Hubbry Logo
Nonidet P-40Nonidet P-40Main
Open search
Nonidet P-40
Community hub
Nonidet P-40
logo
7 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Nonidet P-40
Nonidet P-40
Nonidet P-40
View on Wikipedia
from Wikipedia

Nonidet P-40 is a nonionic, non-denaturing detergent. Its official IUPAC name is octylphenoxypolyethoxyethanol.

Nonidet P-40 is sometimes abbreviated as NP-40, but should not be confused with a different detergent by the same name NP-40, nonylphenoxypolyethoxyethanol of the Tergitol NP series of Dow Chemicals.

Nonidet was a trademark of Shell Chemical Co. from 1956 to the early 2000s,[1][2] but they no longer make it.[3]

Nonidet P-40 is no longer sold by the chemical company Sigma-Aldrich. Sigma-Aldrich has replaced Nonidet P-40 with IGEPAL CA-630, which is described as a "nonionic, non-denaturing detergent". Sigma-Aldrich claims that IGEPAL CA-630 is "chemically indistinguishable from Nonidet P-40".

IGEPAL consists of octyl-phenoxy(polyoxyethylene)ethanol. Tergitol and the Sigma and BioChemica Nonidet P40 substitute detergents consist of nonyl-phenyl-polyethylene glycol. The original Shell Nonidet P-40 consisted of octyl-phenoxy(polyoxyethylene)ethanol, making IGEPAL the most comparable of the four substitutes.[3]

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Nonidet P-40

View on Grokipedia
from Grokipedia
Nonidet P-40, commonly abbreviated as , is a nonionic, non-denaturing and originally developed by Shell Chemical Company as a for a of polyoxyethylene (9-10) octyl phenyl ethers, chemically known as (octylphenoxy)polyethoxyethanol, with an average molecular weight of 680 g/mol and a (CMC) of 0.059 mM at 25°C. It functions by disrupting bilayers through formation, enabling the extraction and solubilization of proteins and without denaturing them, which is essential for maintaining in downstream applications. Widely utilized in cell buffers for techniques such as , Western blotting, and assays, Nonidet P-40 has been a staple in biochemical research since the mid-20th century (introduced in 1956) due to its mild action. However, production of the original formulation by Shell ceased around 2002 for environmental reasons related to its ethoxylate () components, which are persistent and endocrine-disrupting in aquatic environments, leading to the adoption of substitutes such as Igepal CA-630 or other equivalent octylphenol ethoxylates that replicate its properties, including a similar CMC range of 0.05-0.3 mM and molecular formula approximating C32H58O10 for n=9 units. These substitutes ensure continued utility in protocols requiring gentle permeabilization, such as intracellular polymerization assays and studies, where Nonidet P-40 enhances without .

Properties

Chemical Structure and Composition

Nonidet P-40, also known as Igepal CA-630 in its substitute form, is chemically classified as an ethoxylated octylphenol, a non-ionic surfactant with the official IUPAC name octylphenoxypolyethoxyethanol. Its molecular structure consists of a hydrophobic octylphenyl group—a linear eight-carbon alkyl chain (C₈H₁₇) attached to a phenolic ring—linked via an oxygen atom to a hydrophilic polyoxyethylene chain, represented as -O-(CH₂CH₂O)ₙ-H, where n approximates 9-10 units. This can be visualized as: CH₃(CH₂)₇-C₆H₄-O-(CH₂CH₂O)ₙ-H, emphasizing the amphiphilic nature with the lipophilic tail and the solvating oligomer. The general for Nonidet P-40 is C₁₄H₂₂O(C₂H₄O)ₙ, reflecting the C₁₄ base from the octylphenol moiety and the variable . For the typical composition with n = 9, the formula expands to approximately C₃₂H₅₈O₁₀, yielding an average molecular weight of about 603 Da. Variations in the exact number of units (typically 8.5-9.5) arise from the manufacturing process, which involves reacting octylphenol with , resulting in a polydisperse mixture rather than a single compound. Nonidet P-40 is distinctly octyl-based (C₈ alkyl chain), setting it apart from similar nonylphenol ethoxylates such as the series, which employ a nine-carbon (C₉) alkyl chain and thus have a C₁₅H₂₄O base formula with higher hydrophobicity and different HLB values. This structural difference influences and application specificity, though both are polyethoxylated alkylphenols. The original Nonidet P-40 features an unbranched alkyl chain, whereas modern substitutes like Igepal CA-630 introduce slight branching for equivalent performance.

