SaPher Biosensing System is be divided in two main components:
- The Consumable Cartridges, which are composed of the Photonic Integrated Circuit (PIC) which relies on optical physics, the microfluidics system, and specific antibodies.
- SaPher Biosensing Platform as a read-out system of the cartridges, which involves optoelectronics elements (laser, collimators and photodetectors) for PIC interrogation, electronic control with firmware, data and signal processing software and human-machine interface (HMI), has an estimated production cost of €5.100 (Table 2 – on the right).
- Photonics Integrated Circuit. SaPher technology is based on an optical transducer and optical physics to transform biochemical interactions (e.g. detection of the allergen by a specific antibody) in an optically measurable The Ring Resonators together form the effective sensing area of the PIC. For the biofunctionalization of the RR, the surface of the PIC needs to be chemically treated, to enable the immobilization of the antibodies onto the RR sensing area by means of a micro-imprinting device. When the liquid food sample flows over the RR, the target analytes bind onto immobilized antibody changing the light transmission properties. This change in transmission properties enables the system to calculate the concentration of analytes within the range of a part per billion. In addition, the use of biofunctionalized RR enables the determination of the different analytes without the use of fluorescent or colorimetric markers (being label-free) in contrast to other immunological techniques (e.g. ELISA, PCR, LFD).
- Microfluidics. To identify and quantify the allergen content, it is essential for food sample in liquid form to flow over the sensing area of the PIC. The microfluidics design of the cartridge consists of 2 food sample reservoirs and 2 buffer reservoirs, attached to each other in pairs and to the fluidic channels and ending up in a waste reservoir. All the fluids are contained in the cartridge, avoiding any possible contact with the biosensing platform and hence avoiding any contamination issues, a key of the unit.
- SaPher cartridges operation. The cartridges are designed with the objective of facilitating its usage and to enable the assessment of up to 6 different allergens simultaneously. Therefore, the single-use disposable cartridges integrate LUME´s proprietary PIC, which includes the bio-functionalized RR, the channels and the reservoirs for the fluidics. The sensing areas of the cartridge, RR, will have been independently biofunctionalized with specifically designed antibodies for the target allergens prior to its usage. The assay begins by making the liquid sample flow over the sensing area, where target analytes will bind to the corresponding antibodies and so light transmission properties changes. All these steps are performed automatically within 30 minutes.
- SaPher cartridges product line. As an outcome of the project implementation, we shall deliver the full product line of SaPher with cartridges in four different configurations for all the allergen assessment needs of bakery, dairy and meet sectors (A total number of 11 allergens).
SaPher Biosensing Platform
For the fully automated handling of the cartridges, avoiding the need for any human intervention, the platform will rely on a tray-based positioning system. Also, the platform shall automatically take charge from its positioning, measurement and its returning after the complete process for its proper disposal. This will not only improve usability, but also robustness, avoiding any possible damage to key components, since these are inaccessible to the operator.
- The PIC interrogation system consists of a tunable laser that interrogates the PIC. The resulting light signal (modified by the binding of analytes on to the RR) is then independently measured by a set of photodetectors. The resulting light signal shall then be converted by the photodetectors into an electrical signal for its further processing and interpretation.
- The processing of the read signal is performed by our own developed algorithms and software, incorporating for its execution a low-cost embedded computer. SaPher, as any other measurement method, requires to be calibrated to establish its specific response against known concentrations of a given analyte. Therefore, a previous remote calibration of the equipment, PIC and analyte set will be necessary on a yearly basis. The cartridges are labelled with a QR code, which upon being scanned, enables the sensing platform to automatically configure itself to match all test related parameters, such as allergen types, calibration curves, etc.
- The Human Machine Interface enables the test visualisation process, as well as the individual graphical representation across time (sensograms), providing clear conclusions on the identification and quantification of positive allergen contents. The operator shall only be required to scan the QR code to start the process, without the need to alter any operational parameter. Finally , the operator shall have the options to either download the results on USB, send them via Wi-Fi to the corporates´ Enterprise Resource Planning (ERP) software or print them out and assess appropriately, how to have their products label.
LUMENSIA In conjunction with UPV have already developed a functional and automated prototype of SaPher biosensing System (cartridge and biosensing platform) for multi-allergen detection in food matrices. They have in addition collaborated with INGE for the initial development and bio-functionalization of 4 allergen antibodies (Ovalbumin – egg, Gluten – cereal, Casein and β-lactoglobulin – milk), which corresponds with the SAPHER C01 cartridge. This functional prototype, which has been built upon the technological advances achieved in the framework of multiple European and Spanish funded projects, has had its functioning and specs demonstrated under relevant conditions, taking samples of all meat products from the company ¨Embutidos Martínez¨ (one of LUME´s shareholders), reaching TRL6. During the demonstration, real samples were analysed on the 4 mentioned allergens, and the results compared with official labs, showing in all cases consistent and accurate results.