In the course of the project, the PRIME consortium has generated concrete results we aim to exploit towards the effective implementation of this active microfluidics technology—though exploitation in other application fields is also envisioned. In pursuit of the PRIME mission, we recognize the strategic significance of fostering collaboration and establishing licensing agreements with key industry stakeholders. These strategic partnerships will help to accelerate the adoption of our innovations in the market.
4D printed light-driven autonomous fluidic functions
PRIME developments have led to an unprecedented active valve technology based on liquid crystal elastomers that exhibit large deformations in response to light. This patented technology marks a significant leap in the realm of active microfluidics, introducing the revolutionary concept of 4D printing of responsive materials to embed the fluidic functions into the chip.[1] In the pursuit of integrated active chip components, achieving substantial and rapid shape morphing capabilities is of paramount importance. PRIME innovations have meticulously developed new inks and printed actuators that demonstrate remarkable mechanical response. These advancements in material science and processing techniques are closely intertwined with cutting-edge modeling approaches, aimed at bridging the gap between the developed materials and the realization of functional active fluidic elements.
Within this context, the PRIME consortium has successfully engineered various geometries and integration strategies, culminating in the creation of microfluidic devices that embody the PRIME valve concept relying on smart materials. The laboratory experiments conducted by the PRIME consortium have demonstrated the viability of this valve concept, with microfluidic valves capable of stopping fluid flow under constant pressure conditions. We continue working on improving the performance regarding pressure, flow and response times.
PRIME’s microfluidic valves can be integrated into the microfluidic cartridge, thereby converting this fluidic control component into a disposable entity. This integration approach facilitates the incorporation of multiple valves within the same microfluidic chip. The disposability of these valves mitigates the risk of cross-contamination that may arise with non-integrable valve systems. Furthermore, the light-actuated nature of our valves eliminates the need for bulky equipment, facilitating their integration into portable devices.
In the domain of biomedical applications, our valve technology offers both societal and commercial advantages in applications such as point-of-care devices, in vitro diagnostics, and lab-on-a-chip platforms. Additionally, PRIME microfluidic valves are relevant in diverse domains, including environmental monitoring, biosafety, and biosecurity.
Ultrasensitive and selective biosensors with colorimetric thermal transducer
PRIME reaches significantly beyond the current state-of-the-art in nanoplasmonics and biosensing by proposing the development and elaboration of cholesteric-based thermal biosensors with a potential for application in fundamental science and healthcare. Based on our patented technology,[2] the sensing elements consist of a capture antibody crosslinked to the base floor of the microfluidic channel, and a detection antibody bioconjugated to the surface of a NIR-absorbing nanoparticle (NP). When the sample is loaded, the analyte, if present, interacts with the capture antibody and is retained in the channel. Nanoparticles are subsequently retained by the detection antibody in the presence of the analyte, forming an antibody-analyte-antibody sandwich. In a later step, the channels are irradiated with an NIR laser (1064 nm). This incoming light is transduced into heat thanks to the plasmonic properties of the nanoparticles. This heat generated can change a colorimetric thermal transducer (CTT) which is the optical detection element.
So far, we have demonstrated the sensing concept for the detection of Carcinoembryonic Antigen (CEA), a common cancer marker, using a functional prototype. Within the framework of the project, we are making efforts to increase the sensitivity of detection in these systems. In addition, the operation and results obtained in the device can be executed and obtained by non-specialized users, since the particles are coupled to a thermoresponsive (thermographic) support. The use of these analytical devices is a novel concept and has been designed primarily to provide analytical capability at low cost in developing countries. The ambitious (high risk/high gain) plasmonic thermal sensing device proposed here will be prototyped by analyzing proteins. However, the underlying science involved is directly transferrable to a range of disciplines: from point-of-care clinical analysis, military and humanitarian aid field operations, to applications in art and conservation and many others where high throughput, low volumes of sample, low cost, and robustness are critical.
Thermoplastic liquid crystal elastomer actuators
Over the past decade, a substantial amount of research has been devoted to fabricating stimuli-responsive polymers with large, reversible deformations. The scientific fascination for nature’s responsive actuating systems has fueled the development of soft actuators that are readily applied in real-world applications, including artificial muscles, soft robotics, smart textiles, and devices exhibiting stimuli-triggered deformations triggered by changes in humidity, temperature, and light, for example. Although these developments are promising, soft actuators are typically thermosets containing permanent crosslinks, thus virtually unrecyclable and not moldable. The work of PhD student Sean Lugger, developed within the PRIME project, focuses on developing thermoplastic shape-changing polymers to endow smart materials with recyclable and moldable features, affording sustainable soft actuators with a staggering variety of functionalities.
For this, melt-processable thermoplastic soft actuators are introduced, demonstrating immediate, reversible responses and weightlifting capabilities with large deformations upon exposure to light or temperature changes. The thermoplastic material could be recycled, reprogrammed into 3D actuators, and welded. 3D-printing can be used to prepare the actuators. To further push the applicability of soft actuators toward standard industrial processes, melt-extrusion and drawing of thermoplastic actuator fibers on a large scale are also possible.
Overall, Sean’s findings reveal a new class of thermoplastic LCEs achieving more sustainable soft actuators with melt-processable properties and recyclable, reusable capabilities. It is envisioned that these materials will serve as a starting point for industrially-relevant smart materials that are widely applicable in our society for myriad applications such as soft robotics, smart textiles, artificial muscles, and deployable microfluidic devices.[3]
PRIME member and PhD student Sean Lugger in the lab
References:
[1] C. Sánchez-Somolinos, I. Ochoa, L. Fernández, M. Doblaré, Microfluidic valve, method for its manufacture, and uses thereof. WO 2021/260249.
[2] P. del Pino, B. Peláz, E. Polo, V. Grazú, J.M. de la Fuente, V. Parro, Biosensor comprising metal nanoparticles, WO2014/016465.
[3] S. J. D. Lugger, D. J. Mulder, A. P. H. J. Schenning, Method for the Preparation of a Thermoplastic Liquid Crystalline Polymer, WO/2023/059194.