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The new and rapid advancement in the complexity of biologics drug discovery has been driven by a deeper understanding of biological systems combined with innovative new therapeutic modalities, paving the way to breakthrough therapies for previously intractable diseases. These exciting times in biomedical innovation require the development of novel technologies to facilitate the sophisticated, multifaceted, high‐paced workflows necessary to support modern large molecule drug discovery. A high‐level aspiration is a true integration of “lab‐on‐a‐chip” methods that vastly miniaturize cellulmical experiments could transform the speed, cost, and success of multiple workstreams in biologics development. Several microscale bioprocess technologies have been established that incrementally address these needs, yet each is inflexibly designed for a very specific process thus limiting an integrated holistic application. A more fully integrated nanoscale approach that incorporates manipulation, culture, analytics, and traceable digital record keeping of thousands of single cells in a relevant nanoenvironment would be a transformative technology capable of keeping pace with today's rapid and complex drug discovery demands. The recent advent of optical manipulation of cells using light‐induced electrokinetics with micro‐ and nanoscale cell culture is poised to revolutionize both fundamental and applied biological research. In this review, we summarize the current state of the art for optical manipulation techniques and discuss emerging biological applications of this technology. In particular, we focus on promising prospects for drug discovery workflows, including antibody discovery, bioassay development, antibody engineering, and cell line development, which are enabled by the automation and industrialization of an integrated optoelectronic single‐cell manipulation and culture platform. Continued development of such platforms will be well positioned to overcome many of the challenges currently associated with fragmented, low‐throughput bioprocess workflows in biopharma and life science research.

Shear stress plays a critical role in regulating platelet adhesion and thrombus formation at the site of vascular injury. As such, platelets are often examined in vitro under controlled shear flow conditions for their hemostatic and thrombotic functions. Common shear-based platelet analyses include the evaluation of genetic mutants, inhibitory or experimental compounds, matrix substrates, and the effects of different physiological and pathological shear forces. There are several laboratory instruments widely used for studying shear flow, including cone and plate viscometers and parallel plate perfusion chambers. These technologies vary widely in the types of samples, substrates, blood volumes, and throughput that are involved. Here, we describe a microfluidic system for platelet analysis under shear flow. We used the devices to study thrombus formation on collagen I and von Willebrand factor. The system was also used to investigate dose response to the antiplatelet compound, Abciximab, under shear flow conditions with an emphasis on maximizing the number of data points per single patient sample. The presented method confers multiple advantages over conventional approaches. These include the ability to assess up to 24 conditions simultaneously in real time, maintain identical physical conditions across experiments, and use extremely low donor volumes.

Ion channel assays are essential in drug discovery, not only for identifying promising new clinical compounds, but also for minimizing the likelihood of potential side effects. Both applications demand optimized throughput, cost, and predictive accuracy of measured membrane current changes evoked or modulated by drug candidates. Several competing electrophysiological technologies are available to address this demand, but important gaps remain. We describe the industrial application of a novel microfluidic-based technology that combines compounds, cells, and buffers on a single, standard well plate. Cell trapping, whole cell, and compound perfusion are accomplished in interconnecting microfluidic channels that are coupled to pneumatic valves, which emancipate the system from robotics, fluidic tubing, and associated maintenance. IonFlux™ is a state-of-the-art, compact system with temperature control and continuous voltage clamp for potential application in screening for voltage- and ligand-gated ion channel modulators. Here, ensemble recordings of the IonFlux system were validated with the human Ether-à-go-go related gene (hERG) channel (stably expressed in a Chinese hamster ovary cell line), which has established biophysical and pharmacological characteristics in other automated planar patch systems. We characterized the temperature dependence of channel activation and its reversal potential. Concentration response characteristics of known hERG blockers and control compounds obtained with the IonFlux system correlated with literature and internal data obtained on this cell line with the QPatch HT system. Based on the biophysical and pharmacological data, we conclude that the IonFlux system offers a novel, versatile, automated profiling, and screening system for ion channel targets with the benefit of temperature control.

The study of platelet behavior in real-time under controlled shear stress offers insights into the underlying mechanisms of many vascular diseases and enables evaluation of platelet-focused therapeutics. The two most common methods used to study platelet behavior at the vessel wall under uniform shear flow are parallel plate flow chambers and cone-plate viscometers. Typically, these methods are difficult to use, lack experimental flexibility, provide low data content, are low in throughput, and require large reagent volumes. Here, we report a well plate microfluidic (WPM)-based system that offers high throughput, low reagent consumption, and high experimental flexibility in an easy to use well plate format. The system consists of well plates with an integrated array of microfluidic channels, a pneumatic interface, an automated microscope, and software. This WPM system was used to investigate dynamic platelet behavior under shear stress. Multiple channel designs are presented and tested for shear loads with whole blood to determine their applicability to study thrombus formation. Normal physiological shear (0.1-20 dyn/cm(2) ) and pathological shear (20-200 dyn/cm(2) ) devices were used to study platelet behavior in vitro under various shear, matrix coating, and monolayer conditions. The high physiological relevance, low blood consumption, and increased throughput create a valuable technique available to vascular biology researchers. The approach also has extensibility to other research areas including inflammation, cancer biology, and developmental/stem cell research.

Platelet aggregation occurs in response to vascular injury where the extracellular matrix below the endothelium has been exposed. The platelet adhesion cascade takes place in the presence of shear flow, a factor not accounted for in conventional (static) well-plate assays. This article reports on a platelet-aggregation assay utilizing a microfluidic well-plate format to emulate physiological shear flow conditions. Extracellular proteins, collagen I or von Willebrand factor are deposited within the microfluidic channel using active perfusion with a pneumatic pump. The matrix proteins are then washed with buffer and blocked to prepare the microfluidic channel for platelet interactions. Whole blood labeled with fluorescent dye is perfused through the channel at various flow rates in order to achieve platelet activation and aggregation. Inhibitors of platelet aggregation can be added prior to the flow cell experiment to generate IC50 dose response data.

We present an integrated microfluidic cell culture and lysis platform for automated cell analysis that improves on systems which require multiple reagents and manual procedures. Through the combination of previous technologies developed in our lab (namely, on-chip cell culture and electrochemical cell lysis) we have designed, fabricated, and characterized an integrated microfluidic platform capable of culturing HeLa, MCF-7, Jurkat, and CHO-K1 cells for up to five days and subsequently lysing the cells without the need to add lysing reagents. On-demand lysis was accomplished by local hydroxide ion generation within microfluidic chambers, releasing both proteinacious (GFP) and genetic (Hoescht-stained DNA) material. Sample proteins exposed to the electrochemical lysis conditions were immunodetectable (p53) and their enzymatic activity (HRP) was investigated.

Chemical gradients that run axially in a microfluidic channel often contain undesirable high-frequency concentration variations, or noise, that results from mechanical and thermal fluctuations in the system. In this paper, we describe a passive microfluidic component called an 'expansion channel' (EC), that removes high frequency noise through axial dispersion. We show that the behavior of the filter can be modeled analytically, using an expression for the transfer function of the microfluidic channel, derived by Xie et al. (Y. W. Xie, L. Chen and C. H. Mastrangelo, Lab Chip, 2008, 8, 907-912). The use of ECs to remove noise from gradients formed in enyzmatic assays in a microfluidic channel is demonstrated. The resulting data quality is improved which enables better fits to chemical models and more accurate analysis. ECs should be very effective in removing noise from axial concentration gradients found in many microfluidic applications, e.g. liquid chromatography, biochemistry, and chemotaxis studies.