FOXO4-DRI
Also written and searched as FOX04-DRI — same compound, same vial, same lot number.
FOXO4–p53 interfering D-retro-inverso peptide (FOX04-DRI, Proxofim), lyophilised. For in vitro research use only.
Key facts
- Compound:
- FOXO4-DRI
- Also known as:
- FOX04-DRI
- Purity:
- ≥99%, verified by HPLC
- Identity confirmed by:
- LC-MS, independent third-party lab
- CAS number:
- 2460055-10-9
- Molecular weight:
- 5358.2 g/mol
- Certificate of analysis:
- available on request, verifiable by lot number
- Ships from:
- Vancouver, BC — typically 2–5 business days, tracked and insured, no customs
- Intended use:
- in vitro laboratory research only — not for human or veterinary consumption
Page last updated
FOXO4-DRI — also written FOX04-DRI, and sold elsewhere as Proxofim — is a synthetic all-D retro-inverso peptide designed to interfere with the interaction between the transcription factor FOXO4 and p53.
FOXO4-DRI for cellular-senescence research, supplied to Canadian researchers by Popular Peptides. One 10 mg vial, ≥99% purity, CAS 2460055-10-9, molecular weight 5358.2 g/mol. Batch FOX4-401-002 was tested independently by Janoshik Analytical (task #93523): 99.724% HPLC purity and 12.37 mg measured content. The certificate is published on our lab-results page and can be checked against the lot number at popularpeptides.ca/verify. The compound was first described in a 2017 Cell study examining selective apoptosis of senescent cells in cell-culture and mouse models. Ships tracked and insured from Vancouver in 2 to 5 business days, with no customs step and no brokerage fee.
Supplied lyophilised for in vitro laboratory research use only; not intended for human or veterinary use.
Primary literature
- Targeted Apoptosis of Senescent Cells Restores Tissue Homeostasis in Response to Chemotoxicity and Aging — Cell, 2017
The founding study: interfering with FOXO4–p53 caused selective apoptosis of senescent cells in culture and was examined in chemotoxicity, fast-ageing and naturally aged mouse models.
- Senolytic Peptide FOXO4-DRI Selectively Removes Senescent Cells From in vitro Expanded Human Chondrocytes — Frontiers in Bioengineering and Biotechnology, 2021
In vitro human-cell work: at 25 µM it cleared much of a late-passage chondrocyte population while sparing early-passage cells.
Cited for research context. A citation is not a claim that this compound is safe, effective, or approved for any use.
⚠️ Research Use Only. This compound is intended for in vitro research and laboratory use only. Not for human or veterinary consumption.
FOXO4-DRI — compound background
46-residue all-D retro-inverso peptide
FOXO4-DRI was designed in the laboratory of Peter de Keizer (Erasmus University Medical Center) and published in Cell in 2017 (Baar et al.). It mimics the region of the transcription factor FOXO4 that binds p53, but is built from D-amino acids in reversed order — a retro-inverso design that keeps the side-chain layout while making the backbone unrecognisable to proteases. A cationic, arginine-rich tail derived from the HIV-TAT cell-penetrating sequence carries it into cells.
Solubility & reconstitution
Strongly basic — the sequence carries many arginine and lysine residues — so it dissolves readily in plain aqueous diluent without acidification. The same positive charge makes it stick to negatively charged surfaces such as untreated glass.
Commonly worked at 1-5 mg/mL.
Storage
Sealed powder is stable at -20 °C long-term; keep desiccated. Refrigerate at 2-8 °C, protected from light, and aliquot for anything beyond short-term use.
Commonly worked with for 2-3 weeks at 2-8 °C in bacteriostatic water.
Stability
Because every residue is a D-amino acid, ordinary proteases barely cleave it — chemical routes (deamidation, oxidation) and surface loss matter far more than enzymatic breakdown.
Reading the Certificate of Analysis
Check the HPLC purity and the measured content per vial. For a 46-residue, highly cationic peptide the gross powder weight includes counter-ion (typically trifluoroacetate) and water, so measured peptide content is the more informative number. Where mass data is given, the target is about 5358 Da.
Background and handling information is educational, for in-vitro laboratory research use only — not medical advice, dosing, or usage guidance, and not a description of use in humans or animals.
How much does FOXO4-DRI cost in Canada?+
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FOXO4-DRI laboratory reference
FOXO4-DRI is 46-residue all-d retro-inverso peptide. Handling requirements follow from that chemistry rather than from generic peptide guidance — the pages below cover each aspect specifically for this compound.
Lyophilized and reconstituted storage conditions, plus the practical working window.
Diluent selection, dissolution behaviour, and the calculator preset for this compound.
Which solvents work, why, and what abnormal dissolution behaviour indicates.
The specific chemical routes by which this molecule breaks down, and how to limit each.
Which assays are informative for this molecule, and what to actually check on its COA.
Compound-specific bench practices, and the errors most often made with this molecule.
What to inspect on arrival, and which conditions actually warrant rejecting a vial.
Questions specific to this compound — structure, chemistry, and common misconceptions.
FOXO4-DRI compared with
Reference content is educational laboratory-handling information for in-vitro research use only — not medical advice, not usage guidance, and not a protocol.