NameClozapine N-oxide (CNO) (water soluble)
Short descriptionWater soluble prototypical DREADD activator. Clozapine metabolite.
Clozapine N-oxide (CNO) is the prototypical chemical actuator for various DREADDs. It is a metabolite of the atypical antipsychotic clozapine.
‘Excitatory’ Gq- coupled) DREADDs:
CNO activates the excitatory Gq- coupled DREADDs: hM3Dq, hM1Dq and hM5Dq.
The hM3Dq DREADD is typically used for enhancing neuronal firing and activating (Gq- signaling in neuronal and non-neuronal cells.
‘Inhibitory’ (Gi- coupled) DREADDs:
CNO also activates the inhibitory hM4Di and hM2Di Gi-coupled DREADDs.
The hM4Di DREADD is the most commonly used inhibitory DREADD and is used for neuronal silencing.
Gs and β-arrestin coupled DREADDs:
CNO also activates the Gs- coupled DREADD (GsD) and the β-arrestin preferring DREADD: rM3Darr (Rq(R165L).
In the literature, CNO has been administered intraperitoneally (i.p.), subcutaneously, directly infused intracranially, via drinking water or osmotic mini-pump. See our Technical review (table 3) for example administration methods and doses.
Recent findings suggest that systemically administered CNO does not readily cross the blood-brain-barrier in vivo, and converts to clozapine which activates DREADDs. Care must be taken in experimental design and proper controls should be incorporated.
CNO dihydrochloride is now available.
Your technical review on CNO stability, solubility and use in the lab has been really helpful to my group. Verified customer
The Clozapine N-oxide (CNO) worked perfectly! It dissolved completely in saline at the dose I am using so no problems there! Verified customer, Istituto Italiano di Tecnologia
The clozapine N-oxide dissolves perfectly in saline, even at a high dose! Verified customer, Radboud University
Citations1 citation Submit Your Citation Now
Chemical name8-Chloro-11-(4-methyl-4-oxido-1-pip erazinyl)-5H-dibenzo[b,e][1,4]diazepine
Non-CNO DREADD activators
- Compound 21 (DREADD agonist 21) hydrochloride has minimal off-target activity and is not metabolized to clozapine. The freebase Compound 21 (DREADD agonist 21) is also available.
- The potent and selective hM3Dq DREADD agonist Perlapine hydrochloride (water soluble) and Perlapine are also available.
- Salvinorin B (SALB) Salvinorin B (SALB) which potently activates the inhibitory KORD DREADD to induce neuronal inhibition is also available.
Storing and Using Your Product
Storage instructionsRoom temperature (desiccate)
Solubility overviewSoluble in water (100mM), DMSO (100mM)
Due to the inherent chemical properties of CNO, this product requires careful handling – our guidelines are detailed below.
CNO has been shown in the literature to precipitate in solution and following further solubility studies that we have undertaken, we have found that precipitation occurred in some concentrated (100mM) samples of CNO dissolved in water.
When working with the compound, we therefore recommend:
- Make up solutions and use immediately if possible.
- Ensure that you are working in a dust free environment when preparing and handling solutions.
- Ensure that the product and solvents are at ambient temperature before preparing solutions. This means that you should allow the product to equilibrate to RT for at least one hour before opening and using.
- Please take care to ensure that your product is completely dissolved in your solution before use.
If you find precipitate in your solution, gently heat your solution in a water bath to approx 40°C and the compound should readily re-dissolve. Always take care to ensure that the compound is completely dissolved before use.
If you need to prepare stock solutions beforehand, you should aliquot out the solution into tightly sealed vials for storage. Storage of solutions should be at room temperature.
Our stability study showed that solutions of CNO remained stable for at least 4 weeks at room temperature. Always check that your product is completely dissolved before use; if precipitation is found follow the above steps. .
We recommend that you do not store solutions at temperatures below room temperature (i.e. +4°C/ -20°C) as we have found this is more likely to lead to precipitation of the compound.
For more information, read our review Clozapine N-Oxide (water soluble) - a technical review on stability, solubility and use in the lab. It includes data on solubility, storage and handling, including results from our in-house tests, and guidelines on use in the lab, in vivo and in vitro.
CNO dihydrochloride is now available. Our stability studies have not found this product to precipitate in solution.
