Program ID: Innovation Anthology #446
Program Date: 01/10/2012
Program Category: Agriculture, Biotechnology, Health and Medicine, Life sciences, Women in Science
Innovotech 1: New Silver Technology Kills Biofilms
PROGRAM #446 INTERVIEW WITH DR. PATRICIA NADWORNY
MP3: 12.2 MB
Time: 13:23 Minutes
Dr. Patricia Nadworny is a research scientist at Innovotech in Edmonton. Her position is funded through the Industry Associate program of Alberta Innovates Technology Futures.
Dr. Patricia Nadworny
CC: PATRICIA, YOU’VE BEEN WORKING AT INNOVOTECH FOR A COUPLE OF YEARS AND ONE OF THE THINGS THAT YOU’RE WORKING ON IS BIOFILMS. COULD YOU TELL ME FIRST OF ALL, WHAT ARE BIOFILMS?
PN: Sure. Bacteria, essentially, can live in two different states. One is as planktonic, where they live as individual bacteria floating freely. And then the other form is as a biofilm which is essentially a community of bacteria. And typically they live on surfaces and they form a protective layer.
The difference between biofilms and planktonic bacteria is that biofilms are a lot more resistant to treatment. They’re much more difficult to kill because the bacteria are working together and they have this protective layer.
So they can be a thousand times more difficult to kill than planktonic bacteria. And they are the most common state for the bacteria to be in.
Unfortunately, the research to date and most of the products that have been developed so far are based on knowledge of the planktonic bacteria. And so a lot of what’s available now doesn’t work on biofilms.
CC: SO IS THE CONCERN THAT THESE BACTERIA AND THESE BIOFILMS CAUSE DISEASE?
PN: Yes, that’s right. Biofilms are responsible for 80 percent of infections. And so, they will show up for example in chronic wounds, in medical devices, associated infections, a lot of hospital acquired infections. They are present in the lung infections of cystic fibrosis patients. So they are a serious problem in infections.
CC: WHEN YOU SAY THEY’RE A FILM, DOES THAT MEAN THEY’RE KIND OF SLIMY?
PN: Yes, that’s right. The biofilms that you’ll see most common examples would be the slime on rocks in rivers or plaque forming on teeth.
CC: WHAT ARE WE DOING TO ATTACK THESE BIOFILMS AND GET RID OF THE DISEASE THAT THEY CAUSE?
PN: The problem is that a lot of industry hasn’t been focusing on biofilms. But Innovotech is focusing on treatment specifically for biofilms.
We have developed testing systems where we can grow biofilms in a consistent high throughput way. Then we can screen for a number of chemicals quickly to determine which ones will actually be effective against biofilms.
CC: I UNDERSTAND THAT SILVER HAS AN AFFECT ON BIOFILMS. THAT IT CAN KILL IT. AND THAT’S ACTUALLY SOMETHING THAT YOU’RE WORKING ON. HOW IS IT THAT SILVER ACTS AS AN AGENT TO KILL OFF THESE BIOFILMS?
PN: That’s a good question. I should start by clarifying that not all silver is equal. So some forms of silver have no effect on biofilms or actually on any bacteria. And so it all depends on how the silver is used.
So, for example, if you took silver that’s in say jewelry, which is metallic silver and has no charge. It will not have any impact on bacteria at all.
So then if you charge the silver, so for example, silver nitrate has a plus one charge, it will have an effect on bacteria, but still a lot of the silver products that are available in the medical device arena right now have a lot of problems in terms of their ability to kill bacteria because either they can be very low solubility, meaning the silver is not released into the environment and so it won’t actually interact with the bacteria to kill them.
The other problem is that silver can often be inactivated by bodily fluids and so on, and so again, it’s not available to kill the bacteria. So you need to have a form of silver that is not easily inactivated and is more soluble to really have a good impact.
So the products we’re working on we’re really excited about because it has a higher charge and so it’s more reactive with bacteria but at the same time we’ve developed formulations that actually are not readily inactivated by bodily fluids.
