Kareem Ahmed, PhD, and Michael Kinzel, PhD, Assistant Professors of Mechanical and Aerospace Engineering at the University of Central Florida talk about their research on developing a cough drop that could slow the spread of COVID-19 and reduce the space needed between people.
Michael Kinzel, PhD
With your background in Aerospace, how does that correlate to you working on this project?
Michael Kinzel: In Aerospace I worked a lot in multiphase flows involving cavitation, sprays, droplet interactions with aircraft. This background led to a secondary look at understanding the fluid mechanics associated around coughs, squeezes, and speech, and that is where my expertise comes into play.
How did the idea of the lozenge come about?
Michael Kinzel: The idea of the lozenge originally started as something that alters fluid properties to manipulate sprays. My wife was in an argument on Facebook with one of our neighbors about people who were walking and running the other way from people and they were not getting too close. I was on a run and thinking about this process and concluded, why don’t we start thinking about eliminating aerosols? You can do this by changing fluid properties such as surface tension and viscosity, and that led to, how would you implement this? Things like gums, lozenges and so forth. Then we moved into studying various ingredients for a lozenge that could change your saliva, so that it does not lead to aerosols. I think what we are getting is even further than what we anticipated. The binder or the saliva reduction agent, seems to be outperforming with respect to changing the fluid viscosity and surface tension.
Is there an active ingredient that you found more effective?
Michael Kinzel: Corn starch was our original ingredient that we evaluated, but we found thickeners that are food-grade that outperformed it. It was just the original one that we evaluated. The reduction agents are based on very selective herbs that actively work to reduce the amount of saliva in your mouth. Again, these are all food-grade herbs.
You mentioned that there are other ingredient sources besides corn starch. Can you list some of them?
Michael Kinzel: The ones we are using now are xanthan gum and agar which are more like gelatin and they are off-the-shelf type ingredients. If you just put them in your mouth, it is not extremely comfortable. That is why I think the lozenge laden with these different ingredients is the way to go because we can formulate the lozenge, so it is comfortable for you. Now when I say that you are not comfortable, it is not like you have this sticky stuff in your mouth, but it is slightly uncomfortable. It is not like loading your mouth with the ingredients, it is only less than a gram.
How do you guys go about testing this?
Michael Kinzel: We are looking at both experimental and numerical simulations. The experiments are the ground truth and they are our best representation of what is going to happen. What we are doing is putting the ingredients in our mouth and inducing a sneeze as soon as possible, using high-speed visualization to record what is going on. Then we process those high-speed recordings to understand how we reduce saliva with respect to a baseline type sneeze, so a sneeze without any mask or ingredient in the mouth. What we are trying to do with the numerical modeling is understand what the underlying mechanisms are. We were talking about primary and secondary breakup, so we are understanding how the droplets form in your mouth from the sneeze event coming much like driving air through little film layers in your mouth and how the little droplets are ejected from your mouth and how they break up. That is the secondary breakup process. We are using numerical models to better understand those physical mechanisms.
What can this mean for people when it comes to social distancing?
Michael Kinzel: We hope to formulate this so it could work with a mask or potentially not even a mask but still use the lozenge and at the same time decrease the distance that you have to maintain. So instead of maintaining 6 feet, maybe you can maintain three or two feet. In terms of hugs, maybe we need to do a hug test. That would be a fun one to evaluate.
When it comes to parents nowadays, they are afraid to send their kids back to school in the Fall as it is extremely hard to keep students six feet away from each other.
Michael Kinzel: It is hard to keep kids six feet away from each other and to keep a mask on them for long durations. In theory, a school is the one place where this would really have a lot of potential. But to have them continuously wear a mask, that is more difficult. When kids play, breathe, speak, or cough they are going to get a buildup of droplets in the air. If we can reduce the number of droplets that are sustained in the air, I think it would be an effective measure. We have a lot more testing to do to show that kind of ability, but all our preliminary data indicate that can be achieved.
What are the next steps?
Michael Kinzel: The next two steps are doing clinical studies looking at variations in participants and honing down on our measurements and comparing a model to a baseline sneeze. I think what we are going to do is use a six feet baseline sneeze as our metric. That is the only guideline that we really have based on the CDC guidelines. What we are going to do is evaluate the amount of saliva generated at six feet in distance with respect to somebody’s mouth and figure out how we can reduce that and where does that same level of saliva content come when we use these novel type methods. If we have the same type of saliva content at two and six feet, we have a metric of how effective it is.
How long do you think it will be until this will get in the hands of people?
Michael Kinzel: That is one of our biggest challenges. We are mechanical and aerospace engineers. We are not food scientists and we do not have the infrastructure to really produce these lozenges in massive quantities. One of the things we are doing is looking for licensees – pharmaceutical companies, lozenge manufacturers and other people who might be interested in bringing this technology or implementing this technology on a wide scale. In the meantime, we are exploring options on our own. If we explore it on our own, we have a lot of issues with formulating something that tastes good, building all the logistics, getting all the supplies, manufacturing them, and who do we sell it to. It is not an easy thing to do unless we already have that infrastructure in place.
Are you hoping within the next couple months or a year?
Michael Kinzel: If it were not urgent, we would focus on driving our own company, but we feel like we have a product for the long term. However, considering we have a pandemic, we think that the best option is to focus more on companies that are able to implement it quickly and are already making something then all we have to do is transition it to market, and they have all the infrastructure for manufacturing it in place. If we can get a company to license our technology, we think it might be as early as four to six months. If we do it ourselves, it might be year to a year and a half. It all depends on how fast we can ramp things up. I think one of the good things is our active ingredients are all food grade, so we do not have to get formal FDA approval to start implementing this. With that in mind, I think we have a product that should be implementable as soon as we can get all the infrastructure into place to make it happen.
