Peptide Physicochemical Properties
Peptide Physicochemical Properties
Section titled “Peptide Physicochemical Properties”Comprehensive physicochemical data for major therapeutic and research peptides. Values represent native/unmodified forms unless otherwise noted.
Properties Table
Section titled “Properties Table”| Peptide | MW (Da) | pI | Net Charge (pH 7.4) | t½ (plasma) | Hydrophobicity Index | Solubility Class |
|---|---|---|---|---|---|---|
| Insulin (human) | 5,808 | 5.4 | −2 | 4–5 min (iv) | −0.12 | Freely soluble |
| Oxytocin | 1,007 | 7.7 | +1 | 3–5 min | 0.04 | Freely soluble |
| Vasopressin (AVP) | 1,084 | 10.9 | +2 | 10–20 min | −0.28 | Freely soluble |
| Semaglutide | 4,114 | 6.2 | −2 | ~165 h (SC) | 0.15 | Soluble |
| Tirzepatide | 4,814 | 5.8 | −3 | ~120 h (SC) | 0.18 | Soluble |
| GLP-1 (7-36) amide | 3,298 | 6.0 | −1 | 2–3 min | −0.05 | Freely soluble |
| Exenatide | 4,187 | 5.3 | −2 | 2.4 h (SC) | 0.08 | Soluble |
| Liraglutide | 3,751 | 5.6 | −2 | 13 h (SC) | 0.11 | Soluble |
| BPC-157 | 1,419 | 8.2 | +3 | 15–20 min (unmod) | −0.35 | Freely soluble |
| TB-500 (Thymosin β4) | 4,921 | 5.2 | −4 | 2–4 h (SC) | −0.22 | Freely soluble |
| GHK-Cu | 340 (peptide) | 8.5 | +2 (peptide) | 1–2 h (SC) | −0.18 | Freely soluble |
| Melanotan II | 1,024 | 8.1 | +2 | 1–2 h | 0.06 | Freely soluble |
| PT-141 (Bremelanotide) | 1,025 | 8.1 | +2 | 2.7 h (SC) | 0.07 | Freely soluble |
| CJC-1295 (no DAC) | 3,368 | 5.7 | −3 | 6–8 min | −0.09 | Freely soluble |
| Ipamorelin | 712 | 6.4 | +1 | 2 h | 0.22 | Freely soluble |
| GHRP-6 | 874 | 8.0 | +3 | 15–20 min | −0.12 | Freely soluble |
| Thymosin β4 | 4,921 | 5.2 | −4 | 2–4 h | −0.22 | Freely soluble |
| Thymosin α1 | 3,108 | 4.3 | −6 | 2 h | −0.31 | Freely soluble |
| VIP (vasoactive intestinal peptide) | 3,326 | 4.6 | −5 | 1–2 min | −0.15 | Freely soluble |
| PACAP-38 | 4,533 | 5.0 | −6 | 2–3 min | −0.10 | Freely soluble |
| DSIP | 903 | 7.0 | 0 | 8–15 min (iv) | 0.05 | Soluble |
| Orexin A | 2,937 | 4.8 | −3 | 5–10 min | −0.08 | Soluble |
| Bradykinin | 1,060 | 12.0 | +3 | 15–30 sec | −0.20 | Freely soluble |
| Substance P | 1,348 | 7.5 | +1 | 2–3 min | −0.03 | Freely soluble |
| CGRP (α) | 3,790 | 4.9 | −5 | 6–10 min | −0.11 | Soluble |
| Amylin (IAPP) | 3,903 | 8.5 | +2 | 15–20 min | 0.14 | Soluble |
| Calcitonin (human) | 3,432 | 6.8 | +1 | 10–15 min | −0.05 | Soluble |
| PTH (1-84) | 9,425 | 7.1 | +1 | 2–4 min | −0.09 | Soluble |
| hCG | 36,700 | 4.6 | −10 | 24–36 h (SC) | 0.02 | Soluble |
| FSH | 32,600 | 4.2 | −12 | 36–48 h (SC) | 0.01 | Soluble |
| LH | 28,500 | 4.4 | −11 | 20–24 h (SC) | 0.00 | Soluble |
| TSH | 28,000 | 4.3 | −10 | 60 min (iv) | −0.01 | Soluble |
| ACTH | 4,541 | 6.5 | +1 | 10–15 min | 0.02 | Soluble |
| α-MSH | 1,646 | 9.5 | +3 | 1–3 min | 0.08 | Freely soluble |
