As we celebrate this day in our calendar, we reflect on the experience of some of our female colleagues and why they were drawn to careers in science. Here’s what they had to say:

Eirini

I got into science because I love puzzles; the satisfaction when an idea clicks in my mind and then actually works in the lab! Since 2019, I’ve been designing assays and translating complex biochemical experiments into practical lab applications. I’m now an R&D Scientist at FMS, where I help turn diagnostic ideas into real-world products. It’s rewarding seeing my work become part of outputs that could directly impact patient testing and outcomes.

Mala

I’m a R&D Scientist at FlexMedical Solutions (FMS), with over 15 years’ experience in IVD development. I was drawn to science by curiosity and a care for others. Starting as a Product Support Investigator, I learned the importance of understanding real-world needs. Moving into R&D allowed me to turn ideas into products; seeing them reach patients is incredibly rewarding. At FMS, I’ve really valued the collaborative, cross-functional culture that supports growth and innovation. Being a scientist lets me ask questions and discover new things, and I want other girls to see that possibility for themselves.

Victoria

I am Quality Engineering Analyst at FMS with a background in forensic and analytical chemistry. I was drawn to science by curiosity and the opportunity to use problem-solving skills to make a real difference. At FMS, I’ve been able to grow my experience across R&D, Production, and Quality while contributing to the development of medical devices.

Kerry

I am a Senior R&D Scientist and Project Manager at FMS. I have spent four years working across a range of innovative projects. I’ve always loved science because it’s exciting, creative, and full of possibilities. My time at FMS has given me that chance to grow and lead meaningful work, whilst being part of a supportive team.

Sarah

Driven by curiosity and a passion for problem-solving, my journey in science took me from Animal Science into Bioengineering, where I completed a Master’s degree and PhD exploring stem cells as a novel approach to brain cancer treatment. Alongside my research, I set up a society to support women in engineering, while solo travel helped build resilience, independence, and a sense of adventure. I now work at FMS developing biosensors, applying my skills as a scientist within a meaningful, collaborative biotechnology environment.

Left to Right: Eirini, Mala, Victoria, Kerry, and Sarah

Artificial Skin: How Groundbreaking Research Inspires Innovative Solutions

The biochemistry landscape moves fast, and at FlexMedical Solutions we make a point of keeping pace with new developments that could shape the future of wearable diagnostics. One area that recently caught our eye was a fascinating advance from researchers at Aalto University and the University of Bayreuth, who created a self-healing hydrogel with properties similar to human skin.

Traditionally, hydrogels have offered either high stiffness or self-healing capability — achieving both at once has been a challenge. This new material successfully combines the two, overcoming long-standing limitations and opening the door to exciting applications including drug delivery, wound healing, soft robotics, next-generation sensors and artificial skin systems.

To achieve this, we designed and built a custom test jig capable of replicating a sweat-like effect underneath the wearable patch. This allows rapid, controlled testing of different fluidic designs.

The jig uses a perforated silicone sheet, created using a fine-gauge needle to mimic sweat pores. Once assembled with a dispersion plate and an inlet on the reverse side, the silicone can be gently pressurised with fluid. As pressure builds, droplets emerge through the perforations — much like perspiration through human skin. By connecting the jig to a programmable syringe pump, we can finely tune the flow rate to replicate the sweat levels expected during exercise.

This innovative setup enables us to iterate quickly, gather meaningful data and push our wearable lactate biosensor towards robust, real-world performance. It’s another example of how cross-disciplinary research continues to inspire practical solutions in medical device development.

Step 4 – Engineering a Stable Sensor Surface.

Developing a continuous lactate-measuring biosensor for a wearable device involves several biochemical and engineering challenges. A key requirement is stabilising the functionalised electrode surface so it can be successfully integrated into the wearable module.