ImportantThis product is for RESEARCH USE ONLY and is not intended for therapeutic or diagnostic use. Not for human or veterinary use.
References for Clozapine N-oxide (CNO) (water soluble)
Novel designer receptors to probe GPCR signaling and physiology.Wess et al (2013) Trends Pharmacol Sci. 34(7) : 385-92PubMedID: 23769625
Evolving the lock to fit the key to create a family of G protein-coupled receptors potently activated by an inert ligand.Arbruster et al (2007) Proc Natl Acad Sci U S A. 104(12) : 5163-8PubMedID: 17360345
The role of M1 muscarinic receptor agonism of N-desmethylclozapine in the unique clinical effects of clozapine.Weiner et al (2004) Psychopharmacology (Berl). 177(1-2) : 207-16PubMedID: 15258717
A chemical-genetic approach to study G protein regulation of beta cell function in vivo.Guettier et al (2009) Proc Natl Acad Sci U S A 106(45) : 19197-202PubMedID: https://www.ncbi.nlm.nih.gov/pub
Chemogenetics revealed: DREADD occupancy and activation via converted clozapine.Gomez et al (2017) Science 357(6350) : 503-507PubMedID: 28774929
Chemogenetic inhibition of cells in the paramedian midbrain tegmentum increases locomotor activity in rats.Wirtshafter and Stratford (2016) Brain Res 1632: : 98-106PubMedID: 26707405
Limiting habenular hyperactivity ameliorates maternal separation-driven depressive-like symptoms.Tchenio et al(2017) Nat Commun 8(1) : 1135PubMedID: 29074844
What should CNO (water soluble) look like?
CNO (water soluble) is an amorphous, yellow powder
What temperature should I store the solid compound at?
We undertake regular quality control analysis of the solid compound and have found no deterioration in product purity when stored at room temperature.
We recommend that you store solid CNO (water soluble) powder at room temperature (desiccate).
Is the solid powder light sensitive?
No - we have found no evidence for Hello Bio CNO (water soluble) to be sensitive to light.
Is the solid powder air sensitive?
No - we have found no evidence for Hello Bio CNO (water soluble) to be sensitive to air.
How do I weigh the compound to make my stock solution?
You should weigh out the quantity of product that you require for your experiment as the amount of product in our vials isn’t weighed out accurately enough for direct addition of solution.
What should I do if I find precipitate in my stock solution?
Gently heat your solution in a water bath to ~40°C and the compound should readily re-dissolve. Always take care to ensure that the compound is completely dissolved before use.
What concentration should my stock solution be?
This depends on your experiment and the working concentration you require.
What should my stock solution look like?
When dissolved in water, saline, PBS or DMSO your solution of CNO (water soluble) should be a clear, yellow to orange color (depending on the concentration)
Is there a recommended way to solubilize CNO (water soluble)?
Whilst Hello Bio CNO (water soluble) is soluble in water, saline, PBS and DMSO, various groups have different approaches to solubilizing CNO. For example, DMSO is commonly used to dissolve CNO before addition to saline for injection.
Can I store my stock solution of Clozapine N- oxide (CNO (water soluble))?
We recommend preparing and using your solutions on the same day. If this isn’t possible and you need to prepare stock solutions beforehand, aliquot out the solution into tightly sealed vials for storage. Storage of solutions should be at room temperature. We recommend that these will be useable for up to one month. Always check that your product is completely dissolved before use.
How long does Clozapine N-oxide (CNO water soluble) stay stable in solution?
We performed stability studies on 100 mM solutions of Clozapine N-oxide dissolved in water, which were kept at RT and ambient lighting for 4 weeks. No special precautions to exclude air were taken.
No deterioration in product purity (>99.6%) occurred. CNO (water soluble) is stable in solution at room temperature for at least 4 weeks.
Is my stock solution light sensitive?
No - we have found no evidence that Hello Bio CNO (water soluble) is light sensitive.
Is my stock solution air sensitive?
No - we have found no evidence that Hello Bio CNO (water soluble) is air sensitive.
- Working better! Since my last review, we have continued using CNO for conditioned place preference, and results are looking better as we continue to figure out parameters.
- We injected this into rats and saw mild effects. Appeared to work!
- The clozapine N-oxide dissolves perfectly in saline, even at a high dose!