CC: WELL LET’S LOOK AT THE AREAS OF RESEARCH THAT YOU’VE BEEN INVOLVED IN. I GATHER THAT IT GOES ACROSS QUITE A RANGE. WHAT IS IT THAT YOU ARE ACTUALLY WORKING ON?
PN: I’ve mostly been working on two main projects with two different families of silver compounds. One of them is geared towards an agricultural application.
So the problem that we’re trying to address is that a lot of agricultural crops right now are being treated either with streptomycin which is being banned in a lot of places or the bacteria are actually developing resistance to the streptomycin.
CC: SO IS THAT LIKE AN ANTIBIOTIC?
PN: Yeah, that’s right. That’s an antibiotic. And a lot of places are saying you can’t use that anymore.
And so that’s one problem. Another problem is, some diseases in the plants there just is no treatment for them right now. So, in order to prevent the infections from spreading, they actually end up having to destroy the crop. So that’s very wasteful, coming at a time when we have less and less agricultural land use and more people to feed.
And so it’s really important to develop treatments for some of these diseases or prevent the diseases from occurring so that you do not have to destroy your crops.
So the one compound that we’ve developed it has a high valency silver compound. It’s showing good promise as a seed treatment but also as a foliar spray and what I’ve been working on is developing a package to have it registered with the Environmental Protection Agency for those applications.
CC: SO WHEN YOU SAY A PACKAGE, WHAT DO YOU MEAN?
PN: So I’m working on a chemistry package. Just basically all of the information that they need to know to understand how the compound behaves in different environments so they can be confident that it’s safe to use.
CC: CERTAINLY IF IT’S TOXIC TO THE PATHOGENS THAT YOU WANT TO GET RID OF OR TO PROTECT THE SEEDS, DOES IT CAUSE ANY PROBLEMS FOR SAY HUMAN CONSUMPTION?
PN: For the plants, obviously the first thing you need to worry about is phytotoxicity--whether it will harm the plants. And we haven’t seen any issues with that.
The concentrations that we’re treating at are very low as well and so we test for silver in the product, say the beans at the end or whatever. And they’re basically undetectable. It’s not higher than it would be in a control material. So humans will not be consuming the product.
CC: HOW WOULD YOU ACTUALLY USE IT?
PN: Basically we would coat it onto the seeds and so that provides a preventative method, because you’re actually killing the bacteria on the seed before the plant starts to grow.
For some other applications, you can also spray it onto the leaves.
CC: NOW BEYOND THE AGRICULTURAL USES, ARE THERE USES FOR HUMANS?
PN: Yeah, we’re actually, we have a different family of silver compounds that we’re focusing on the medical device applications. We are working on coating different types of metals such as titanium or stainless steel that you would use either in implants or various operating room equipment, that kind of thing.
We’re also looking at incorporating the silver into polymers or coating the silver onto polymers. And that could be used potentially in the catheter industry or wound dressings.
CC: SO IS THAT A PROBLEM WHEN PEOPLE ARE EITHER BEING OPERATED ON, SAY GETTING HIP REPLACEMENTS OR SOMETHING LIKE THAT OR GETTING TREATMENT FOR URINARY PROBLEMS, THAT THEY CAN GET THE INFECTION THAT WAY?
PN: Yeah that’s right. A lot of hospital acquired infections are biofilm associated and any time that you are putting a device into a person or you have a needle or a catheter that’s basically penetrating the skin or whatever; you have a likelihood of developing infection. And urinary infections are extremely common for people who have extended stays in the hospital.
CC: WHAT IS THE CURRENT PRACTICE?
PN: Right now there are a number of different practices that they have in place whether it’s just trying to clean the site well beforehand. There are some different coatings that have been applied to some of these devices. But Innovotech does a lot of contract research for other companies and so they will send us the devices that they are developing and we can test them and let the companies know whether the devices are actually effective against biofilms or not. And we’ve seen quite a gap in this market still.
CC: WHAT ARE THE CHALLENGES FOR YOU IN DEVELOPING THIS SORT OF TECHNOLOGY? ARE THERE THINGS, OBSTACLES THAT YOU HAVE TO OVERCOME STILL?
