Engineering swollen cubosomes using cholesterol and anionic lipids

Dispersions of non-lamellar lipid membrane assemblies are gaining increasing interest for drug delivery and protein therapeutic application. A key bottleneck has been the lack of rational design rules for these systems linking different lipid species and conditions to defined lattice parameters and structures. We have developed robust methods to form cubosomes (nanoparticles with a porous internal structure) with water channel diameters of up to 171 Å which are over 4 times larger than archetypal cubosome structures. The water channel diameter can be tuned via the incorporation of cholesterol and the charged lipids DOPA, DOPG or DOPS. We have found that large molecules can be incorporated into the porous cubosome structure and these molecules can interact with the internal cubosome membrane. This offers huge potential for accessible encapsulation and protection of biomolecules, and development of confined interfacial reaction environments

Microfluidic generation of droplet interface bilayer networks incorporating real-time size sorting in linear and non-linear configurations

In this study, a novel droplet based microfluidic method for the generation of different sized droplet interface bilayers is reported. A microfluidic platform was designed, which allows the generation and packing of picoliter lipid coated water droplets. Droplets were generated by hydrodynamic focusing coupled with selective transport along grooves according to their size. A trapping structure at the end of the groove and a fine control of the flow pressures allowed for the droplets to be successfully trapped and aligned on demand. This technology facilitates the fine control of droplet size production as well as the generation of extended networks from a variety of lipids including 1,2-diphytanoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phosphocholine in linear and non-linear configurations, which is vital to the application of Droplet Interface Bilayers to biological network construction on-chip

A transparent 3D printed device for assembling droplet hydrogel bilayers (DHBs)

We report a new approach for assembling droplet hydrogel bilayers (DHBs) using a transparent 3D printed device. We characterise the transparency of our platform, confirm bilayer formation using electrical measurements and show that single-channel recordings can be obtained using our reusable rapid prototyped device. This method significantly reduces the cost and infrastructure required to develop devices for DHB assembly and downstream study

Optically assembled droplet interface bilayer (OptiDIB) networks from cell-sized microdroplets

We report a new platform technology to systematically assemble droplet interface bilayer (DIB) networks in user-defined 3D architectures from cell-sized droplets using optical tweezers. Our OptiDIB platform is the first demonstration of optical trapping to precisely construct 3D DIB networks, paving the way for the development of a new generation of modular bio-systems

Photonically-driven Schottky diode based 0.3 THz heterodyne receiver

Photonics-based technologies are key players in a number of emerging applications in the terahertz (THz) field. These solutions exploit the well-known advantages of optical devices, such as ultra-wide tuneability and direct integration with fiber networks. However, THz receivers are mainly implemented by fully electronic solutions, where Schottky barrier diodes (SBD) are the preferred option as detectors and mixers due to their excellent response within the THz range at room temperature, and technological maturity. Here, we demonstrate an SBD-based subharmonic mixer (SHM) at 300 GHz pumped with a photonic local oscillator. The Schottky mixer is a prototype designed and manufactured by ACST GmbH, operating at 270-320 GHz. The local oscillator is generated by photomixing on a high-frequency and high-power uni-travelling-carrier photodiode (UTC-PD), providing enough power to saturate conversion loss. Minimum single-side-band conversion loss of 14.4 dB and a peak dynamic range of 130 dB have been measured. Finally, as a proof of concept we realize an all-photonics-based 5 Gbps wireless bridge, utilizing the optically-pumped SBD mixer. With this work, we prove the feasibility of high-performance hybrid Schottky-photonic THz receivers, incorporating the best of both worlds