High Purity FOXO4 Polypeptide Compound Water Soluble Freeze Dried Powder for Formula Development & Scientific Research

FOXO4-DRI is a synthetic peptide with an all-D-amino-acid retro-inverso sequence, first reported in 2017 by the research team led by Peter de Keizer at Erasmus University Medical Center in Rotterdam, Netherlands, and a typical representative of cell-permeable peptide antagonists. Adopting a D-retro-inverso molecular design strategy—replacing natural L-amino acids with D-amino acids and reversing the sequence—this peptide exhibits significantly enhanced resistance to proteolytic degradation, improved in vitro/in vivo stability, and prolonged half-life. As a dedicated laboratory research tool compound, FOXO4-DRI is primarily utilized in cell biology, molecular biology, aging mechanism research, signaling pathway regulation, exploration of cell apoptosis mechanisms, and related basic medical experiments, serving as a core reagent in the field of aging and cellular homeostasis research.

Structure & Key Features

• Unique D-Retro-Inverso Design: All-sequence D-amino acid substitution plus sequence reversal, optimized spatial conformation, strong anti-enzymatic degradation capability, and stability far superior to conventional L-type peptides.
• High Cell Permeability: Excellent cell membrane penetration ability, efficiently entering the cytoplasm and nucleus to act on intracellular targets without the need for transfection reagents.
• High Target Specificity: Precisely targets the FOXO4-p53 signaling pathway, specifically interfering with the interaction between FOXO4 and p53 proteins without affecting normal physiological functions of healthy cells.
• High Purity & Low Endotoxin: Manufactured via advanced solid-phase synthesis and efficient purification processes, with HPLC purity ≥98% and endotoxin content minimized, suitable for sensitive cell-based assays.
• Excellent Batch Consistency: Rigorous quality control system; each batch is accompanied by a complete COA, HPLC chromatogram, MSDS and amino acid analysis report, ensuring experimental reproducibility and reliability.
  

  Research Applications

  
  
  • Studies on cellular senescence mechanisms and senescence-associated signaling pathways.
  • Exploration of FOXO4 transcription factor functions and regulatory mechanisms.
  • Experiments on p53 protein-mediated cell apoptosis and cycle regulation.
  • Basic research on senolytic-mediated clearance of senescent cells.
  • Investigations into tissue homeostasis maintenance and regenerative repair mechanisms.
  • Research on the correlation between oxidative stress, DNA damage and cell fate decisions.
  • Screening, activity evaluation and mechanism validation of anti-aging drug candidates.
  
  

• 1. General Safety & Pre-operation Requirements

  
  
  All operations related to FOXO4-DRI lyophilized powder must be carried out in a standard sterile, low-dust laboratory environment. It is recommended to use a professional laminar flow cabinet to isolate external pollutants and ensure the purity of experimental materials. Operators must wear complete personal protective equipment including lab coat, disposable nitrile gloves, safety goggles and dust-proof mask throughout the whole process.
  
  
  Before opening the sealed product vial, place the unopened vial at room temperature (15–25°C) for sufficient temperature equilibration. This step can effectively prevent the condensation of water vapor inside the bottle caused by large temperature difference, so as to avoid the peptide powder absorbing moisture, caking and deteriorating in advance. Do not open the vial in a humid environment for a long time, as this product has strong hygroscopicity and is easy to be oxidized when exposed to air for a long time. All tools, pipettes, and containers used for sampling and dissolution must be sterilized in advance to prevent cross-contamination and microbial pollution.
  
  

  2. Recommended Solvents for Reconstitution

  
  
  According to different experimental systems and research purposes, multiple laboratory-grade solvents can be selected for dissolution:
  
  
  • Sterile Deionized Water: Suitable for general biochemical preparation and aqueous phase experimental systems.
  • Bacteriostatic Water: Containing mild preservatives, applicable to experiments requiring multiple sampling and short-term storage of stock solution.
  • Phosphate Buffered Saline (PBS, pH 7.2–7.4): The most commonly used solvent for cell culture, in vitro cell experiments and biological pathway research.
  
  
  It is not recommended to use organic solvents with strong polarity to dissolve this peptide, so as to prevent changes in peptide molecular conformation and affect the progress of follow-up experiments.
  
  