Physical and Chemical Properties

Nonidet P-40 appears as a clear, at . It exhibits high in and most organic solvents, enabling its use in aqueous and mixed systems. Above its (CMC) of approximately 0.059 mM at 25°C, it forms micelles that facilitate solubilization without disrupting molecular interactions. As a non-ionic , Nonidet P-40 is non-denaturing, preserving the native structure of proteins during solubilization processes. Its hydrophile-lipophile balance (HLB) value of approximately 13.5 supports effective emulsification in oil-in-water systems. The compound demonstrates stability consistent with its application in buffered solutions. Nonidet P-40 has a of about 1.06 g/mL at 20°C and a exceeding 200°C, contributing to its low volatility under standard conditions. These properties ensure it remains in solution during typical experimental manipulations without significant .

History and Production

Development and Manufacturing

Nonidet P-40 was developed as part of the Nonidet series of non-ionic detergents by Shell Chemical Company, with the trademark registered in 1956 for use in chemical substances including surfactants. The product emerged during the post-World War II expansion of the synthetic surfactant market, which saw increased demand for efficient detergents in industrial applications following the shift from soap-based to synthetic formulations in the 1940s and 1950s. The manufacturing process involved ethoxylation of octylphenol, where the phenolic compound reacts with 9-10 moles of ethylene oxide to form the polyoxyethylene chain, typically under base-catalyzed conditions using potassium hydroxide (KOH) or similar catalysts at elevated temperatures around 120-180°C. This reaction produces an anhydrous liquid nonionic surfactant with a consistent average degree of ethoxylation, ensuring uniform solubility and emulsifying properties essential for its applications. Shell's original Nonidet P-40 was commercially available from the mid-20th century, positioning it as a key player in the burgeoning industrial detergent sector driven by advancements in petrochemical-derived surfactants. Quality specifications emphasized a precise polyoxyethylene chain length averaging 9-10 units, which distinguished the authentic Shell product from later variable substitutes by providing reproducible performance in formulations.

Discontinuation and Substitutes

Shell Chemical Company phased out production of Nonidet P-40 in the early . This discontinuation was driven primarily by environmental concerns over the persistence and toxicity of degradation products from ethoxylates, such as octylphenol, aligning with regulatory pressures including REACH restrictions on these compounds. Octylphenol ethoxylates, while not explicitly listed under a specific Annex XVII entry like nonylphenol ethoxylates (Entry 46a), are subject to REACH authorization and phase-out due to their potential to bioaccumulate and disrupt endocrine systems in aquatic organisms. The mandated a phase-out of ethoxylates in most applications by January 2021. As chemically identical alternatives, Igepal CA-630—originally produced by and now part of Syensqo—offers the same octylphenoxypolyethoxyethanol composition and performance characteristics. Other substitutes include the Tergitol NP-series from Dow Chemical, which are nonylphenol-based variants with a slightly lower (HLB) of 12.9 compared to Nonidet P-40's 13.5. Today, Nonidet P-40 is available through suppliers like and under labels such as "Nonidet P-40 Substitute," often with CAS number 9002-93-1 for reformulated versions. These products may require minor protocol adjustments, as 2017 research demonstrated that common substitutes like Igepal CA-630 and Tergitol are approximately 10-fold more potent in intracellular signaling and assays, necessitating dilutions to match original efficacy. In research contexts, protocols developed from the 1960s through the 2000s frequently referred to "NP-40" as a shorthand for Nonidet P-40, and contemporary substitutes preserve its non-denaturing properties for applications like membrane protein solubilization when properly titrated.

