The video recording of our recent webinar, "Analysis, Optimization and Production of Translucent Nanoemulsions", presented by Industrial Sonomechanics' R&D Scientist, Mr. Shlomo Leibtag, and Micromeritics' Global Technical Training and Support Manager, Mr. Jack G. Saad, is now ready. The webinar had over 200 registered participants and generated close to 100 questions. Some of these questions were addressed by Shlomo and Jack during the event. The answers to the rest are provided below. If you have any additional questions, please do not hesitate to contact us or leave a comment below.
1. How much carrier oil to cannabis oil do you suggest for a good, stable nanoemulsion?
This question was answered during the webinar. Please see time stamp 0:16:49 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
2. What do we need to know about emulsions vs. powders?
Emulsions are suspensions of two immiscible liquids, one dispersed as droplets (dispersed phase) in the other (continuous phase, generally water). There are several techniques (e.g., binder addition followed by spray drying) that can be utilized to remove the water and convert the emulsion into a powder. If prepared properly, these powders can then be resuspended (reconstituted) in water to reform the original emulsion.
3. Is there a low-cost drying method for making solid nanoemulsions?
Typically, water-soluble nanoemulsion powders are made by spray drying liquid nanoemulsions after adding a suitable binding agent.
4. What is the relationship between electrostatic repulsion (charge separation as measured by zetas potential) and steric repulsion? Specifically, does the bonding of polymeric surfactants required for steric repulsion affect zeta potential? Dr. Tadros, in his book Nanodispersions, makes the point that steric repulsion is more robust than electrostaticv repulsion for emulsion stability. If I am introducing polymeric surfactants in a formulation, should I ignore changes in zeta potential?
This question was answered by Mr. Jack Saad from Micromeritics during the webinar. Please see time stamp 0:55:26 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
5. I understand that the NanoStabilizer® is recommended to be used at the maximum temperature of 60 C, but if we were to want to add a nanoemulsion to a candy making progress, where the cooking temperature may be as high as 140 C and the batch must be fully homogenous, what would be your recommendation to add such an emulsion to the product without dramatic increase in particle size?
Oil-in-water (o/w) nanoemulsions, in general, should not be manufactured, stored or further processed at temperatures above about 80 C as water may evaporate and/or surfactant layers on droplet surfaces may become disrupted at higher temperatures. Nanoemulsion-containing products with high-temperature stability can, however, be feasible and must be considered on a case-by-case basis.6. What is the maximum possible concentration translucent nanoemulsion with perfect formulation and technique? Is there a physical limit?
We recommend not exceeding 50 mg/ml (5%).
7.What is the average lifespan of a Barbell Horn®?
If you are preparing a nanoemulsion and using NanoStabilizer®, a Barbell Horn® normally lasts around 200 hours. However, this is only a rough estimate. The process should be optimized in order to maximize the life of the Barbell Horn®. Horn erosion can be significantly reduced by making sure not to exceed the optimal amplitude for the process. You should try amplitudes between 60% and 100% of the maximum value and compare the results. If, for example, you see similar results at 75% and 100%, you should stay at the lower setting. It is also important to limit the processing time to what is needed to reach the desired droplet size. At some point in the process, the droplet size will plateau as a function of time, and you will no longer be improving your product. Horn erosion would, however, still be taking place, so this processing period should be eliminated.
8. Do you have comparative analysis between NanoStabilizer® vs. Polysorbate 80/lecithin system?
We do not have such data, unfortunately.
9. Have you cracked the extraction by using water as a solvent yet?
The process of extraction with water used as a solvent is still in the R&D phase. When we have updates, we will post them on our blog.
10. For water-in-diesel nanoemulsion, is it possible to have a translucent emulsion with 30% water?
We have successfully gone up to 20%. It may be possible to get to 30% but R&D will likely be required.
11. Is it possible to get a test product? For example, may I arrange a visit to your Miami facility or send CBD oil to obtain a test product?
Yes, we offer testing via our consulting services. You are welcome to either ship your CBD extract to us or bring it with you on the consulting day. If this is of interest, please fill out our consulting questionnaire:
https://info.sonomechanics.com/consulting-service-questionnaire
12. What would be a good natural substitute for Poly 80 to avoid the acrid taste?
Quillaja Saponin, Lecithin and Gum Arabic are good natural surfactants. The bitter taste, however, frequently comes from the extract itself. Please see the following post for more details: http://blog.sonomechanics.com/blog/managing-the-bitter-taste-of-cannabis-infused-beverages
13. Do you have any comparative analyses between CO2, ethanol and ultrasonic extractions?
We do not have such data, unfortunately. This article may have some helpful information, however:
http://blog.sonomechanics.com/blog/cannabis-concentrates-medical-significance-and-extraction-methods
14. I have tried NanoStabilizer® without using any equipment to reduce the particle size, just to see the preliminary mixture. It has a bitter flavour, does it disappear when the particle size is reduced?