  3. Detailed Reconstitution Steps Clean and disinfect the experimental tabletop with 70% isopropyl alcohol, and wait until the alcohol volatilizes completely to keep the operating area clean and sterile. Take sterile alcohol swabs to fully wipe and disinfect the rubber stopper of the peptide vial and the solvent vial respectively, and let it stand for 10 to 15 seconds for natural air drying. Use a sterile pipette to accurately draw the required volume of pre-selected solvent. Aim the pipette tip at the inner wall of the peptide vial, and add the solvent slowly and continuously along the wall. Do not add the solvent directly onto the loose lyophilized powder, otherwise it will cause a large number of foams and lead to peptide molecular denaturation. After adding the solvent, place the vial upright and let it stand quietly for 1 to 2 minutes to fully moisten the powder. Hold the vial and swirl it gently and continuously at a constant speed for 30 to 60 seconds. Do not shake violently, shake upside down or perform high-speed vortex oscillation, so as to protect the complete spatial structure of the D-retro-inverso peptide. After dissolution, carefully observe the state of the solution. The qualified solution is clear and transparent, without visible suspended particles, floccules, turbidity and precipitation. If abnormal phenomena occur, please stop using it immediately. Immediately mark the vial surface with product name, batch number, prepared concentration, reconstitution date and operator information for traceability management.
  4. Aseptic Subpackaging & Solution Management After the completion of reconstitution, if the total volume of stock solution is large and it needs to be used in batches for a long time, please carry out aseptic subpackaging operation in the laminar flow cabinet. Divide the prepared mother solution into multiple small-capacity sterile centrifuge tubes or small sealed vials according to the conventional dosage of daily experiments. Independent subpackaging can effectively reduce the frequency of repeated opening of the original vial and avoid repeated freeze-thaw of the remaining solution, which is the key to maintain the long-term stability of the peptide solution. Each subpackaged container shall be marked with corresponding concentration, preparation time and validity period. When taking liquid each time, use a new sterile pipette tip to prevent cross-contamination between different experimental groups.

  
  

  5. Scientific Storage Rules (Powder & Reconstituted Solution)

  
  

  Lyophilized Powder (Unopened Original Vial)

  
  
  • Long-term storage: Seal tightly and store in a low-temperature environment of -20°C, away from heat sources, strong light and volatile chemical reagents. Under this condition, the product can maintain stable chemical properties and molecular structure for a long time.
  • Short-term temporary storage (within 4 weeks): It can be placed in a refrigerated environment of 2–8°C for sealed storage, and still needs to be protected from light and moisture.
  • After partial sampling: Reseal the vial immediately after each use, squeeze out the excess air inside the bottle as much as possible, and put it back into the low-temperature storage environment in time.
  
  

  Reconstituted Aqueous Solution

  
  
  • Short-term storage (within 14 days): Seal and store at 2–8°C in a refrigerated and dark environment. If using bacteriostatic water, the stable storage time can be appropriately extended.
  • Medium and long-term storage: After aseptic subpackaging, place it in a -20°C refrigerator for freezing. Repeated freeze-thaw cycles are strictly prohibited, which will seriously damage the peptide structure and reduce experimental effectiveness.
  • Reminder: The stability of the diluted working solution is poor. It is recommended to prepare the working solution on the same day and use it up on the same day.
  
  

  6. Stability Notes & Inspection Before Use

  
  
  FOXO4-DRI belongs to D-retro-inverso modified peptide. Although its overall stability is superior to ordinary L-type peptides, it is still sensitive to high temperature, excessive humidity, strong ultraviolet rays and long-term air exposure. During daily preservation and use, always keep the storage environment dry and ventilated.
  
  
  Before each use, carefully check the appearance state of powder or solution. If the powder is agglomerated, discolored and damp, or the solution becomes turbid, precipitated and discolored, it indicates that the product has deteriorated, and it must be discarded and shall not be used in any experimental work.
  
  

  7. Waste Disposal Specifications

  
  
  All residual peptide powder, waste solution, used vials, pipette tips and other experimental wastes shall be classified and disposed of in accordance with local laboratory hazardous waste management regulations. Do not pour the waste liquid directly into the drainage pipeline, and do not discard the polluted containers at will. All disposal operations shall be completed by professional laboratory personnel to ensure laboratory environmental safety.

• 1. 1. General Storage Principle & Environmental Requirements

     
     
     FOXO4-DRI is a type of D-retro-inverso synthetic peptide compound. Although its molecular structure is optimized to gain stronger anti-degradation ability compared with conventional linear peptides, the product is still sensitive to high temperature, ambient humidity, strong ultraviolet radiation, long-term air exposure and oxidative environment. Therefore, standardized storage management must be implemented throughout the whole cycle from warehousing, standby use to post-opening preservation, so as to fully maintain the complete molecular conformation, chemical stability and inherent properties of the peptide material.
     
     
     The storage area shall be kept dry, clean, well ventilated and away from all kinds of corrosive volatile chemical reagents, strong light sources, heat sources and direct sunlight. It is forbidden to place this product together with toxic, harmful, strong oxidizing or strong reducing experimental supplies, to avoid cross-impact and accidental contamination. All storage containers must be kept tightly sealed to isolate external moisture and air.
     
     

     2. Storage Method for Unopened Lyophilized Powder (Original Sealed Vial)

     
     

     Long-term Storage (Full shelf life retention)

     
     
     For long-term preservation lasting several months or even longer, please place the intact unopened vials in a professional laboratory low-temperature refrigerator at -20°C. Ensure the vials are fully sealed, arranged neatly inside the cabinet, and kept away from the cold air outlet to prevent excessive temperature fluctuation. Under the environment of constant low temperature, sealed, dry and dark, the product can steadily maintain all technical indicators within the full validity period of 24 months, without obvious decline of purity and structural activity. This is the most recommended storage mode for bulk inventory and long-term standby materials.
     