Applications

Biochemical and Molecular Biology Uses

Nonidet P-40, a non-ionic detergent, plays a key role in biochemical and molecular biology protocols by enabling the solubilization of cellular components while maintaining protein integrity. It is particularly valued for its ability to disrupt plasma and nuclear membranes during cell lysis, facilitating the extraction of both soluble and membrane-bound proteins for downstream analyses. This property makes it a staple in buffers like RIPA (radioimmunoprecipitation assay), where it is typically included at 1% concentration alongside ionic detergents to achieve comprehensive cell disruption without excessive protein denaturation. In cell lysis applications, Nonidet P-40 is commonly used at 0.5-1% in lysis buffers to solubilize proteins effectively, as seen in standard protocols for preparing total cell extracts. This concentration allows for the isolation of integral proteins while preserving their native structure, and it is often combined with protease inhibitors to prevent degradation during extraction. Unlike milder detergents such as , which selectively permeabilize the plasma without disrupting nuclear or membranes, Nonidet P-40 enables of nuclear membranes, yielding more complete protein recovery for techniques requiring whole-cell lysates. For (IP) and co-immunoprecipitation (co-IP), Nonidet P-40 facilitates the extraction of protein complexes from lysed cells by maintaining native interactions through its non-denaturing action. Buffers containing 0.5-1% Nonidet P-40, such as those with 50 mM Tris-HCl (pH 7.5) and 100-150 mM NaCl, are widely employed to lyse cells prior to pull-down, ensuring the stability of multiprotein assemblies for analysis. This approach has been instrumental in studies of protein-protein interactions, including those involving cytoskeletal elements. In western blotting and , Nonidet P-40 aids by cells to release proteins for separation and immunoblotting. It is typically incorporated at 1% in non-denaturing buffers to extract proteins from membrane fractions, followed by denaturation steps, allowing detection of targets like phosphorylated proteins or isoforms. This method supports high-yield protein recovery suitable for quantitative analysis. Nonidet P-40 is employed in assays to isolate polymerized in studies, where 1% concentrations in buffers selectively solubilize non-polymerized fractions, enabling quantification of dynamics. A study evaluated commercial substitutes for discontinued Nonidet P-40 in these assays, titrating their activities to confirm equivalence in screening microtubule-targeting agents, highlighting its ongoing despite formulation changes. Typical working concentrations of Nonidet P-40 range from 0.1-2% v/v in biochemical assays, with lower levels (0.1-0.5%) suiting gentle extractions and higher (1-2%) for robust . It is compatible with and inhibitors, enhancing protocol flexibility in protein stabilization.

Industrial and Other Applications

Nonidet P-40, also known as Igepal CA-630, served as a nonionic in various , particularly where emulsification and properties were required. In the paints and coatings sector, it functioned as a stabilizer in water-based formulations, enhancing pigment dispersion and stability to improve coating performance and . In and processing, Nonidet P-40 acted as a agent and , facilitating , , and aqueous processing by reducing and promoting uniform penetration of solutions into fibers or pulp. Its compatibility with aqueous systems made it suitable for scouring and finishing operations in these industries. For agrochemical applications, Nonidet P-40 was incorporated into pesticide and herbicide formulations as an emulsifier, improving the solubility of active ingredients in water and enhancing their spreading and adhesion on plant surfaces for better efficacy. Beyond these primary uses, Nonidet P-40 performed as a demulsifier in oil-water separation processes, aiding the breakdown of emulsions in industrial wastewater treatment or petroleum refining. Historically, prior to its phase-out in the early 2000s due to environmental regulations, it was utilized in household cleaners and detergents for its controlled foaming and cleaning properties. However, ongoing environmental regulations continue to limit their use; for example, as of January 1, 2025, alkylphenol ethoxylates are restricted to ≤1000 ppm in laundry detergents in Washington State, USA. In , sales of octylphenol ethoxylates in the coatings market reached approximately 22,700 metric tons, indicating their scale in industrial applications prior to phase-out.

