Traditionally, a reagent pack in a closed loop analyser system may include a barcode for identification. This helps ensure that the proper reagent pack is loaded and unloaded for consumable replacement, as well as communicating to the devicewhere the reagent is located within the machine. The method of using barcodes is quickly advancing to also leverage RFID for identification and even consumable monitoring.
Utilising an RFID-enhanced label enables virtually endless applications in regards to connectivity and communication. We will cover a few here.
1. Expiration Date:
When the RIFD label is printed, it can also encode/write the expiration date of the tagged object to the label. The encoded label is then placed on the pack itself; this expiration date can then be displayed in the reagent listing on the user interface with colour coding to visually display expired or nearly expired reagent packs. This data can even be tied into a centralised inventory management package for automated consumable reordering.
Furthermore, because the expiration date is being stored within the RFID label on the pack itself, it is then possible to read the expiration date from the RFID module on the pack, and only allow testing to continue if the pack is within the expiration parameters.
2. Incrementing Tests/Displaying Life Remaining:
It is now reasonable to include an RFID writing module on the analyser device itself. This can allow users to write an incrementing variable to the tag and then use the variable in the user interface (UI) to display useful life/number of tests remaining. For example, if a reagent pack allows for 100 tests, the tag itself can increment a “tests performed” variable, read that in the UI, and display number of tests remaining in the interface. This can be coupled with colour coding to show the number of tests remaining on a given pack.
Also, there are some closed loop systems that enable the lab to assign reagent cartridges or packs to a specific technician. In these cases, using NFC-enabled labels would allow the technician to actually see how many uses are left on their cartridges by scanning with their phone! Furthermore, this allows the option of reordering out of the scan through a web service or URI variables right through a phone.
If useful life remaining is coupled with a read step prior to using the reagent pack, the cartridge can be “killed” once the number of tests equal the approved number of tests for the pack.
3. Verifying Authenticity:
RFID can also be used to verify the authenticity of a given reagent pack. An encrypted string can be encoded in the tag that is placed on the pack which can then be used by the machine to verify authenticity. This can be done by reading the encrypted string and decrypting through the device software. Variables can be used as part of the encryption algorithm and be custom to the application through the front-end software during label printing/encoding.
4. Sensed Data:
Where the need applies, RFID tags can be coupled with sensors for an application such as temperature sensing. For example, temperature sensitive reagent packs can have a kill code written to the onboard RFID label so that if the temperature rises above or falls below specs, the kill code is activated. If a reagent pack with an active kill code identifier is loaded into the analyser, the analyser would be able to alert an error in the UI and prevent the compromised reagent pack from being used.
These are just a few ways that RFID can be leveraged in closed loop reagent packs. The applications list is ever-growing as the needs for lab automation expand and the sophistication of analyser devices increases.