Research that includes:

  • Immunosensors
  • Single Cell Analysis
  • Cell Manipulation and Probing
  • SERS BioImaging
  • Micro Total Analysis Systems uTAS
  • DNA Transformations
  • Cell Cryropreservation
  • Optoelectronic Transport & Tweezers

BPN355: Microfluidic Cell Analysis Platform: On Chip Cell Culture and Electrochemical Lysis

J. Tanner Nevill

Cultured cells are used in a variety of contexts ranging from high throughput screening of drugs to systems biology. Microfluidic devices for cell culture studies offer numerous advantages over plate-based cell culture, and because of this, are being increasingly used in laboratory settings.4,5 Microfluidic devices can provide physiologically relevant microenvironments by allowing for constant perfusion and 3D tissue-like structure. Additionally, time and costs are reduced due to decreased reagent volumes and automated handling. Higher surface-to-volume ratios can also offer improved...

BPN430: In-vivo Cellular Mapping of Biological Activity by Quantized Plasmon Quenching Dips Nanospectroscopy

Liz Y. Wu
Yeonho Choi

In a biological cell, enzyme systems play an important role since they direct the metabolism of the cell by controlling all processes to occur at a specific rate. One of the important research fields in cell biology is to investigate the structure and function of complex enzyme systems. However, the dynamic activities of enzymes in a living cell are hard to record. In this project, we probe NADH-Cytochrome b5 Reductase enzyme activity in a living cell by quantized plasmon quenching dips nanospectroscopy, a technology we developed earlier to detect the type of molecules conjugated on...

BPN417: Spatially Targeted Microfluidic Stimulation for Quantitative Gap Junction Analysis

Sisi Chen

Gap junctions are expressed in most mammalian cells, coupling their intracellular environments to allow direct communication of ions, metabolites, and other small molecules. Although gap junctions have been implicated in a range of diseases from neuronal degeneration to cancer, our understanding of their function is still incomplete. We present here the application of a microfluidic device for assaying gap junction communication by focusing dye molecules or other membrane diffusiblefocusing dye molecules or other membrane diffusible biomolecules over cells cultured to confluence. A...

BPN407: Modular-Based Integration of CMOS Chip with Microfluidics for Immunosensing

Amy Wu
Lisen Wang

The project aims to develop an integration method for CMOS chip and microfluidics, specifically for immunosensing system with microfluidic system for sample preparation and CMOS magnetic sensor for detection. Solving the size mismatch between CMOS chip (typically mm scale) and microfluidics (cm scale) while maintaining the functionality and interconnect metallization of CMOS, as well as seamlessly delivery the fluid to the sensor surface on the CMOS chip through microfluidics are the key considerations for the integration. On the other hand, the integrated biosensor will be a...

BPN476: Integrated Plasmonic Optical Trapping (iPOT)

John R. Waldeisen
Benjamin M. Ross

We are developing a multiplexed integrated plasmonic optical trapping (iPOT) device, which has the capability of optically modulated size-selective cellular trapping. This device utilizes the non-uniform radiation forces generated on a localized cell body of certain dielectric properties by the scattered electromagnetic field when an array of integrated nanoplasmonic structures is irradiated with white light (or a specific NIR laser). The trapping capability is maximized by tuning the plasmon resonance frequency of the integrated nanostructures in tightly packed, high density...

BPN478: Synthetic Microbial Pattern Formation Modulated by a Chemical Micro-interface

Taesung Kim

We develop a technique for producing synthetic microbial patterns by means of direct activation and inactivation of gene expression in an initially homogenous population of cells using a microfluidic chemical interface system. A strain of E. coli was engineered such that the presence of the membrane diffusible molecule acyl-homoserine lactone (AHL) activates the production of more AHL, thereby creating a positive feedback loop. Since the half-life of AHL decreases in high pH solutions, this feedback loop can be inhibited in a specific area by modulating the local pH using a...

BPN509: Plasmonic Transfection With Single Cell Resolution

Adrian M.E. Sprenger

Plasmonic transfection with single cell resolution can greatly benefit studies of the dynamic between a single cell and its surrounding tissue. We will develop a photoactive nano structured substrate for culture of adherent cells that enables transfection with single cell resolution, maximum cell viability and minimum expenses.

Project end date: 08/11/09

DAH5: Bioassay Based on Magnetic Recording Technology

Mei-Lin Chan

This project aims to develop a magnetic scanning probe microscope based on a magnetic tunnel junction (MTJ) sensor for the detection of magnetically-labeled biomolecules. Paramagnetic particles are employed as markers and incorporated with commercial DNA microarray technology to produce magnetically labeled DNA microarrays. An external magnetic tunnel junction is mechanically scanned across these arrays to detect and map out the localized magnetic fields from these particles. This new approach offers the potential to image centimeter-scale arrays of thousands of DNA spots while still...

BPN395: MEMS Poly/Nano: Micro Flow Lysometer for Single-cell Analysis

Won Chul Lee

This project presents a new single-cell analysis tool, flow-lysometry, for the cytosolic ATP measurement. Single-cell analysis by flowcytometry has revolutionized the measurement of complex cell populations. Only limited probes are available for the measurement of cytosolic components in single cells. While cellular components such as ATP can be measured sensitively in a suspension of cells with permeabilized plasma membranes, the determination of the distribution of such compounds in individual cells in a heterogeneous population is not available. We propose the development a novel...

BPN450: A Microsystem for Sensing and Patterning Oxidative Microgradients During Cell Culture

Jaehyun Park

We present a microsystem capable of electrochemically patterning dissolved oxygen gradients during cell cultures. Multiple electrodes in an array each generate distinct amounts of dissolved oxygen via electrolysis; these different sources superimpose to generate one- and two-dimensional microgradient profiles not possible with other methods. We believe this is the first technology that enables researchers to pattern localized oxygen doses and program arbitrary oxygen gradients with microscale resolution during cell culture.

Project end date: 02/03/10