NanoStabilizer® is practically tasteless. The bitter flavor you are referring to is likely due to the extract you are using. Also, as a reminder, nanoemulsions are not designed to be tasted directly. They should be infused into a beverage or another water-based product.
15. How does your ultrasound mixer compare to high-shear mixers?
This question was answered during the webinar. Please see time stamp 0:50:23 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
16. If you were to run a 2:1 nano-emulsifier:product/oil and decided you wanted it to be more transparent, can you re-run the material through the ultrasonic processor with more nano-emulsifier to increase the ratio?
This question was answered during the webinar. Please see time stamp 0:59:33 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
17. For transparent water-in-fuel emulsions with 10% water, what are the approximate sizes of droplets? What instruments are good to be used to characterize the droplet sizes for such clear emulsions?
That would normally depend on the formulation used. The appropriate droplet size measurement techniques are dynamic light scattering and laser diffraction. Please contact Mr. Jack Saad from Micromeritics in order to receive information on instruments for measuring particle sizes in nanoemulsions: https://www.micromeritics.com/Contact-Us.aspx
18. Has your company tested samples to see if the particle sizes have changed within a year?
Yes, the droplet sizes remain within 10% of their original value over the course of a year.
19. Can you use a full-spectrum oil (80% purity) instead of isolate?
Yes, you can. You can use full-spectrum oils, isolates, distillates, essential oils, vitamins, and most other oils (or combinations thereof).
20. Do you know of any good natural surfactants?
Yes, we offer such formulations, please contact us for further information at: https://info.sonomechanics.com/contact-us-general-inquiry
21.Why do most companies us Polysorbate 80?
We cannot speculate on this, unfortunately.
22. Can you recommend a good entry level bench-top DLS instrument?
Please contact Mr. Jack Saad from Micromeritics in order to receive information on instruments for measuring particle sizes in nanoemulsions: https://www.micromeritics.com/Contact-Us.aspx
23. Does the dilution factor have impact on particle size, how you can be sure you find the best dilution factor to determine the size of droplets by DLS?
This question was answered during the webinar. Please see time stamp 0:52:17 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
24. Particle size is very helpful to know however I'm wondering how we can confirm concentration in mg/ml post filtration. I assume large particles get held in the filter and can alter the final concentration (as compared to calculating from inputs).
This question was answered during the webinar. Please see time stamp 0:57:57 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
For additional information on filtration, please see the following article:
http://blog.sonomechanics.com/blog/should-i-filter-my-water-soluble-cannabis-nanoemulsion
25. How can we confirm that can linings are no longer holding any particles (that the particles are not sticking to the beverage can linings)? Similar to above, testing the final concentration.
Can linings typically have hydrophobic surfaces. This can present a problem for canned beverages containing nanoemulsions because oil droplets in nanoemulsions can adsorb onto the inner can lining surfaces, thereby decreasing the concentration of the oil in the bulk product. If one intends to develop a canned beverage containing a nanoemulsion, it is highly recommended that several different formulations and can linings be tested and oil concentration be measured over time in each case before proceeding with commercial production.
Additionally, there are techniques to inhibit the inner can lining surfaces to prevent oil droplet adsorption, which we can help you test and implement. Please contact us for further information at: https://info.sonomechanics.com/contact-us-general-inquiry
26. Wouldn't a higher ratio of surfactant to mass of dispersed oil be required for these systems to achieve transparency?
Not if the formulation is properly developed. When using NanoStabilizer®, for example, the total amount of oil(s) exceeds the total amount of surfactants, and the resulting nanoemulsion is translucent (transparent upon dilution in water).
27. When using a 90% THC distillate, because of the ratios of surfactant:carrier oil:extract, is there a maximum potency per ml of nanoemulsion?
For a translucent nanoemulsion prepared with NanoStabilizer®, the maximum recommended extract concentration is 50 mg/ml. Therefore, for a 90% THC distillate, the maximum concentration of THC would be 90% of 50 mg/ml = 45 mg/ml. For non-translucent (opaque) nanoemulsions, extract concentrations of about 100 - 150 mg/ml are achievable.
