Materials and Equipment Required

Before beginning, gather the following materials to ensure a smooth workflow:

• Recombinant Human HPR Protein (SKU: rp369234, Aladdin Scientific)
• Sterile deionized water or phosphate-buffered saline (PBS, pH 7.4)
• Microcentrifuge tubes (low-protein-binding, 1.5 mL)
• Calibrated micropipettes and sterile tips
• Microcentrifuge capable of ≥10,000 × g
• Dry ice or liquid nitrogen for snap-freezing aliquots
• -20°C and/or -80°C freezer for long-term storage
• Protein quantification reagents (e.g., BCA or Bradford assay kit)
• Appropriate assay buffers compatible with downstream applications

Ensure all equipment is cleaned and calibrated, and that the work area is maintained under aseptic conditions to prevent protein degradation or contamination.

Reconstitution Procedure

Follow these steps carefully to reconstitute Recombinant Human HPR Protein without compromising its activity:

1. Equilibrate the vial: Allow the lyophilized protein vial to equilibrate to room temperature for 10–15 minutes before opening to minimize condensation-induced dilution.
2. Prepare reconstitution buffer: Use sterile deionized water or PBS (pH 7.4) as the primary reconstitution solvent. Refer to the product datasheet for the manufacturer's specific recommendation.
3. Add solvent gently: Pipette the appropriate volume of reconstitution buffer slowly along the inner wall of the vial. Do not vortex directly.
4. Mix by gentle rotation: Gently swirl or rotate the vial for 3–5 minutes until the protein is fully dissolved. Avoid vigorous agitation, which can cause protein denaturation or aggregation.
5. Centrifuge briefly: Spin the reconstituted solution at low speed (1,000–2,000 × g, 1 minute) to collect any residual material from the vial walls.
6. Verify dissolution: The solution should appear clear; any visible particulates may indicate incomplete dissolution or aggregation — in such cases, gently re-mix and inspect again.
7. Determine protein concentration: Quantify using a BCA or Bradford assay against a BSA standard curve to confirm accurate working concentrations.

Note: Always consult the specific product datasheet (absea#PP-25305) for lot-specific reconstitution volumes and concentrations.

Storage and Aliquoting Guidelines

Proper storage is critical for maintaining the long-term stability and biological activity of Recombinant Human HPR Protein:

• Short-term storage (up to 1 week): Store reconstituted protein at 4°C. Inclusion of a carrier protein (e.g., 0.1% BSA) is recommended to stabilize dilute preparations.
• Long-term storage: Aliquot the reconstituted protein into single-use volumes using low-binding microcentrifuge tubes. Store aliquots at -20°C for routine use or at -80°C for extended storage periods.
• Avoid freeze-thaw cycles: Repeated freeze-thaw cycles significantly reduce protein activity and increase aggregation. Prepare aliquots sized for single experimental use.
• Lyophilized (unopened) protein: Store at -20°C or as indicated on the product label. Protect from moisture.
• Labeling: Clearly label all aliquots with protein identity, concentration, date of reconstitution, and aliquot number for full traceability.

Adhere to the storage conditions specified on the product datasheet (absea#PP-25305) to ensure compliance with the manufacturer's validated stability data.

Assay Application Guidelines

Recombinant Human HPR Protein is suitable for use in a range of in vitro research applications. Researchers should validate optimal working conditions for each specific assay:

• ELISA: Use as a standard or positive control. Prepare serial dilutions in assay diluent buffer. Verify linear range prior to quantitative use.
• Western Blot (WB): Load an appropriate quantity of protein (typically 50–500 ng per lane, to be optimized empirically) alongside molecular weight markers. Use a validated anti-HPR antibody for detection.
• Functional/Biological Assays: Determine the appropriate concentration range based on published literature for HPR-related biological activity. Titration experiments are strongly recommended before full-scale assays.
• Cell-based assays: Confirm the absence of endotoxin contamination before adding recombinant protein to cell cultures. Endotoxin levels should meet requirements appropriate for cell-based work.

Important: All working concentrations and assay conditions should be empirically optimized in your specific experimental system. Results may vary depending on cell type, assay format, and detection reagents used.

Troubleshooting Common Issues

If unexpected results are obtained when working with Recombinant Human HPR Protein, consider the following troubleshooting guidance:

If problems persist after applying these corrective actions, contact Aladdin Scientific technical support with your lot number and experimental details for further assistance.