     

     Short-term Storage (Within 4 weeks)

     
     
     If the product will be used continuously within a short period of time, it can be temporarily stored in a constant temperature refrigeration cabinet at 2°C ~ 8°C. Keep the original package sealed tightly, avoid frequent moving and collision, and strictly prevent moisture from penetrating into the vial. This storage condition is suitable for laboratory conventional standby materials with frequent use, and can effectively guarantee stable quality in the short term.
     
     

     Room Temperature Temporary Placement (Before opening & transit)

     
     
     When transferring the product, sorting goods or equilibrating temperature before operation, the sealed vials can be placed in a cool indoor environment at 15°C ~ 25°C for short-term placement. The retention time at room temperature shall not be too long, and direct sunlight and high temperature environment must be avoided. This mode is only applicable to temporary placement before formal storage and experimental operation, and shall not be used for long-term preservation.
     
     

     3. Storage Management after Opening & Partial Sampling

     
     
     After the original sealed vial is opened for sampling and material taking, the tightness of the package will be reduced, and the internal powder will be in contact with external air and moisture for a certain time, which will increase the risk of moisture absorption and oxidation. After each sampling is completed, please immediately tighten the rubber stopper and seal the bottle mouth completely. It is suggested to gently squeeze out the excess air inside the vial before sealing, so as to reduce the contact between residual powder and oxygen.
     
     
     Put the semi-used product back into the specified low-temperature storage area in a timely manner according to the above long-term or short-term storage standards. Mark the opening date on the surface of the vial for record tracking. It is recommended to use up the remaining powder within 1 month after opening, to prevent gradual deterioration caused by long-term repeated contact with air. Do not leave the opened vial in an open state for a long time in the laboratory operating area.
     
     

     4. Storage Rules for Reconstituted Aqueous Solution

     
     
     After the lyophilized powder is dissolved into aqueous solution by solvent, the stability will decrease significantly compared with solid powder, and the requirements for storage conditions are more stringent.
     
     

     Short-term Storage of Stock Solution

     
     
     The prepared stock solution can be sealed and stored in a refrigerated environment of 2°C ~ 8°C, protected from light. Under this condition, the solution can maintain stable state within 7 to 14 days. If bacteriostatic water is adopted for reconstitution, the stable storage period can be appropriately extended. It is necessary to use light-proof sealed containers to avoid light-induced molecular degradation.
     
     

     Medium & Long-term Frozen Storage

     
     
     For the solution that needs to be stored for more than two weeks, please carry out aseptic subpackaging first, divide the mother solution into multiple small-capacity sealed containers, and then place them in a -20°C low-temperature refrigerator for frozen preservation. Independent subpackaging is an essential measure to extend the storage cycle.
     
     

     Key Prohibition Reminder

     
     
     Repeated freeze-thaw cycles are strictly prohibited. Each time of freezing and thawing will destroy the peptide molecular structure, lead to activity attenuation and purity decline, and directly affect the accuracy and repeatability of subsequent experimental data. The diluted working solution has the weakest stability, so it is required to be prepared and used on the same day, and no overnight storage is advocated.
     
     

     5. Precautions during Transportation & Handover

     
     
     During long-distance transportation and internal laboratory handover, this product shall be transported with professional cold storage equipment or ice packs to maintain low-temperature environment. Avoid severe vibration, flipping and extrusion of the packaging during transportation, to prevent the vial from breaking and powder leakage. After receiving the goods, inspect the package integrity first, and then transfer it to the specified storage area for classified management in time.
     
     

     6. Regular Inspection & Quality Judgment during Storage

     
     
     Carry out regular visual inspection for products in storage periodically. Observe the state of the lyophilized powder: qualified powder is loose white or off-white solid without caking, discoloration and deliquescence. Check the reconstituted solution: qualified solution is clear and transparent without turbidity, floccules, precipitation and color change. Once abnormal deterioration is found, stop using immediately and dispose of it in accordance with laboratory hazardous waste regulations.

Core Business & Product Portfolio

• Therapeutic peptides: SS-31 (Elamipretide), Tirzepatide, Semaglutide, Retatrutide (RT20), etc.
• Functional peptides: GHK-Cu, TB500, KPV, NAD, Glutathione, etc.
• Custom peptide services: Custom synthesis of complex sequences, long-chain peptides (up to 200 amino acids) and cyclic peptides, as well as various modification services (N-methylation, unusual amino acid incorporation, etc.).

R&D & Manufacturing Strength

• Technical expertise: Mastery of core technologies including solid-phase peptide synthesis (SPPS), liquid-phase synthesis, advanced purification (HPLC) and strict structural characterization.
• Quality assurance: All products are produced in compliance with cGMP standards, with complete CoA, HPLC and MS reports to ensure batch-to-batch consistency and high purity (≥98%).
• Production capacity: Equipped with professional production bases in Guangzhou, supporting small-batch R&D samples to large-scale commercial production, with stable supply capacity.

Global Market & Service Philosophy

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