Is there anything that I did not ask that you feel people should know?
Michael Kinzel: I think it is important to realize that using masks is still important. We are not suggesting we want to get rid of masks by putting ingredients like corn starch in your mouth. Our key focus is how do we make masks more effective? How do we have people interact with each other and get things back to normalcy? If we can do that, I think we would be happy with our research and making a difference to society.
Kareem Ahmed, PhD
Talk a little about how this idea came about.
Kareem Ahmed: The inception of the idea came when we were looking at biofuels for propulsion and aerospace-related applications. Biofuels is altering the viscosity, density, and surface tension of fuel itself. The principle is the same where you are looking at aerosols and droplets that are formed because of human respiratory function. The idea was if you could alter the viscosity, density and surface tension or make it thicker and heavier you could change the droplets that form when you sneeze, cough or speak, and they will fall down rather than transmit to the next person.
How can using this concept change someone’s saliva?
Kareem Ahmed: Essentially the cough drop would be infused with your saliva. Most of saliva is water-based so it blends in with water. By doing that, you are changing the property of the saliva, making it thicker and stickier. As a result, whenever your breathing, coughing, or speaking it will make the droplets bigger and they will fall on the ground.
Is there a specific ingredient or can this apply to all?
Kareem Ahmed: We actually found out that if you use a regular lozenge for coughs that they’re not effective because they have sugar, and sugar tends to trigger your tissue to produce more saliva so that doesn’t help the droplets because then you’re producing larger droplets. We only discovered this as we were doing the research. We are looking for specific properties such as organic-based off-the-shelf properties that would tend to thicken it, and beta blockers. For example, corn starch, peanut flour or agar are good thickeners that will essentially dissolve with saliva and make it thicker. But we also looked at beta blockers to reduce the saliva production.
What implications can this have for the fight against COVID-19?
Kareem Ahmed: Essentially, we wear face masks to reduce the transmissibility and we show that even though face masks are effective at reducing the ejection of particles they still allow some droplets to pass through. This would help to effectively make face masks more effective in reducing the droplets that do come out. The other aspect is that you can use it and get to the state where you don’t produce any droplets, even from a strong respiratory function like a sneeze because a sneeze is where you produce a significant amount of droplets. So, we show that it is more effective than a mask.
What are the next steps for this?
Kareem Ahmed: We filed a provisional patent on the idea. We are submitting papers which will get peer reviewed on the concept. But we are also talking to some sponsors to license the provisional patent so they can take it and make a product out of it.
How long until you can get in people’s hands?
Kareem Ahmed: We are already formulating a lozenge in our labs for testing. Because we are using off-the-shelf ingredients, it is just the mixture that we are establishing. I think the challenge is to scale up the mass production, and that is where we have the provisional patent. We are trying to work with companies that will take the provisional patent and mass produce it for the public.
Would you like to see it by the end of this year?
Kareem Ahmed: Within a couple months to three months we are hoping to have it available so that folks can start using it. Basically, when you go into a store, they will hand you this lozenge that you have to chew on as you are going in or when you’re getting on a flight to reduce transmissibility. The goal is to have it as quickly as possible.
What can this lozenge do in relation to social distancing?
Kareem Ahmed: So, the guideline that the CDC provides is six feet with a mask. The idea is if you were to have this lozenge with a mask, you can reduce the distancing to a couple of feet. So that would bring people closer in terms of the social distancing while mitigating any transmission of the virus.
Do you have a certain amount of feet that you think will be most effective?
Kareem Ahmed: I would say with the lozenge and the face mask, it could bring the distance down to two feet which is about a third of the CDC guideline distance.
Anything I did not ask that you feel people should know?
Kareem Ahmed: Some are feeling discomfort with wearing the face mask and this could be another alternative, but it is harder to enforce. This could be an easier alternative that could be used along with the face mask where you can just take a lozenge and mitigate it, compared to not wearing a mask or even having any control of transmissibility.
How effective do you believe the lozenge could be?
Kareem Ahmed: We are working with companies to take the provisional patent and convert the idea into three different forms. One is a lozenge cough drop that can last 20 to 40 minutes during a grocery store visit or a flight. There’s also breath mint strips which are buccal films, where the ingredients are imposed on a buccal film, and that will give you a shorter visit to a store for 20 to 30 minutes, and then there is a medicinal-based where you can have a longer duration where you would not produce these droplets. It depends on the form and you would have different forms that you could choose from. So, the different forms of it is really what will help with the time.
How are you testing it and how does it work?
Kareem Ahmed: We use multiple forms for measuring data. We are using real human respiratory functions – sneezes, speaking, coughing, yelling – because these are the kind of forms that will emit droplets. We use high-speed cameras which to measure the droplet formation and emission of the respiratory function. But we also have a particle analyzer that takes the particles and counts how many you are producing and what sizes you are producing these particles at. So that is what we are doing experimentally to characterize the emission that comes out. You can clearly see where the natural saliva produces an emission that sprays strong versus when you have a face mask or when you induce this thickener, it will tend to reduce the droplets. But when you combine it with a beta blocker, you almost have no droplets.
Right now, you are only testing sneezing but are you testing coughing or speaking?
Kareem Ahmed: We’ve been working on coughing, loud speaking, and tones because it is a different form. Sneezing is the strongest way where we can show the effect clearly. Coughing and speaking tends to produce less droplets, so it is harder to characterize and to see in a public form, but the data shows it, so we are looking at coughing and speaking as well.
Interview conducted by Ivanhoe Broadcast News.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
If you would like more information, please contact:
Robert Wells
University of Central Florida
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