Lipid; DSPC does not bind to a specific pharmacological target like a receptor or enzyme. Instead, it functions as a structural excipient, forming the lipid bilayer matrix of drug delivery vehicles such as liposomes and LNPs. It can co-assemble with other lipids to create stable liposomal membranes.
DSPC does not have a specific biological receptor target. As a structural lipid, it functions by forming stable bilayers and liposomes, providing membrane integrity and stability to lipid-based drug delivery systems.

DSPC-cholesterol is found in the outer layer of empty lipid nanoparticle (LNP) systems without siRNA, but some of it is internalized with siRNA in loaded systems [2].

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DSPC itself is not a pharmacologically active compound; therefore, it does not exhibit traditional "in vitro activity" such as enzyme inhibition. Its role in vitro is as a formulation component. For instance, DSPC-based liposomes, especially when combined with cholesterol and PEGylated lipids, have been shown to have high encapsulation efficiency for various drugs and to improve serum stability. DSPC liposomes prepared with the ammonium sulfate gradient method demonstrated efficient drug-to-lipid ratios and enhanced stability.

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In vitro, DSPC is used to synthesize liposomes and LNPs. In empty LNP systems that do not contain siRNA, DSPC-cholesterol resides in outer layers, whereas in loaded systems, a portion of the DSPC-cholesterol is internalized together with siRNA. DSPC enhances encapsulation efficiency and liposome stability. It can be used to formulate liposomes for drugs like daunorubicin and irinotecan.

As an excipient, DSPC is essential for enhancing the in vivo performance of encapsulated drugs. Studies on liposomal formulations containing DSPC have shown improved pharmacokinetics and enhanced antitumor efficacy when used to deliver therapeutic payloads, while also mitigating associated side effects. Additionally, DSPC-Azo liposomes co-encapsulated with upconverting nanoparticles (UCNPs) successfully inhibited tumor growth in a 4T1 tumor-bearing mouse model under near-infrared (NIR) irradiation. The physical properties of DSPC bilayers (e.g., high bending rigidity and membrane thickness) contribute to its stability in biological environments.

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RNA interference (RNAi) therapeutics appear to offer substantial opportunities for future therapy. However, post-administration RNAi effectors are typically unable to reach disease target cells in vivo without the assistance of a delivery system or vector. The main focus of this review is on lipid-based nanoparticle (LNP) delivery systems in current research and development that have at least been shown to act as effective delivery systems for functional delivery of RNAi effectors to disease target cells in vivo. The potential utility of these LNP delivery systems is growing rapidly, and LNPs are emerging as the preferred synthetic delivery systems in preclinical studies and current nonviral RNAi effector clinical trials. Moreover, studies on LNP-mediated delivery in vivo are leading to the emergence of useful biophysical parameters and physical organic chemistry rules that provide a framework for understanding in vivo delivery behaviors and outcomes. These same parameters and rules should also suggest ways and means to develop next generations of LNPs with genuine utility and long-term clinical viability[1].

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DSPC-containing liposomes and LNPs are used for drug delivery applications in vivo. The high phase transition temperature of DSPC contributes to the stability of lipid carriers in circulation, making it a key component in liposomal formulations and mRNA vaccine platforms. Studies have shown that DSPC-based liposomes can improve drug retention and reduce toxicity compared to traditional formulations.

Specific enzyme/receptor binding protocols for DSPC are not applicable, as it does not function as an active drug compound. However, analytical protocols exist to characterize its purity and identity. For quality control, high-performance liquid chromatography coupled with evaporative light scattering detection (HPLC-ELSD) or mass spectrometry (LC-MS) is typically used. The purity of research-grade DSPC is generally ≥99%.

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DSPC liposome formation involves dissolving DSPC with other lipids in organic solvent (e.g., chloroform), drying to form a lipid film, and hydrating with aqueous buffer. The resulting liposomes are extruded through polycarbonate membranes to achieve uniform size. Particle characterization includes dynamic light scattering for size and zeta potential measurements. DSPC is typically stored dry, in the dark, at -20°C.

Traditional cell-based viability or proliferation assays are not standard for DSPC alone, as it is non-toxic and serves as a delivery vehicle. However, it is commonly included as a control or carrier in cell studies. Typically, DSPC/cholesterol liposomes are prepared via thin-film hydration followed by extrusion to achieve a defined size (e.g., ~100 nm). These liposomes are then added to cell cultures (e.g., HepG2, HEK293) to assess the delivery efficiency of encapsulated cargos or to evaluate cell uptake, without intrinsic induction of cytotoxicity.

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Cellular uptake studies of DSPC-containing liposomes are performed using various cell lines (e.g., HeLa, HEK293T). Liposomes encapsulating fluorescent markers or therapeutic agents are added to cell cultures, and uptake is quantified by fluorescence microscopy, flow cytometry, or measuring the biological activity of encapsulated agents.

In a typical study involving DSPC-based formulations, specific-pathogen-free female mice (e.g., BALB/c or 4T1 tumor-bearing models) are used. Animals receive intravenous injections of DSPC liposomes loaded with therapeutic agents (e.g., doxorubicin or other anti-cancer drugs). For example, in a 4T1 tumor-bearing mouse model, DSPC-Azo liposomes co-encapsulated with upconverting nanoparticles (UCNPs) were administered via tail vein injection to evaluate antitumor efficacy under light irradiation.

