Microfluidics deals with small amounts of fluids at the microscale. Miniaturization brings in many advantages such as reduced reagent use, shortened analysis time, increased throughput, and portability, making it an ideal enabling platform for a wide range of applications such as life science research, drug screening, and assistive technology. This talk summarizes Ren’s work on microfluidics which is dedicated to droplet microfluidics, protein fractionation, microwave sensing, and soft wearable robots for well-being. Droplet microfluidics will focus on unique active control of individual droplets with visual feedback, protein fractionation techniques will include isoelectric focusing, counterflow gradient focusing and pH elution, microwave sensing will discuss its application to metal, plastic and virus sensing, and soft robots will discuss low-cost systems for treating breast cancer-related lymphedema and providing a personalized fit of the prosthetic socket for amputees.

Real-time monitoring of a patient’s biofluids such as blood, platelets, urine, serum, teardrops, etc. is critical for healthcare professionals who need a fast, low-cost, and easy way to measure key biomarkers at the point of care. Therefore, having a reliable, accurate, and inexpensive on-chip mixer that is capable of passively mixing any biofluid with necessary reagents is vital in order to monitor these parameters, especially in remote areas where access to high-tech or specialized lab equipment might be limited. In this work, we discuss the design, development, and testing of 3D printed passive micromixers capable of successfully performing biofluid mixing in under 5s. Our work presents a novel 3D printed micromixer for rapid and low-cost passive biofluid mixing that has the potential of advancing novel point-of-point care diagnostics

Liquid metals (LMs) have received a lot of attention over the past decade. Gallium-based LMs are promising materials with high surface tensions, low viscosities and high electrical conductivity with applications in microelectromechanical systems (MEMS) and Liquid Metal Microfluidics (LMMF). However, several challenges should be tackled to generate reproducible and non-alloying plugs with a precise control over the size and spacing of the plugs in microchannels. They swiftly oxidize in air and form a nanometer-thick layer of gallium-oxide which lower the surface tension. In this talk, I present the history of LMMF and recent results about applications of LMs in Bio-MEMS.

Biosensors using silicon photonics (SiP) technology have shown great promise, including the potential to bring the accurate, data-rich diagnostics of lab-grade assays to the point-of-need. In this presentation, we will discuss our work to address three key challenges of SiP biosensors. First, we are tuning the photonic design to meet important performance criteria. Next, we review techniques to functionalize SiP devices, and present our integration of microfluidics with the millimeter-scale sensor chips. Finally, we are using electronic-photonic integration to mitigate a key challenge for point-of-need SiP sensors: the cost and size of the readout system.

Increased adoption of optical coherence tomography (OCT) by the medical community has been hampered by its high price and bulky form factor. We aim to build an on-chip OCT system using silicon photonics technologies. Our on-chip OCT system includes three components: a spectrometer, a tunable delay line reference arm, and an optical phased array (OPA) beam scanner. In this abstract, we describe the design of the on-chip spectrometer. We design a digital Fourier transform (dFT) spectrometer centered at 1310nm (100nm bandwidth), with 1024 spectral channels, and 0.0977nm spectral resolution providing up to 108.45dB sensitivity and an axial resolution of 8.8µm.

The fields of flexible electronics and microfluidic-based labs-on-a-chip continue to advance with new devices and systems-level technologies. However, much of this advancement is limited to each of these fields separately, rather than combining flexible electronics and microfluidics together to realize wearable sensors and sensor systems. We present new approaches for combining electronics and microfluidic devices together on wearable textile-based substrates, resulting in combined systems that are highly portable, mechanically flexible, and can be easily integrated with clothing. Application areas include health care, worker safety, food safety, consumer devices, personalized medicine and biomedical and environmental monitoring. We present technologies for specific applications that include: lighting and health monitors for safety vests; heart and perspiration (pH, lactate) monitors for athletic clothing; and wearable bioelectric and biochemical monitoring.

Pre-clinical research is often conducted in two-dimensional (2D) cancer cell cultures or in animal models to identify the molecular pathways that underlie the onset and course of a disease or to assess the effectiveness of experimental therapies. However, the reductionist 2D method may distort interactions between cells and integrins and does not recreate 3D cell morphology or match the natural in situ environment of tissues. Despite the fact that animal models offer the natural 3D milieu in which cells reside, interspecies differences, cost, and ethical concerns continue to be important barriers to the development of these models. Therefore, there is a critical need for creating bioengineered in vitro models that can use biomaterials and cells obtained from humans to replicate the 3D cytostructure and microenvironment of diseases. In this talk, I will give an overview of our work on microphysiological tissue models for drug screening in this lecture. To this end, I will discuss the c

Uveal melanoma is the most common intraocular cancer in adults and may cause vision loss as well as death due to distant metastases. Early detection of tumors is critical for vision preservation and may reduce mortality. Many patients with uveal melanoma do not develop symptoms in early stages of disease when tumors are small. Diagnosis requires examination of the eye using specialized equipment and may require advanced imaging techniques. Here, we studied the electrical properties of eyes to investigate a novel, easy-to-use method for detecting uveal melanoma. We used finite element analysis to study the electrical impedance and current density in bovine eyes. We also measured the impedance and current flow in the preserved bovine eyes using a high precision impedance analyzer. Our experimental data show that a 6 mm-diameter added tissue was detected inside a 30-mm diameter eyeball by impedance analyzer, paving the way toward detection of solid tumors in eyeballs.

In this invited presentation, I will provide an overview of a new optical technology called, iCoagLAB that uses novel millifluidics for complete coagulation and platelet profiling at the point of care.

Accurate and reliable characterization of liquids is essential in pharmaceutical and industrial production sites as well as in life science laboratories. Vibrational spectroscopy techniques such as RAMAN-, Fourier Transform IR- or most recently introduced quantum cascade laser based (QCL-IR) spectrometer have been proven fulfilling good manufacturing practice standards (GMP-ready). For suspensions the spatial and chemical information of droplets and their matrix might be important, but is still ignored of commonly used spectrometers. Hence, we applied a hyperspectral QCL-IR microscope for investigating suspensions by direct absorption spectroscopy, in order to get chemical and spatial information simultaneously.