Early Questions to Ask When Developing Diagnostic Products

It’s best to ask the toughest questions early in the process of developing diagnostic systems when assay and detection technologies are developed in parallel with use case definition.

But which questions should you be asking?

Below are just a few examples. These questions help identify product features and development risks requiring mitigation before the product architecture can be fully defined. They are intended to be conversation starters among the many parties involved in development: assay scientists, marketing managers, instrument and cartridge developers, usability engineers and industrial designers.

Help with the Right Questions

1. User – Products must be intuitive to use or they won’t be adopted in the market — or worse, a patient could be harmed from misuse. It is imperative to fully understand the use case to build a product that works well with the intended user.

a. What user training level can be expected? Can users be relied upon to navigate the desired user interface?
b. What user steps are ripe for errors, and how can design mitigate them?

2. Environment – Designing a point-of-care product for decentralized settings is a lot different from designing for high-throughput central lab settings. In both cases, it is important to design for the intended use environment so that issues like shipping conditions or power management don’t creep up late in the design process.

a. Where will the product live: Benchtop? Portable? Home? Patient room? Indoors? Outdoors? If portable, how long does the battery need to last? When and where will it be recharged?
b. What are the expected temperature, humidity and pressure conditions and how could they affect assay performance?

3. Data Management – Diagnostic information is highly confidential, so everything from data storage to the way that information is displayed must be considered at the outset. Further, data management decisions affect the entire product architecture. For example, connectivity means wireless cards and UI navigation requires LCD displays, which in turn affect power budgets and enclosure designs.

a. When does data need to be transferred to a central database? How will data be transferred from the device – wired or wireless?
b. What security features need to be implemented to manage sensitive data?
c. What backup measures must be in place if a portable product loses power or connectivity?
d. What are the pros and cons of using a smart phone as the instrument UI?

4. Cartridge – If the assay will run on a disposable cartridge, the instrument must accept and manipulate the cartridge at multiple interfaces. Early in development it is important to clearly identify cartridge cost and performance targets, which will then dictate what features remain on the cartridge or shift to the instrument.

a. What assay steps might be sensitive to integration into a cartridge, and what testing can be done now to evaluate this?
b. How to design the cartridge to simplify fluid management and limit the number of instrument interfaces?
c. What materials and manufacturing methods most effectively keep costs down?

5. Reagents – Key reagent storage and handling questions must be addressed early. These will dictate cartridge and instrument designs. For example:

a. What temperatures will reagents be exposed to during device operation?
b. How will reagents be introduced into the diagnostic cartridge? Will dried down or lyophilized reagents already be inside, or will they be dispensed in from a separate source? How to separate wet and dry constituents effectively?
c. How must reagents be stored and transported while not in use? Do they need to be refrigerated? Frozen? Kept at room temp?

6. Sample – Blood, urine, saliva or stool sample collection must be intuitive and the cartridge sometimes must accommodate multiple sample types. Early on, it is important to understand the assay sensitivities to sample types and volumes, so tricks like fluid metering can be implemented in sample handling.

a. How will the sample be collected? Is a precise volume of fluid required?
b. How can the user intuitively load, wick, dispense, or pipette the sample into the cartridge?

Initiating discussions around these topics early is important. Contact Key Tech if you have unique challenges, and we can begin asking the right questions for your application.dx_jp

Abbie Shoemaker

Abbie Shoemaker

Abbie has experience designing analog and digital hardware to meet the challenges of the medical and consumer device markets. She is particularly interested in medical device design and the development of “green” technologies. Abbie graduated Summa Cum Laude from the University of Pittsburgh with a BS in Electrical Engineering and a minor in Bioengineering.
Abbie Shoemaker


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