Development and implementation of ISAR, a new synthesis platform for radiopharmaceutical production.

Background: PET radiopharmaceutical development and the implementation of a production method on a synthesis module is a complex and time-intensive task since new synthesis methods must be adapted to the confines of the synthesis platform in use. Commonly utilized single fluid bus architectures put multiple constraints on synthesis planning and execution, while conventional microfluidic solutions are limited by compatibility at the macro-to-micro interface. In this work we introduce the ISAR synthesis platform and custom-tailored fluid paths leveraging up to 70 individually addressable valves on a chip-based consumable.

A solvent resistant lab-on-chip platform for radiochemistry applications.

The application of microfluidics to the synthesis of Positron Emission Tomography (PET) tracers has been explored for more than a decade. Microfluidic benefits such as superior temperature control have been successfully applied to PET tracer synthesis. However, the design of a compact microfluidic platform capable of executing a complete PET tracer synthesis workflow while maintaining prospects for commercialization remains a significant challenge.

Microfluidics: a groundbreaking technology for PET tracer production?

Application of microfluidics to Positron Emission Tomography (PET) tracer synthesis has attracted increasing interest within the last decade. The technical advantages of microfluidics, in particular the high surface to volume ratio and resulting fast thermal heating and cooling rates of reagents can lead to reduced reaction times, increased synthesis yields and reduced by-products. In addition automated reaction optimization, reduced consumption of expensive reagents and a path towards a reduced system footprint have been successfully demonstrated.

Microfluidic reactor geometries for radiolysis reduction in radiopharmaceuticals.

Autoradiolysis describes the degradation of radioactively labeled compounds due to the activity of the labeled compounds themselves. It scales with activity concentration and is of importance for high activity and microfluidic PET tracer synthesis. This study shows that microfluidic devices can be shaped to reduce autoradiolysis by geometric exclusion of positron interaction.

Silicon-based microfilters for whole blood cell separation.

This paper reports on the comparison analysis of four main types of silicon-based microfilter for isolation of white blood cells (WBCs) from red blood cells (RBCs) in a given whole blood. The microfilter designs, namely, weir, pillar, crossflow, and membrane, all impose the same cut-off size of 3.5 mum to selectively trap WBCs.

Novel intra-tissue perfusion system for culturing thick liver tissue.

Innovative scaffold fabrication, angiogenesis promotion, and dynamic tissue culture techniques have been utilized to improve delivery of media into the core of large tissue constructs in tissue engineering. We have developed here an intra-tissue perfusion (ITP) system, which incorporates an array of seven micron-sized needles as a delivery conduit, to improve mass transfer into the core of thick liver tissues slices (>>300 microm mass transport limit). The ITP system improves the uniformity and distribution of media throughout the tissue, resulting in improved cell viability over the static-cultured controls.

A novel 3D mammalian cell perfusion-culture system in microfluidic channels.

Mammalian cells cultured on 2D surfaces in microfluidic channels are increasingly used in drug development and biological research applications. These systems would have more biological or clinical relevance if the cells exhibit 3D phenotypes similar to the cells in vivo. We have developed a microfluidic channel based system that allows cells to be perfusion-cultured in 3D by supporting them with adequate 3D cell-cell and cell-matrix interactions.

Magnetic-based microfluidic platform for biomolecular separation.

A novel microfluidic platform for manipulation of micro/nano magnetic particles was designed, fabricated and tested for applications dealing with biomolecular separation. Recently, magnetic immunomagnetic cell separation has attracted a noticeable attention due to the high selectivity of such separation methods. Strong magnetic field gradients can be developed along the entire wire, and the miniaturized size of these current-carrying conductors strongly enhances the magnetic field gradient and therefore produces large, tunable and localized magnetic forces that can be applied on magnetic particles and confine them in very small spots.

An integrated microfluidic platform for magnetic microbeads separation and confinement.

An innovative microfluidic platform for magnetic beads manipulation is introduced, consisting of novel microfabricated 3D magnetic devices positioned in a microfluidic chamber. Each magnetic device comprises of an embedded actuation micro-coil in various design versions, a ferromagnetic pillar, a magnetic backside plate and a sensing micro-coil. The various designs of the micro-coils enable efficient magnetic beads trapping and concentration in different patterns.

The nature of the gecko lizard adhesive force.

The extraordinary climbing skills of gecko lizards have been under investigation for a long time. Here we report results of direct measurement of single spatula forces in air with varying relative humidities and in water, by the force-distance method using an atomic force microscope. We have found that the presence of water strongly affects the adhesion force and from analysis of our results, we have demonstrated that the dominant force involved is the capillary force.

A configurable three-dimensional microenvironment in a microfluidic channel for primary hepatocyte culture.

We have developed a technique for the in situ three-dimensional (3D) immobilization of primary rat hepatocytes within a localized matrix in a microfluidic channel that provides a 3D microenvironment incorporating both a configurable 3D matrix and fluid perfusion. This is based on the laminar flow complex coacervation of a pair of oppositely charged polyelectrolytes, i.e.