To operate reliably on-body, the sensor surface must be dried in a stable state and protected by a selectively permeable membrane. This membrane plays a vital role:

• Protects the biochemical surface from contaminants in the sample
• Prevents user exposure to the surface chemistries
• Acts as an “analyte super-highway”, enabling efficient lactate diffusion to the electrode
• Allows soluble by-products of the biochemical reaction to diffuse away

We have now transferred the full functionalization process onto a bespoke electrode array designed for lactate measurement and additional functionality, including fill detection and a second working electrode for supplementary analytes such as pH.

Membrane Development and Early Testing

After multiple design iterations, we’ve established an insoluble, aqueous-permeable membrane that preserves biochemical activity and allows the sensor to be dried. This makes integration into the wearable fluidic module possible, ensuring controlled sweat delivery to the electrode and reliable waste removal.

Initial dry-state testing has delivered encouraging results. The example dataset demonstrates sensor behaviour over five repeated cycles at three lactate concentrations (0, 10 and 50 mM). Between each cycle, the sample is washed away and replaced with fresh solution.

Understanding Linearity and Calibration

We’ve also observed reduced linearity at higher lactate concentrations. This behaviour typically indicates that one element in the biochemical pathway is limiting the reaction rate. While raw current responses do not need to be perfectly linear, any non-linearity will translate into increased imprecision at high concentrations once the calibration algorithm is applied.
These findings are normal during biosensor optimisation and help shape our next steps: improving linearity while ensuring precision stays comfortably within commercial requirements.

What’s Next?

In our next update, we expect to demonstrate the complete system working together:

• On-body sweat collection
• In-situ biochemical detection and current generation
• Bluetooth communication to the mobile app
• Conversion to calibrated lactate concentration
• Continuous tracking over time

This is another strong step toward delivering high-performance continuous biosensing technology in a wearable format.

Integrating an Onboard Heater into IVD Disposable Electrodes for Biomarker Detection

At Flexmedical Solutions, we’re seeing a clear shift in the diagnostics landscape. Innovators are demanding more from their disposable IVD platforms – greater sensitivity, faster results, and tighter control over assay conditions. To meet these evolving needs, one technology is gaining real traction: the integration of onboard microheaters into screen-printed electrodes.

In the fast-paced world of In Vitro Diagnostics, optimising assay performance is critical. Onboard heaters enable precise thermal control, directly within the test strip – enhancing biomolecular interactions, improving reproducibility, and accelerating results at the point of care.

Why Temperature Control Matters

Many biochemical reactions – especially enzyme-mediated assays and hybridisation-based diagnostics – are highly sensitive to temperature. By integrating a microheater directly into the electrode architecture, we can apply localised, low-power heating to drive more efficient reactions.

Take immunoassays, for example: controlled heating can improve antigen-antibody binding, leading to stronger signals and more accurate readings.

How It’s Done

The process typically involves utilising conductive materials – such as carbon, silver, or gold – onto flexible substrates like PET. The heater can be precisely patterned to align with the electrode area, ensuring even heat distribution across the sensing surface, while maintaining low power requirements.

Smarter, Simpler Devices

Perhaps the most exciting part? Onboard heating eliminates the need for bulky external hardware. This opens the door for compact, low-cost diagnostic devices, ideal for resource-limited settings or rapid, on-site testing – without sacrificing performance.

As IVD technology advances, combining thermal control with biosensing functionality in a single, disposable device will play a key role in enabling faster, more reliable biomarker detection.

What’s Next?

At Flexmedical Solutions, we know that in diagnostics, speed matters. Turning smart ideas into functional, test-ready prototypes – quickly and reliably – is what we do best.

We’re already producing onboard-heated electrodes as part of our expanding capabilities in biosensor fabrication.

Watch this space for further updates in the microheater series, as we bring this innovative technology to life!

STEP 3 – one of the key steps in developing a reusable biosensor for lactate measurement is the immobilisation of critical components on the sensor surface.

Why is this important? Traditionally, many biosensors are single-use. We make the sensor reusable, by engineering the key components to be regenerated without losing functionality. This means that when a fresh sample is applied, accurate results can still be obtained across multiple measurements. Our current work focuses on demonstrating this proof of concept, with full performance to be achieved in later stages of design and development.