Safety and Environmental Concerns

Health and Toxicity

Nonidet P-40 is classified as a mild skin and eye irritant under the Globally Harmonized System (GHS), specifically in Category 2 for both skin irritation and serious eye irritation, indicating potential for reversible effects upon direct contact. It is not classified as acutely toxic, with an oral LD50 greater than 2000 mg/kg in rats, suggesting low immediate systemic risk from ingestion. Chronic exposure to Nonidet P-40 exhibits low systemic , with no evidence of carcinogenicity, , or target organ damage reported in available assessments. However, repeated contact may lead to allergic reactions, classified as a potential skin sensitizer under GHS. Safe handling of Nonidet P-40 requires the use of protective gloves and to prevent from splashes or prolonged contact, along with avoiding inhalation of aerosols or mists in environments. Its non-ionic nature contributes to relatively lower potential compared to ionic . In biomedical applications, Nonidet P-40 is non-toxic to proteins at typical working concentrations of 0.1% to 1%, preserving native structure and function during cell lysis and extraction without denaturation. No has been reported, with in vitro tests showing no mutagenic effects. There is no specific (PEL) established by OSHA for Nonidet P-40; general ventilation is recommended for industrial or use to minimize airborne exposure.

Regulatory and Ecological Impact

Nonidet P-40, classified as an octylphenol ethoxylate (OPE) under CAS number 9036-19-5, is subject to regulatory scrutiny due to its environmental persistence and potential for degradation into octylphenol, a . In the , OPEs are included on REACH Annex XIV as substances of very high concern (SVHCs), requiring for manufacture or use after the sunset date of January 4, 2021, with exemptions for scientific , development, and use as process chemicals in closed systems. Certain applications, such as in textiles and cleaning products, face phase-out under broader alkylphenol ethoxylate (APE) measures to prevent aquatic releases. These controls, implemented progressively since 2013, have significantly reduced OPE use in the EU. In the United States, while the Environmental Protection Agency (EPA) has prioritized nonylphenol ethoxylates (NPEs) for TSCA risk evaluation and proposed a Significant New Use Rule (SNUR) in 2023 (not finalized as of November 2025) for specific NPEs, octylphenols share similar PBT properties and are monitored under general chemical assessments, though no dedicated SNUR exists for OPEs. Related APEs were added to the Toxics Release Inventory (TRI) in 2016 for tracking releases. Some U.S. states, including , impose limits on APEs in consumer products like laundry detergents (e.g., below 0.05% by weight). Globally, analogous restrictions apply, such as Taiwan's phased import bans on detergents containing alkylphenol ethoxylates, announced in June 2025 and effective from December 2026 for concentrations above 5% by weight, extending to 0.1% by June 2027. Following the original product's discontinuation, current formulations or substitutes require compliance with these authorizations in the EU as of 2025. Ecologically, Nonidet P-40 and other OPEs pose significant risks to aquatic ecosystems primarily through their into octylphenol (OP), a persistent, bioaccumulative, and toxic (PBT) compound that acts as an . OP has been detected in surface waters, sediments, and aquatic biota worldwide, with concentrations often exceeding standards in regions with high industrial discharge. Studies indicate that exposure to OP at low concentrations (e.g., 10-100 μg/L) induces in male , such as vitellogenin induction and conditions in species like fathead minnows, leading to reduced and declines. OPEs themselves are acutely toxic to aquatic organisms, with data sheets classifying Nonidet P-40 as very toxic to aquatic life (H400) and harmful with long-lasting effects (H412 or H411), based on LC50 values for and typically below 10 mg/L. Chronic exposure disrupts microbial communities in and inhibits algal growth, further exacerbating trophic imbalances in freshwater and marine environments. Due to these impacts, precautionary measures in product labels emphasize avoiding environmental release, and substitutes like alkyl polyglucosides are recommended to mitigate ongoing ecological harm.

