| Field | Specification |
|---|---|
| Target | |
| Alternative names | Acetylsalicylic acid; ASA |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C9H8O4 |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
Aspirin, also known as Acetylsalicylic acid or ASA, is an orally active, potent, irreversible inhibitor of cyclooxygenase COX-1 and COX-2, with IC50 values of 5 and 210 μg/mL, respectively. It induces apoptosis, inhibits the activation of NF-κB, and also inhibits platelet prostaglandin synthetase, and can help prevent coronary artery and cerebrovascular thrombosis[1][2][3][4][5][6]. It is supplied as a white to off-white solid (C9H8O4, MW 180.16) at 99.87% purity.
Physical & Chemical Properties
| CAS Number | 50-78-2 |
|---|---|
| Molecular Formula | C9H8O4 |
| Molecular Weight | 180.16 g/mol |
| Purity | 99.87% |
| Appearance | Solid |
| Color | White to off-white |
| SMILES | OC(C1=C(OC(C)=O)C=CC=C1)=O |
| Target | COX-1, COX-2 |
| Signaling Pathway | Apoptosis; MAPK/ERK Pathway; NF-κB; Anti-infection; Autophagy; Immunology/Inflammation |
| Solubility | In Vitro: DMSO: 100 mg/mL (555.06 mM; Requires sonication; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO) H2O: 3.12 mg/mL (17.32 mM; Requires sonication and warming and heat to 37°C) |
| Storage | Powder: -20°C, 3 years; 4°C, 2 years. In solvent: -80°C, 2 years; -20°C, 1 year. |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Biological Activity
IC50 & Target[1]
|
COX-1 27.75 μM (IC50) |
COX-2 1.17 mM (IC50) |
Literature Cited
Sources cited in this description and in the In Vitro & In Vivo Data tab. Peer-reviewed publications that used this product are listed under References.
[6]. Elwood PC, et al. Aspirin, salicylates, and cancer. Lancet. 2009 Apr 11;373(9671):1301-9.
Safety
For Research Use Only. Not for use in diagnostic or therapeutic procedures, and not for human or veterinary use. Handle in accordance with the Safety Data Sheet and your institution's chemical hygiene plan.
In Vitro
| Solvent | Solubility | Notes |
|---|---|---|
| DMSO | 100 mg/mL (555.06 mM) | requires sonication; use freshly opened DMSO (absorbed moisture lowers solubility) |
| H2O | 3.12 mg/mL (17.32 mM) | requires sonication and warming and heat to 37°C |
Aliquot the stock solution and store it at -80°C (up to 2 years) or -20°C (up to 1 year); avoid repeated freeze-thaw cycles.
If water is used as the stock solvent, dilute to the working solution and sterilize it through a 0.22 μm filter before use.
In Vivo
Choose the formulation that suits the animal model and route of administration; percentages are volume ratios of the final working solution. Start from a clear DMSO stock (see In Vitro above), add the co-solvents one at a time in the order listed, mixing after each addition, and prepare the working solution fresh on the day of dosing. If precipitation or phase separation occurs, gentle warming or sonication can help.
Protocol 1
| Composition | 10% DMSO + 40% PEG300 + 5% Tween-80 + 45% saline |
|---|---|
| Result | ≥ 2.5 mg/mL (13.88 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.5 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (25.0 mg/mL) to 400 μL PEG300; then 50 μL Tween-80; then 450 μL saline to bring the volume to 1 mL. Saline: dissolve 0.9 g sodium chloride in ddH2O and make up to 100 mL. |
Protocol 2
| Composition | 10% DMSO + 90% (20% SBE-β-CD in saline) |
|---|---|
| Result | ≥ 2.5 mg/mL (13.88 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.5 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (25.0 mg/mL) to 900 μL 20% SBE-β-CD in saline. 20% SBE-β-CD in saline: dissolve 2 g SBE-β-CD powder in 10 mL saline until clear (4°C, store up to one week). |
Protocol 3
| Composition | 10% DMSO + 90% Corn Oil |
|---|---|
| Result | ≥ 2.5 mg/mL (13.88 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.5 mg/mL (saturation not determined). Use with caution if continuous dosing will exceed two weeks. For 1 mL of working solution: add 100 μL DMSO stock (25.0 mg/mL) to 900 μL corn oil. |
Direct preparation of the working solution
These formulations are prepared directly, without a DMSO stock; use them promptly after preparation.
Protocol 4
| Composition | saline |
|---|---|
| Result | 5 mg/mL (27.75 mM); clear solution; requires sonication |
Protocol 5
| Composition | 50% PEG300 + 50% saline |
|---|---|
| Result | 5 mg/mL (27.75 mM); clear solution; requires sonication |
Data provided by the manufacturer.
In Vitro
In human articular chondrocytes, Aspirin inhibits COX-1 (IC50 = 3.57 μM) and COX-2 (IC50 = 29.3 μM)[2]. By acetylating serine-530 of COX-1, Aspirin blocks thromboxane A synthesis in platelets and reduces platelet aggregation[3]. Aspirin inhibits COX-2 protein expression by blocking the binding of CCAAT/enhancer binding protein beta (C/EBPbeta) to the cognate site in the COX-2 promoter/enhancer[3]. In transfected T cells, Aspirin blocks NF-κB-dependent transcription driven by the lgκ enhancer and by the long terminal repeat (LTR) of the human immunodeficiency virus (HIV)[4]. Aspirin induces apoptosis through caspase activation, p38 MAP kinase activation, release of mitochondrial cytochrome c, and activation of the ceramide pathway[6].
In Vivo
| Animal Model | Male albino Charles River rats (200-250 g, 8 animals/group, fever was induced by 20 mL/kg of a 20% aqueous suspension of brewer’s yeast which was injected SC in the back below the nape of the neck)[7] |
|---|---|
| Dosage | 5, 25, 50, 100 and 150 mg/kg |
| Administration | PO, once |
| Result | Produced a statistically significant decrease of 0.23°C at 15 min post-drug at the dose of 150 mg/kg. Antipyretic effect gradually increased in magnitude until a peak effect of 1.96 °C was reached at 120 min post-drug. The ED50 of aspirin was found to be 10.3 mg/kg with confidence limits of 1.8-23.0 mg/kg. The antipyretic response to aspirin is dependent on the dose of the compound administered. |
| Animal Model | Albino male mice [8] |
|---|---|
| Dosage | 500 mg/kg, single dose |
| Administration | oral |
| Result | Caused erosion of the surface epithelial cells. Resulted in a decrease in the mucosal thickness. Induced ulcer without COX-1 reaction. |
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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