Demonstrating Repeatability

Using one of our in-house immobilisation strategies, we tested sensors at three lactate concentrations. All electrodes were tested, then cleaned with a surfactant-containing buffer, before fresh samples were reapplied. Each sensor underwent five test cycles. Results showed less than 5% variation across the repeated tests – a major milestone, as it was the first time we demonstrated repeatability with reusable sensors and minimal current decay.

Linking with Our App

We then tested the reusable sensor on the FlexMedical Solutions custom App. In the example shown, four samples were applied in sequence: 0, 70, 90, and back to 0 mM Lactate. Encouragingly, when the final 0 mM sample was tested after the 90 mM reading, the sensor returned to baseline, confirming that results were not biased by the prior high concentration.

What’s Next?

This type of device is referred to as a “wet” biosensor, meaning the biochemical components are immobilised but not dried. Before moving towards a fully dry format, we need to design a semipermeable membrane. This will protect the biosensor from the effects of sweat, skin contact, and mechanical stress, while also ensuring biocompatibility to avoid unwanted skin reactions.

This marks a significant step towards wearable lactate monitoring – an innovation with potential applications in sports performance, health monitoring, and beyond.

Step 2: perform initial studies on drying of the enzyme and the other key biochemical building blocks required for sensor function.

The final sensor will be stored, shipped and used in a dry and stable format. This is essential for ease of use and long term stability and the removal of the need for cold chain shipping. While the surface chemistry of the sensor will be radically different in the final continuous measuring sensor, the non-continuous (single use) format of the sensor gives us a consistent platform in order to characterize the strategies we intend to use to immobilize, embed, dry and stabilize the final sensor. For this work we use our off-the-shelf carbon electrode that is constructed of the material that are anticipated to be used in the final wearable sensor.

The above dry sensor demonstrated an LOB (limit of blank) of 3.4µM and precision means of 2.0% (raw current) and 7.4% (calibrated response). Dynamic change up to 200mM suggests linearity is expected to be >200mM. This level of performance in a dry sensor exceeded our expectations at this stage in the devices evolution.

Next we move to immobilizing the biochemically active components necessary for the repeated measurement of the biosensors (this is key to the utility of the continuous measurement element of the biosensor). We made rapid progress to this point, we expect things to get more difficult from now to the end of the project.

Donogh FitzGerald
Chief Technology Officer

When pulling together our development project, we decided that we should use lactate as our target for measurement. Lactate is a byproduct of anaerobic glycolysis which is associated with a range of clinical disease states but also has applications in sports science. Additionally, it’s recognised as one of a combination of markers linked to sepsis, so is an interesting molecule. From a biochemical point of view, it is measured enzymatically similar to many other clinical chemistry analytes. Therefore, it demonstrates proof of principle on lactate, using this as a stepping stone to rapid development of other enzymatic continuous biosensors. Lactate is present in blood, interstitial fluid, and sweat, and is therefore readily available – perfect for this project.

For the purposes of this blog, we have split the process into 5 steps:

Step 1: Electrochemical Reaction

The initial step is to establish the assay biochemistry using the core building blocks intended to be used in the final device. These core building blocks are typically: working and counter electrode material, reference electrode material, substrate, and biochemicals.

It’s a great way to kick off an assay development project as it verifies the activity and performance of the key raw materials and starts the project with positive momentum. At this stage in the project because there is still a lot of latitude, this first step should inevitably work.

This approach reflects a strong conviction that successful diagnostic device, or for any other kind of biosensor, development needs to start with the elements of the system that are abstract and underpin the core technology (the chemistry). By locking down decisions related to macro components (the test strip, the cartridge, the reader) too early you can unintentionally limit options available in the scientific solution. Get the science to do the heavy technical lifting at the start and thus allowing more flexibility around the design of the tangibles (strip, cartridge, reader) but be prepared to go fast on these elements.

