In this interview, industry expert Jesse Bischof explains how inert coating technologies reduce PFAS adsorption and contamination, helping laboratories achieve more reliable, accurate results across sampling, preparation, and analysis in chromatography workflows.
To start, can you please introduce yourself and your role at SilcoTek?
My name is Jesse Bischof, and I’m a Senior Scientist at SilcoTek Corporation. I work on developing and applying our inert coating technologies, particularly for analytical chemistry applications. In this interview, I'm excited to share the highlights from our Pittcon 2025 presentation in Boston, which focused on material selection for PFAS separations. If you didn’t catch us at the event, this is a great way to explore our research and insights.
Can you give us an overview of why PFAS molecules are such a major focus in analytical and environmental testing today?
PFAS molecules are attracting attention because they are everywhere. They’re found in stain-resistant clothing, firefighting foams, non-stick cookware, pesticides, and packaging. Unfortunately, they don’t degrade readily in the environment and tend to bioaccumulate, which means they are present in water supplies, ecosystems, and even human tissue. That’s why they’re sometimes referred to as “forever chemicals.”
Aside from their persistence, there’s increasing concern about the health risks they pose, including links to cancer, reproductive harm, immune system disruption, and more. This has triggered a surge in regulations, particularly in the U.S. states such as California, but similar restrictions are emerging globally, including in the EU and Canada. As more compounds are added to regulatory lists, labs need better, more reliable ways to detect and quantify PFAS accurately.
What methods are commonly used to detect PFAS, and what are their limitations?
To analyze PFAS compounds, labs often use gas chromatography (GC) or liquid chromatography (LC) systems. GC can only handle volatile PFAS compounds, but most PFAS are non-volatile. That’s why liquid chromatography, especially combined with mass spectrometry (LC-MS), is more commonly used – it allows analysts to capture a much wider range of these compounds, even the non-volatile ones.
Regardless of the method, the workflow has critical steps: sample collection, preparation, and analysis. Each of those introduces risks—either through contamination or sample loss. That’s why material selection at each point is critical to achieving accurate results.
What are the risks in the PFAS sample analysis workflow?
At every step—collection, preparation, and analysis—there is a risk of either contaminating the sample or losing part of the PFAS you are trying to detect. You will get inflated readings if the sample picks up PFAS from the container or system materials. On the other hand, if PFAS molecules in the sample stick to surfaces along the way, you might miss them entirely, leading to a false negative.
This makes inert surfaces essential in preventing PFAS from being added or removed during analysis. Any material that touches the sample has to be carefully considered to minimize these risks.
What kinds of materials are typically used in PFAS workflows, and what are the main difficulties with each?
Each material has its own pros and cons. Plastics, for example, are flexible and relatively inert, depending on the type. However, many are made from fluorinated polymers. Therefore, ironically, they may introduce the very compounds you are trying to detect, leading to you measuring contamination that wasn’t even in the original sample. Also, plastics cannot handle high temperatures.
Glass is another option. It is inert to a degree but fragile, and some PFAS molecules have been shown to stick to glass surfaces.
Then there is stainless steel, which is standard in most GC and LC systems—it is strong and widely available, but the downside is poor inertness. PFAS molecules can adsorb onto the metal surface, leading to significant sample loss. This is where SilcoTek comes in. We coat stainless steel to retain its strength while dramatically improving its inertness.
What makes SilcoTek coatings particularly useful in PFAS separations?
Our coatings are designed to make stainless steel surfaces inert without compromising their strength or usability.
We offer two key coatings for this:
- SilcoNert® 2000: an amorphous silicon coating commonly used in GC systems. It prevents PFAS and other reactive molecules from sticking to internal surfaces.
- Dursan®: a glass-like coating that is more suitable for LC applications due to its high pH resistance. It can withstand highly alkaline solutions (up to pH 14) without degradation.
These coatings are designed to eliminate interactions between the analyte and the metal surface. They ensure your sample does not stick, degrade, or become contaminated during analysis.
Where in the PFAS testing workflow are these coatings most critical?
Pretty much every stage can benefit from using coated components. During collection, you might use coated containers or sample transfer lines to avoid picking up PFAS from the container itself. In preparation, filters and valves are areas where molecules might stick or degrade. In the analysis phase, coated tubing and flow paths ensure that PFAS molecules make it to the detector without loss.
If any part of your system leaks PFAS or captures them before detection, you risk false positives or negatives. That can result in failed audits, regulatory fines, or flawed research. So it’s about ensuring confidence in your results from start to finish.
Are these coatings already widely adopted in commercial instruments?
We’re very well established in the GC world. SilcoNert-coated components are common, and many OEMs incorporate our coatings directly. In fact, if you ever open a GC instrument and see a stainless steel part with a rainbow sheen, it’s probably one of ours.
For LC applications, we are earlier in the adoption cycle. Dursan is not yet as widespread, but we are actively working with instrument manufacturers to expand its availability and integrate it into more LC-compatible components.
One thing to remember is that while these coatings add cost compared to uncoated parts, the improved data integrity and reduced risk of contamination make them a smart investment—especially when you're working with trace-level PFAS where adsorption or contamination can completely skew your data.
What are the next steps for improving PFAS analysis through materials innovation?
As regulations tighten and detection limits lower, the industry will need better solutions across the entire testing chain. Our goal is to continue developing coatings that extend inertness into higher pH ranges, more LC-compatible components, and potentially even new materials that combine the mechanical strength of metal with even better inertness.
We are also working to make our coatings more accessible to a broader market, partnering with more instrument makers and offering coating services for custom lab hardware. Ultimately, we want to help labs get the most accurate results possible with the least risk of sample interference.
About Jesse Bischof 
Jesse Bischof is a Senior R&D Specialist at SilcoTek Corporation, specializing in advanced coatings for medical and analytical applications. With a Ph.D. in Chemistry from Penn State, he focuses on bio-inert and anti-fog coatings, metal ion barriers for HPLC, and developing robust metal oxide coatings to enhance material performance.
His work bridges the gap between research and real-world solutions, helping customers achieve better performance and accuracy in challenging analytical environments.
Disclaimer: The views expressed here are those of the interviewee and do not necessarily represent the views of AZoM.com Limited (T/A) AZoNetwork, the owner and operator of this website. This disclaimer forms part of the Terms and Conditions of use of this website.