28. How does a finished nanoemulsion (before being dosed in water) stand up to heat?
This question was answered during the webinar. Please see time stamp 0:54:34 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
29. Is it possible to achieve higher-concentration self-emulsifying systems if you combine the system with ultrasonic processing?
Self-emulsifying systems require much higher ( ~ 4 - 5 times) surfactant concentrations than formulations processed with high-intensity ultrasound and are generally difficult to develop beyond the laboratory scale. Additionally, they typically lead to microemulsions rather than nanoemulsions, which have additional disadvantages. Please see the following article for more information on the differences between these two types of formulations:
https://blog.sonomechanics.com/blog/water-soluble-cannabis-oil-microemulsion-liposomes-or-nanoemulsion
30. Water-soluble, nano-emulsified cannabis oils tend to destabilize around the 160 F range or thereabout using sonomechanics stabilizer and similar types of stabilizer compounds. What does the destabilization process entail (physically) and how can it be improved upon for high-heat applications (candies, etc.)?
Oil-in-water (o/w) nanoemulsions, in general, should not be manufactured, stored or further processed at temperatures above ~ 80 C (176 F) as water may evaporate and/or surfactant layers on droplet surfaces may become disrupted at higher temperatures. Nanoemulsion-containing products with high-temperature stability can, however, be made and must be considered on a case-by-case basis.
31. What about pressurized processing chambers?
Attempting to sonicate under pressure will increase the power required to operate and decrease the size of the cavitation zone created by sonication. Both of these aspects will result in decreasing the efficiency of the sonication process.
32. Do you always require a carrier oil?
Carrier oil is a required component of every nanoemulsion formulation. For more information, please see the following article:
33. How does ultrasonic processing compare to ultra high-pressure emulsification?
A significant drawback to utilizing high-pressure homogenizers is the high pressure (commonly >3000 atm) that must be maintained throughout the process, resulting in a high power requirement that imposes significant operating and maintenance costs. The following peer-reviewed publication shows a comparison of the two techniques (see last section): https://www.sciencedirect.com/science/article/pii/S0168365917301128?via%3Dihub
34. Do we always need to choose between solving for transparency and flavour?
Please see the following article:
http://blog.sonomechanics.com/blog/managing-the-bitter-taste-of-cannabis-infused-beverages
35. Does the NanoStabilizer® have any synthetic surfactants? For example, could we make the label claim of "natural ingredients" if we use your product?
This question was answered during the webinar. Please see time stamp 01:01:55 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
For more information on NanoStabilizer® please visit:
http://blog.sonomechanics.com/blog/6-frequently-asked-questions-about-nanostabilizer
http://blog.sonomechanics.com/blog/nanostabilizer-for-producing-water-soluble-cannabis-extracts
36. Is there anything unique with olive oil in your formulation described during the webinar? Will other oils, like MCT, work?
This question was answered during the webinar. Please see time stamp 01:01:00 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
37. What is the difference between your NanoStabilizer® and some other commercial surfactant mixtures?
NanoStabilizer® was specifically developed with the customer in mind, as they take on the challenge of creating a nanoemulsion. NanoStabilizer® is a user-friendly yet robust all-in-one formulation that, when combined with an active ingredient (e.g. CBD, THC, isolate, distillate) and distilled water and processed with our turn-key ultrasonic equipment, creates unique nanoemulsions with extremely small droplet sizes, high degree of translucency, short onset time, and significantly enhanced bioavailability profile. It takes the guesswork out of the process for the customer while also enabling them to make nanoemulsions customized to their requirements. NanoStabilizer® is a trademarked, proprietary all-in-one blend of tasteless, natural source-derived ingredients, which has been proven via comparative studies to be far superior in all aspects to the competition, including commercial surfactants and mixtures thereof.
38. Can you make translucent solution at 50mg/ml of CBD, using distilled CBD?
This question was answered during the webinar. Please see time stamp 0:51:35 of the webinar recording: https://youtu.be/Vn66ts-Dxd0.
39. What is the shelf life or stability of the nanoemulsion.
A correctly prepared translucent nanoemulsion will exhibit permanent kinetic stability against droplet flocculation and coalescence. It can be stored in its concentrated form or diluted to any desired concentration and will still never separate. Cannabinoid degradation may still occur due to UV light exposure or microbial activity, the same way it may occur in any cannabis product. To achieve long-term shelf life, the nanoemulsion must be sterilized by passing it through a 220 nm pore filter and be stored in a dark-glass autoclaved container.
40. How much is your equipment?
For pricing information, please contact us at:
https://info.sonomechanics.com/main-contact-us