Chemical Identity and Structure

1,2-Dipalmitoyl-sn-glycero-3-phosphopropanol (sodium salt) belongs to the class of diacylglycerophosphate lipids in which the canonical phosphate head group is esterified with propan-1-ol rather than the more common choline, ethanolamine, or serine moieties. The glycerol backbone carries two palmitoyl (hexadecanoyl, C16:0) ester-linked acyl chains at the sn-1 and sn-2 positions, conferring high conformational order and a relatively elevated gel-to-liquid-crystalline phase-transition temperature characteristic of saturated dipalmitoyl lipids. The sodium counterion renders the molecule water-dispersible and contributes to the net negative charge at physiological pH, making it a true anionic phospholipid.

The propanol head group distinguishes this compound from the structurally analogous 1,2-Dipalmitoyl-sn-glycero-3-phosphate (DPPA), introducing a short alkyl spacer between the phosphate oxygen and the terminal hydroxyl. This modification subtly alters inter-headgroup hydrogen-bonding geometry and electrostatic surface potential in bilayer assemblies, providing researchers with a structurally defined tool to probe head-group effects on membrane organisation.

Handling, Reconstitution, and Storage

Receipt and Inspection: Upon receipt, visually inspect the vial for integrity. The compound is typically supplied as a white to off-white powder or film. Record the lot number and confirm that the vial has been maintained at the recommended cold-chain temperature during shipment.

Storage: Store at −20 °C in a tightly sealed vial under an inert gas (nitrogen or argon) blanket. Protect from light and moisture at all times. Phospholipids are susceptible to oxidative degradation and hydrolysis of the ester bonds; proper storage conditions are essential to maintain purity and biological relevance of experimental results. For long-term storage beyond six months, confirm purity by thin-layer chromatography (TLC) or HPLC before use.

Reconstitution: Dissolve the lipid in an appropriate organic solvent such as chloroform, chloroform/methanol mixtures (e.g., 2:1 v/v), or other halogenated solvents suitable for phospholipids. Avoid prolonged exposure to protic solvents without an inert atmosphere. When preparing aqueous dispersions for biological assays, use extrusion or bath sonication to form unilamellar vesicles. Allow the lipid film to fully hydrate above the phase-transition temperature to ensure homogeneous bilayer formation.

Safety: Handle in a well-ventilated fume hood when using chloroform-based solvents. Consult the Safety Data Sheet (SDS) for complete hazard information and personal protective equipment (PPE) requirements.

Research Applications

Model Membrane Systems: The well-defined saturated acyl chains of this lipid make it a valuable component in constructing model lipid bilayers—including supported lipid bilayers and giant unilamellar vesicles (GUVs)—where high bilayer order and low fluidity are experimentally desirable. By blending it with unsaturated or zwitterionic lipids, researchers can tune membrane phase behaviour and lateral organisation.

Electrostatic Studies: The negatively charged phosphopropanol head group enables investigation of electrostatic interactions at the bilayer interface, including cation binding, lipid–protein interaction studies, and the influence of surface charge density on membrane-associated enzyme activity or peptide adsorption.

Liposome Formulation Research: Anionic phospholipids with saturated chains are explored as components of stealth and targeted liposomal drug delivery systems due to their contribution to bilayer rigidity and surface charge modulation. This compound serves as a chemically defined reference or functional lipid in such formulation studies.

Biophysical Characterisation: Differential scanning calorimetry (DSC), X-ray diffraction, and solid-state NMR can be applied to characterise the thermotropic phase behaviour of bilayers incorporating this lipid, providing insight into head-group geometry effects distinct from those observed with DPPA or DPPG.

Quality Considerations and Purity Verification

For rigorous biophysical or formulation studies, researchers should verify lipid purity before use. Recommended analytical methods include:

• Thin-Layer Chromatography (TLC): Run on silica gel plates using a chloroform/methanol/water solvent system; visualise with iodine vapour or molybdenum blue spray reagent. A single spot confirms lipid integrity.
• HPLC (ELSD or CAD detection): Reverse-phase or normal-phase HPLC with evaporative light-scattering or charged aerosol detection provides quantitative purity assessment and detects lyso-lipid and free fatty acid impurities.
• Mass Spectrometry (MS): Electrospray ionisation MS (ESI-MS) confirms molecular identity and detects acyl chain hydrolysis products.
• Phosphorus Assay: The Bartlett or Stewart phosphorus assay can be used to quantify total lipid phosphorus content for accurate stock concentration determination.

Discard any batch exhibiting a yellow or brown discolouration, which indicates oxidative degradation, or showing multiple spots by TLC.

Regulatory and Ordering Information

1,2-Dipalmitoyl-sn-glycero-3-phosphopropanol (sodium salt) is supplied by Aladdin Scientific as a research-grade reagent under SKU D130565. It is intended for laboratory research use only and is not approved for use in humans, animals, or clinical diagnostics.

Researchers requiring certificates of analysis (CoA), safety data sheets (SDS), or additional technical documentation should contact Aladdin Scientific customer service or download directly from the product page. Bulk quantities and custom purity specifications may be available upon request.

When ordering, reference SKU D130565 to ensure receipt of the correct sodium salt form. Confirm storage requirements with your institution's chemical inventory management system to ensure compliant handling from delivery through disposal.