Phosphate Buffered Saline is a reconstitution research compound currently in stock directly from a verified Chinese manufacturer. Every batch is HPLC-verified and shipped with a Certificate of Analysis (COA). Sourcing is direct — no intermediaries. Minimum order value is $600 USD. International shipping available.
Phosphate-Buffered Saline (PBS) is a standard isotonic buffer solution used throughout biological research as a physiological-composition diluent, wash solution, and vehicle for peptide reconstitution. The standard 1× PBS formulation (pH 7.4) contains 137 mM NaCl, 2.7 mM KCl, 10 mM Na₂HPO₄, and 1.8 mM KH₂PO₄ — matching mammalian extracellular fluid osmolality (~290 mOsm) and physiological pH. Its ionic composition is designed not to interfere with cell viability, receptor binding, or enzymatic activity, making it the near-universal choice for biological sample preparation and experimental vehicle controls.
In peptide research, PBS serves multiple critical roles: as the reconstitution vehicle for lyophilized peptides where aqueous solubility at neutral pH is sufficient; as the vehicle for in vivo injections (subcutaneous, intraperitoneal, intravenous); as the wash buffer in ELISA and Western blot protocols; and as the diluent in cell culture experiments. The buffering capacity of the phosphate system (pKa ~7.2) maintains pH stability against CO₂ equilibration — though for cell culture applications, bicarbonate-buffered systems (HEPES, DMEM) are often combined with PBS for atmospheric CO₂ compatibility.
PeptidesFromChina.co supplies PBS as a sterile, endotoxin-tested solution in sealed vials at pH 7.4 ± 0.1, suitable for use as research vehicle and reconstitution medium. Certificate of Analysis accompanies every batch. All products are for laboratory research use only.
| Chemical Class | Isotonic phosphate buffer solution |
|---|---|
| Composition (1×) | 137 mM NaCl, 2.7 mM KCl, 10 mM Na₂HPO₄, 1.8 mM KH₂PO₄ |
| pH | 7.4 ± 0.1 |
| Osmolality | ~280-290 mOsm/kg (isotonic) |
| Endotoxin | ≤0.1 EU/mL (LAL tested) |
| Research Applications | Peptide reconstitution, injection vehicle, ELISA wash buffer, cell culture supplement, histology |
| Form | Sterile aqueous solution |
| Storage | Room temperature or 2-8°C; avoid freezing; use sterile technique to prevent contamination |
| CAS Number | N/A — formulated solution (multi-component) |
| Molecular Weight | N/A — formulated solution |
| Molecular Formula | N/A — formulated solution |
| Sequence | N/A — not a peptide |
| Name | Strength | Pack Size | Purity | Availability | Price (USD) |
|---|---|---|---|---|---|
| Phosphate Buffered Saline | 3 ml | 10 vials | Pharmaceutical grade | In Stock | $9.00 |
| Phosphate Buffered Saline | 10 ml | 10 vials | Pharmaceutical grade | In Stock | $12.00 |
Testing method: Sterile / endotoxin tested. Every batch is tested before shipment. Purity ≥99% confirmed per batch.
Certificate of Analysis (COA) is included with every order. Documentation covers purity, molecular weight, and batch identification.
PBS at pH 7.4 is suitable for reconstituting peptides with good aqueous solubility at physiological pH. Peptides with basic sequences (high pI > 8) dissolve readily in PBS; acidic peptides may require adjustment. For peptides requiring acidic reconstitution (e.g., GHRH analogues — often reconstituted in acetic acid 0.1%), PBS can be added as a secondary diluent. The choice of reconstitution vehicle affects peptide aggregation, solubility, and stability — PBS provides a physiologically neutral starting point.
In animal studies, PBS-vehicle injection controls are essential for separating compound-specific effects from the mechanical stress of injection (needle trauma, injection volume, solution osmolality). PBS's isotonic, physiological-pH composition minimizes tissue irritation at injection sites, making it the standard negative control vehicle in subcutaneous, intraperitoneal, and intravenous peptide research protocols.
PBS with Tween-20 (PBST) is the standard wash buffer in ELISA protocols, reducing non-specific antibody binding while preserving specific antigen-antibody interactions. PBS alone is used as the diluent for standard curve preparation in sandwich ELISAs and as the blocking buffer base. Proper PBS composition (correct salt concentration and pH) is critical for reproducible immunoassay results — small deviations affect antibody binding kinetics.
Use PBS when: the peptide will be used immediately, the research protocol requires a physiological buffer rather than bacteriostatic water, or the peptide aggregates in acidic solutions (BAC is slightly acidic). Use BAC (Benzyl Alcohol 0.9%) when: the reconstituted peptide needs to be stored for days to weeks at 2-8°C, as benzyl alcohol provides bacteriostatic protection. For very acidic peptides (GHRH analogues), use dilute acetic acid (0.1-0.6%) as the primary reconstitution vehicle, then dilute with PBS or BAC.
Yes, in cell biology applications. Standard PBS without Ca²⁺/Mg²⁺ is used for cell detachment (trypsinization) because Ca²⁺ and Mg²⁺ interfere with trypsin activity and cell-surface EDTA chelation. PBS with Ca²⁺ (0.9 mM) and Mg²⁺ (0.49 mM) is used for maintaining cell attachment and for some signaling studies where divalent cations are required. Our PBS is Ca²⁺/Mg²⁺-free (standard formulation).
Our PBS is tested by Limulus Amebocyte Lysate (LAL) assay to ≤0.1 EU/mL, suitable for use as injection vehicle in rodent studies and as reagent in immunological assays sensitive to endotoxin contamination.
PBS can be autoclaved (121°C, 15 min) — phosphate buffers are thermostable, though prolonged autoclaving can shift pH slightly due to phosphate speciation changes. Sterile filtration (0.2 µm) is preferred for maintaining precise composition. Our PBS is supplied sterile-filtered and endotoxin-tested.
For laboratory research use only. Not for human or veterinary use. PeptidesFromChina.co is a B2B wholesale supplier operating under strict research-use-only terms. All products are sold exclusively for in vitro and preclinical research purposes.