组份，如水、被吸收的溶剂、配位离子和盐等。肽的净含量是指肽在其中的重量百分比，这个百分比的数值范围很大，可能从50%到90%，取决于纯度、序列以及合成和纯化的方法，不要将肽的净含量和肽的纯度混为一谈，他们是两个完全不同的概念。纯度通常是通过HPLC测定的。纯度定义的是多肽样品中含正确序列的组分的百分比，而肽的净含量是指样品中肽类物质相对于总物质所占的百分比，肽的净含量通常是氨基酸组分分析或紫外分光法测定的，这个信息主要是在一些对肽的浓度很敏感的实验中，对计算肽的浓度是很重要的。