PN: Certainly there are always challenges when you’re trying to develop a new medical device.
For silver in general, some of the challenges that we’ve had to overcome in terms of developing a product that would be different, we did have to make sure that we had a silver product that was more soluble that was released more readily and we do think that we have that now.
Another issue of course is the inactivation and so we had to screen various products to see how they behaved in different bodily fluids.
Coating methods is always a challenge as well. That’s something we’re still working on but we do have good promise, especially in the area of metals coating. We’ve had some good successes there.
As you mentioned earlier, the cost of silver is always an issue. So you need to find manufacturing methods that are inexpensive and simple to offset some of the cost of the silver itself. Or in the case of one of our products, we’ve found a silver compound that has a very low weight of silver but is still very active and that’s a way of getting around the cost of the silver itself.
CC: ARE ANY OF THESE ON THE MARKET ALREADY OR ARE YOU STILL IN THE PROCESS OF COMMERCIALIZATION?
PN: We’re still in the process of commercialization of our silver products. We do have other products on the market. As I mentioned earlier, we have the high throughput methods of growing the biofilm. And so we have the MBEC Assay™, which is available and it’s actually an international ASTM standard now.
We also have some other devices that are available. We have some susceptibility testing kits. The silver products are still in the pipeline.
CC: SO ONCE THIS DOES GET TO MARKET AND ITS BEING USED IN HOSPITALS, IN SURGERY, THAT SORT OF THING OR IT’S BEING USED IN FARMER’S FIELDS, WHAT DO YOU SEE AS BEING THE MARKET POTENTIAL FOR THIS?
PN: The medical device market is a $5 billion dollar market. Obviously depending on which applications we focus on it will be a subset of that market. The agricultural crop protection market is a $13 billion dollar market. And at this stage we do have a large commercial partner, international, who is planning to include our product in their treatment regime.
CC: YOU HAD SAID EARLIER THAT BIOFILMS ARE RESPONSIBLE FOR ABOUT 80 PERCENT OF THE INFECTIONS THAT WE SEE. ONCE YOUR PRODUCTS GET OUT ON THE MARKET, WHAT DO YOU THINK THE IMPACT IS GOING TO BE?
PN: Right now, there are 17 million people in the US who suffer from biofilm infections every year with a cost of $94 billion dollars. And of those people, 550,000 die every year. And so, we think that products like the ones we’re developing will have a big impact in reducing the number of deaths due to biofilm infections and the cost associated with that in terms of hospital hours, various products that aren’t working as well, and of course, our main goal is to improve the health of people suffering from biofilm infections and prevention of biofilm infections.
CC: YOU’VE BEEN WORKING ON THIS PROJECT THE LAST COUPLE OF YEARS AS AN INDUSTRY ASSOCIATE FUNDED THROUGH ALBERTA INNOVATES TECHNOLOGY FUTURES. HOW HAS THAT HELPED YOU AND HOW HAS THAT HELPED THE COMPANY?
PN: This has been a really good experience for me. I started with this company basically right out of my PhD. And it’s been great to get some industrial experience. I’ve had the opportunity to learn about biofilms a lot more. My PhD was on silver, but I’ve been able to expand my knowledge in that area as well, which is pretty exciting to be able to do something that was so related to what I’d been doing before.
I’ve gotten the chance to learn a lot about manufacturing and working under GLP and ISO 13485. I’ve gotten to learn about intellectual property and regulatory processes. So it’s been a really good experience for me especially with this particular company.
It’s a smaller company so you get to try lots of things and it’s an area that I’m really excited about.
So, that’s been a really good opportunity as well because there’s that research allowance that comes with the grant, I’ve been able to attend some conferences and workshops and courses that have been really helpful for me as well.
For the company, I think, it’s given them the resources to move some these silver related projects forward. And you know, just get some more products moving through the pipeline towards market.
CC: THANK YOU VERY MUCH PATRICIA.
PN: Thank you.