| Insulin glargine | 6,064 | 6.7 | 0 | 24–36 h (SC) | 0.00 | Soluble (acid) |
| Insulin detemir | 5,917 | 6.2 | −1 | 12–18 h (SC) | 0.10 | Soluble |
| Insulin degludec | 9,541 | 6.0 | −2 | >42 h (SC) | 0.05 | Soluble |
| Dulaglutide | 63,700 | 5.5 | −8 | ~90 h (SC) | 0.08 | Soluble |
| Exenatide ER | 4,187 | 5.3 | −2 | ~7 days (SC) | 0.08 | Insoluble (microsphere) |
| Semaglutide oral | 4,114 | 6.2 | −2 | ~165 h (SC) | 0.15 | Soluble |
| Orforglipron | 810 | 5.0 | −3 | ~24 h (PO) | 0.35 | Soluble |
| Retatrutide | 5,850 | 5.6 | −4 | ~48 h (SC) | 0.12 | Soluble |
| Amycretin | 4,400 | 5.8 | −3 | ~36 h (SC) | 0.14 | Soluble |
| Danuglipron | 728 | 4.8 | −4 | ~14 h (PO) | 0.42 | Soluble |
| Tesamelin | 1,500 | 7.8 | +2 | 4–6 h (SC) | 0.10 | Soluble |
| Bremelanotide | 1,025 | 8.1 | +2 | 2.7 h (SC) | 0.07 | Freely soluble |
| Alprostadil (PGE₁) | 354 (non-peptide) | — | — | 5–10 min (iv) | — | Soluble |
| Oxytocin (nasal) | 1,007 | 7.7 | +1 | 10–20 min (nasal) | 0.04 | Freely soluble |
| Desmopressin | 1,183 | 8.8 | +2 | 6–8 h (SC) | −0.15 | Freely soluble |
| Octreotide | 1,019 | 8.4 | +2 | 1.5–2 h (SC) | 0.18 | Freely soluble |
| Lanreotide | 1,500 | 7.5 | +1 | 23–30 days (SC) | 0.22 | Soluble |
| Pasireotide | 1,636 | 8.0 | +2 | 8–12 h (SC) | 0.20 | Soluble |
| Carfilzomib | 719 (non-peptide) | — | — | 1–2 h | — | Insoluble |
| Bortezomib | 384 (non-peptide) | — | — | 9–15 h | — | Soluble |
| Carmustine | 214 (non-peptide) | — | — | 1.3 h | — | Slightly soluble |
| Leuprolide | 1,209 | 7.2 | +1 | 3–4 h (SC) | 0.12 | Soluble |
| Goserelin | 1,262 | 7.0 | +1 | 2–4 h (SC) | 0.10 | Soluble |
| Triptorelin | 1,312 | 7.5 | +2 | 2–5 h (SC) | 0.08 | Soluble |
| Buserelin | 1,239 | 7.3 | +2 | 80 min (iv) | 0.14 | Soluble |
| Nafarelin | 1,322 | 7.1 | +1 | 2–3 h (SC) | 0.16 | Soluble |
| Histrelin | 1,325 | 7.4 | +2 | 1–2 h (SC) | 0.15 | Soluble |
- MW: Molecular weight in Daltons for the peptide component; glycoconjugates (dulaglutide, semaglutide) include linker.
- pI: Isoelectric point; pI < 7 = acidic, pI > 7 = basic, pI ≈ 7 = neutral.
- Net charge at pH 7.4: Calculated from titration curves and pKa values of ionizable groups.
- Hydrophobicity index: Based on HPLC retention times or calculated logP; higher = more hydrophobic.
- Solubility class: Defined by USP/Ph. Eur. criteria at 25°C, pH 7.4 PBS.
- Half-life values are approximate and vary with formulation, route, and species.
Solubility Classifications
Section titled “Solubility Classifications”| Class | Definition | Examples |
|---|---|---|
| Freely soluble | >1 g/10 mL | BPC-157, oxytocin, desmopressin |
| Soluble | 1–10 g/10 mL | Semaglutide, liraglutide, octreotide |
| Slightly soluble | 0.1–1 g/10 mL | Carmustine |
| Insoluble | <0.1 g/10 mL | Exenatide ER microspheres |