Key materials were chosen that are planned to be used in the final prototype. Reagent design was based on a design structure we were confident would yield a positive outcome. In the first iteration we want to see clear dose response where precision is at a place that allows you to have confidence in the separation between concentration levels. Additionally, you should be able to demonstrate sensitivity and linearity across the intended dynamic ranges (not final performance, but sufficient to give you confidence that through further optimisation the required performance will be met). Two enzyme types were used, both with varied characteristics and benefits, and both were included in the reagent at equivalent final activity per sensor.

At this stage the development is being done on standard FMS-008 electrodes. We use these electrodes as a very stable and consistent reliable platform that allows the team to rapidly bring the biochemistry to life, and whereby we have a known pathway from wet E-chem on our “off the shelf” design to equivalent or better performance in a dry lidded bespoke biosensor format.

Our sensitivity target was achieved with both enzymes 3.4µM (Heart) and 24.7µM (Muscle); and equivalent mean % CV was achieved in this early data: 5.1% (Heart) and 3.0% (Muscle).

Linearity was observed to be qualitatively better for (Muscle) compared to (Heart).

With the core electrochemical pathway proven and biochemicals tested on the sensor materials, the next major step will be demonstrating dry performance of the enzyme.

Most biochemists can swiftly build a demonstratable wet electrochemical reagent – the real skill is to design the excipient components (and deposition and drying settings) to ensure homogeneous passive resuspension/rehydration and retention of full activity through a long shelf life in ambient storage conditions (cost effectively!)

We’ll see how good a job we’ve done in our next update…….

Donogh FitzGerald
Chief Technology Officer

In today’s rapidly evolving biotech landscape, biosensors are at the forefront of innovation – powering everything from real-time health monitoring to environmental diagnostics. As demand for accuracy, speed, and reliability grows, so does the need for robust development methodologies. Enter Six Sigma – proven framework that’s transforming how biosensors are designed and manufactured.

What is Six Sigma?

Six Sigma is a data-driven methodology focused on reducing defects, minimizing variability, and improving overall process quality. Originally developed for manufacturing, it has since been adopted across industries, including healthcare and biotechnology. For biosensor developers, Six Sigma offers a structured approach to achieving consistent, high quality outcomes – critical in a field where precision can be lifesaving. At FMS we are committed to Six Sigma and see it as a useful development tool for scientists and engineers.

Enhancing Development Efficiency

Biosensor development is inherently complex. It involves multi-disciplinary collaboration, intricate microfabrication, and rigorous testing.  Six Sigma’s DMAIC (Define, Measure, Analyse, Improve, Control) framework helps our project teams problem solve, identify inefficiencies, eliminate waste, and optimize at each stage of the development cycle.

For instance, during the prototyping phase, Six Sigma tools can be used to analyse sensor response variability, ensuring that calibration is consistent across devices. In manufacturing, it helps reduce defects in sensor assembly – quickly improving yield and reducing costs.

Accelerating Time-to-Market

Speed is a competitive advantage in biosensor innovation. However, rushing to market without quality control can lead to setbacks or worse recalls. At FMS, we believe Six Sigma mitigates this risk by embedding quality into every step of the process. which helps bring to life our “Quality First” mantra.  Techniques like Failure Mode and Effects Analysis (FMEA) and Statistical Process Control (SPC) allow teams to anticipate problems before they occur, reducing delays and rework.

The result? Faster development cycles, fewer surprises, and a smoother path to product approval.

Building Trust Through Quality

Regardless of the application of a biosensor whether human health, animal health, agri-food, or other processing environment, stringent performance standards and reliable results every time are critical. Our technical leaders believe that Six Sigma ensures that biosensors meet client requirements.  

We believe that FMS’ commitment to quality is a powerful differentiator through the entire process from development to delivery.  Customers, regulators, and consumers are backed by rigorous Six Sigma processes, assuring better outcomes.