References

  1. https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/186/820/detergents-guide-ms.pdf
  2. https://pubmed.ncbi.nlm.nih.gov/28177759/
  3. https://bitesizebio.com/42039/will-the-real-np-40-please-stand-up-chemical-nomenclature-woes/
  4. https://anatrace.com/en/product/NIDP40-500-ML
  5. https://www.epa.gov/sites/default/files/2015-09/documents/rin2070-za09_np-npes_action_plan_final_2010-08-09.pdf
  6. https://cdnsciencepub.com/doi/10.1139/bcb-2016-0141
  7. https://www.sciencedirect.com/science/article/abs/pii/S0006291X19304292
  8. https://www.interchim.fr/ft/W/WZ7550.pdf
  9. https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/product/documents/143/963/11332473001bul.pdf
  10. https://www.sigmaaldrich.com/US/en/sds/Roche/11754599001
  11. https://www.atamanchemicals.com/tergitol-np-40_u28075/
  12. https://pubmed.ncbi.nlm.nih.gov/8032310/
  13. https://www.fishersci.com/shop/products/nonidet-p40-substitute-ultrapure-thermo-scientific/AAJ19628AP
  14. https://cdn.moleculardimensions.com/public/1771/NONIDET-P40-SUBSTITUTE-%28NIDP40%29-SDS.pdf
  15. https://vtechworks.lib.vt.edu/bitstream/handle/10919/11174/Brian2.pdf?sequence=3
  16. https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/product/documents/110/796/11754599001bul.pdf
  17. https://echa.europa.eu/hot-topics/alkylphenols
  18. https://www.sigmaaldrich.com/US/en/product/sigma/i8896
  19. https://www.bostonbioproducts.com/products/ripa-buffer-bp-115
  20. https://cshprotocols.cshlp.org/content/2010/8/pdb.prot5466.full.pdf
  21. https://pmc.ncbi.nlm.nih.gov/articles/PMC1084301/
  22. https://advansta.com/detergent-lysis-buffer/
  23. https://pmc.ncbi.nlm.nih.gov/articles/PMC4678309/
  24. https://pmc.ncbi.nlm.nih.gov/articles/PMC2785659/
  25. https://pmc.ncbi.nlm.nih.gov/articles/PMC6359974/
  26. https://pmc.ncbi.nlm.nih.gov/articles/PMC2719404/
  27. https://www.bio-rad-antibodies.com/western-blotting-sample-preparation.html
  28. https://azelishic-us.com/shop/igepal-ca-630/
  29. https://www.ulprospector.com/en/na/Cleaners/Detail/918/81277/IGEPAL-CA-630
  30. https://www.stepan.com/content/stepan-dot-com/en/products-markets/product/IGEPALCA630.html
  31. https://www.bocsci.com/product/nonidet-p-40-cas-9016-45-9-37063.html
  32. https://ecology.wa.gov/waste-toxics/reducing-toxic-chemicals/washingtons-toxics-in-products-laws/safer-products/compliance-and-reporting
  33. https://www.pcimag.com/articles/91697-alkylphenol-ethoxylate-free-sulfates-in-emulsion-polymerization
  34. https://www.chemscience.com/assets/uploads/safety_datasheet/GRM2352-sds.pdf
  35. https://cdn.gbiosciences.com/pdfs/msds/786-512_msds.pdf
  36. https://www.cytoskeleton.com/pdf-storage/msds/bk128.pdf
  37. https://www.sigmaaldrich.com/US/en/sds/sigma/np40
  38. https://pmc.ncbi.nlm.nih.gov/articles/PMC9432755/
  39. https://echa.europa.eu/authorisation-list
  40. https://www.epa.gov/assessing-and-managing-chemicals-under-tsca/risk-management-nonylphenol-and-nonylphenol-ethoxylates
  41. https://www.moenv.gov.tw/en/news/press-releases/33136.html
  42. https://www.sciencedirect.com/science/article/abs/pii/S0160412008000081
  43. https://www.lobachemie.com/lab-chemical-msds/MSDS-NONIDET-P40-CASNO-9016-45-5037D-EN.aspx
  44. https://www.epa.gov/assessing-and-managing-chemicals-under-tsca/fact-sheet-nonylphenols-and-nonylphenol-ethoxylates
Add your contribution
Related Hubs
User Avatar
No comments yet.