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In vivo studies typically involve intravenous administration of DSPC-containing liposomal formulations in rodent models. Pharmacokinetic parameters such as circulation half-life, tissue distribution, and therapeutic efficacy are evaluated. DSPC-containing LNPs are used in preclinical studies for cancer therapy and vaccine delivery.

As a lipid carrier, DSPC significantly alters the pharmacokinetic profile of encapsulated drugs. For instance, PEGylated DSPC liposomes encapsulating amino acid conjugates demonstrated prolonged circulation time (improved half-life) and increased plasma exposure compared to the free drug. In LNP systems, DSPC-cholesterol is internalized together with siRNA payloads, facilitating delivery to target cells. Generally, DSPC is biodegradable and can be metabolized by endogenous phospholipases.

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DSPC contributes to the pharmacokinetic profile of liposomal formulations by providing membrane stability that prolongs circulation time. The high phase transition temperature (~55°C) reduces membrane permeability and drug leakage. DSPC is a key structural component in FDA-approved liposomal drugs.

DSPC is considered safe for pharmaceutical use and is Generally Recognized as Safe (GRAS) for pulmonary administration. Toxicological evaluations have shown negative results for genotoxicity and reproductive toxicity. In a range of inhalation toxicology studies, DSPC was not associated with significant adverse effects compared to controls. It is endogenous to the lungs, which contributes to its favorable safety profile. In cell-based studies, DSPC liposomes did not show significant cytotoxicity against normal cells, making it a reliable excipient for drug delivery systems.

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DSPC is generally recognized as safe (GRAS) and is used in pharmaceutical formulations. As a phospholipid, it is biocompatible and biodegradable. No significant toxicity has been reported for DSPC at concentrations used in drug delivery applications. DSPC is shipped under ambient temperature as a non-hazardous chemical.

[1]. Andrew D Miller. Delivery of RNAi therapeutics: work in progress. Expert Rev Med Devices. 2013 Nov;10(6):781-811.

[2]. On the role of helper lipids in lipid nanoparticle formulations of siRNA. Nanoscale. 2019 Nov 21;11(45):21733-21739.

1,2-Distearyl-sn-glycerol-3-phosphate choline is a phosphatidylcholine 36:0, in which both phosphatidyl groups are designated as stearoyl (octadecanoyl). It is functionally related to octadecanoic acid. PC (18:0/18:0) is a metabolite found or produced in Saccharomyces cerevisiae.

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DSPC (CAS 816-94-4) has the molecular formula C₄₄H₈₈NO₈P and a molecular weight of 790.15 g/mol. Its IUPAC name is (R)-2,3-bis(stearoyloxy)propyl (2-(trimethylammonio)ethyl) phosphate. Physicochemically, it is a white solid powder, insoluble in water but soluble in ethanol and DMSO (50 mg/mL). It is a cylindrical (conical) shaped lipid that tends to form stable bilayers in the gel phase at room temperature due to its high phase transition temperature (Tm) around 55°C. Storage recommendations: powder at -20°C for up to 2 years, protected from light.

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DSPC is widely utilized in lipid-based drug delivery systems including liposomal formulations and mRNA vaccine platforms. It is a component of FDA-approved Onpattro (patisiran) and mRNA COVID-19 vaccines. DSPC functions to enhance encapsulation efficiency and liposome stability. The purity is typically ≥98%.

C44H88NO8P

790.15

789.624

C, 66.88; H, 11.23; N, 1.77; O, 16.20; P, 3.92

816-94-4

1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d70;56952-01-3;1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d74;326495-38-9;1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d79;326495-39-0;1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d83;326495-40-3;1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d4;326495-35-6;1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d9;326495-36-7;1,2-Distearoyl-sn-glycero-3-phosphorylcholine-d13;326495-37-8

94190

Typically exists as white to off-white solids at room temperature

236 °C

13

0

8

44

54

888

1

[C@@H](COC(=O)CCCCCCCCCCCCCCCCC)(COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCCCCCCCCCCCCCCCC

NRJAVPSFFCBXDT-HUESYALOSA-N

InChI=1S/C44H88NO8P/c1-6-8-10-12-14-16-18-20-22-24-26-28-30-32-34-36-43(46)50-40-42(41-52-54(48,49)51-39-38-45(3,4)5)53-44(47)37-35-33-31-29-27-25-23-21-19-17-15-13-11-9-7-2/h42H,6-41H2,1-5H3/t42-/m1/s1

1,2-Distearoyl-sn-glycero-3-phosphocholine

1,2-Distearoyl-sn-glycero-3-PC; 1,2-Distearoyl-sn-glycero-3-phosphocholine; DSPC; Distearoyl phosphatidylcholine; (R)-2,3-Bis(stearoyloxy)propyl (2-(trimethylammonio)ethyl) phosphate; 1,2-dioctadecanoyl-sn-glycero-3-phosphocholine; PC(18:0/18:0); 1,2-Distearoyl-sn-3-phosphacholine;Coatsome MC 8080;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Ethanol: 12.5 mg/mL (15.82 mM)

Solubility in Formulation 1: 1.25 mg/mL (1.58 mM) in 10% EtOH + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear EtOH stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 1.25 mg/mL (1.58 mM) in 10% EtOH + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear EtOH stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 1.25 mg/mL (1.58 mM) (saturation unknown) in 10% EtOH + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear EtOH stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)