Six Sigma processes also sit comfortably with our internal iCARE (innovation, community, accountability, respect, excellence) values.

Final Thoughts

As biosensor technology continues to push boundaries, the expectations around performance increase and the margin for error narrows. At FMS we believe Six Sigma, combined with great industry experience, provides the tools and mindset needed to navigate the challenge this presents with confidence.

By embedding Six Sigma into our development behaviours, we not only assure your product –  we elevate your brand.

Key to the components used in electrochemical-based biosensors is the underlying electrode material and fabrication process. Choosing the right material for the right analyte and chosen biochemical architecture is key. Below I’ve summarised some pros and cons of a range of different electrode materials based on my first-hand experience. While I could wax lyrically about this topic all day, I’ll stick to a list for now!

After identifying your target molecule to detect and what sample type it will be accessed in, then determine the most likely biochemical pathways I which to render is specifically and sensitively detectable in an E-chem device. At this point, determine what type of electrode material you’ll need. Make a smart and informed choice of the right material, and don’t try to force the assay to work on a single material type – assay development is hard enough!

Laser induced graphene (LIG)

• Pro: Sensitive compared to carbon, versatile process.
• Con: Fragile, limited surface options, surface needs to be pacified prior to testing (3D micro-structure makes it challenging), compatibility with downstream processes, unproven commercially.

Laser ablated Carbon nano tubes (CNT)

• Pro: Very sensitive compared to carbon, functionalization options, versatile process.
• Con: Expensive equipment outlay, Material scalability challenges, very fragile.

Laser ablated stainless steel

• Pro: Antifouling characteristics, robust material, versatile process.
• Con: Expensive equipment outlay, limited functionalization options, may contain electrochemically active species in metal.

Laser ablated platinum

• Pro: Sensitive, versatile process, catalytic activity.
• Con: Expensive, fragile, functionalization limitations.

Supplementary layers to consider and be aware of:
Introducing carbon nanotubes to the surface of carbon is a great way to enhance the sensitivity of carbon, but adds extra cost. Nanotubes also enable some solution phase functionalization prior to coupling to the surface of the electrode, giving better control and reduce cost to the functionalization process. Similarly, coupling conductive polymers (such as PEDOT:PSS) is another great way to enhance sensitivity of carbon (and to a lesser expect gold surfaces). This can be introduce in various ways depending on the functionality required.

When developing biosensors for 3rd parties, it’s important to start the journey with an electrode type that will bring the sensor to life as quickly as possible (and which has a clear line of sight to a cost effective and manufacturable design and process). Below are what I see as the strongest materials from which to start the development journey. Each biosensor and client needs are different, so as we encounter performance challenges that are potentially linked to the underlying electrode, we evaluate alternatives and pivot if necessary (All with the limits of Design Control of course!).

At FMS, we don’t really care what electrode material we use, we just want to make sure it’s right for our clients specific application. In fact, if we can’t fabricate the chosen electrode in-house, we will source and procure – with past and current examples including carbon nanotubes, pure graphene and silicon transistors.

Continuous monitoring enzymatic assays (eg: Lactate)

• What: Screen printed mediated carbon
• Why: enzyme conjugation methods established, low protein binding

Ion-selective Electrode (eg: Potassium)

• What: Electrochemically activated Laser ablated gold
• Why: Excellent precision (needed for ISE), good for membrane formation

And Remember – not all assays are suited to electrochemical detection
We do a lot of electrochemical product development and manufacturing, because its one of our super powers as an organization: these devices are robust, low cost and allow for very low cost instrumentation (glucometers!). The reality is we don’t always recommend electrochemical methods for our clients projects. We evaluate our clients vision and product concept, and working within their specifications, we routinely recommend alternative assay architectures such as optical, fluorescence, chemiluminescence and electroluminescence….again, the client is king, so where necessary we are happy to advise against electrochemistry methods if it is not suitable.

Donogh FitzGerald
Chief Scientific Officer