Cell Separation by Rolling on Receptor-patterned Surfaces

Cell rolling is a physiological phenomenon exhibited by cell types such as leukocytes, stem cells, and metastatic cancer cells, involving the formation of transient adhesive bonds between the cell and the surface on which it rolls. We have discovered that patterning of adhesion receptors on surfaces can be used to direct the trajectories of rolling cells. When rolling cells encounter the edges of receptor patterns on the surface, they are forced to follow the edge through an edge effect. Our discovery may lead to new continuous-flow methods for cell separation that do not require labeling or label removal steps that are often slow and intrusive. We are currently developing cell separation techniques based on different rolling behaviors exhibited by different cell types on patterned substrates.

People: Suman Bose, Chia-Hua Lee, Minhee Sung

Collaboration: Jeffrey Karp (BWH), Robert Langer (MIT)

Microfluidic Synthesis of Polymeric Nanoparticles

Biodegradable polymeric PLGA-PEG (polylactic-co-glycolic acid-polyethyleneglycol) nanoparticles with the ability to target diseased tissues and release drugs in a controlled manner are highly promising as carriers for drug therapy. These nanoparticles have the potential to increase the efficacy of the drug and at the same time minimize adverse side effects for chemotherapy. However, the main hurdle that prevents clinical translation of these nanoparticles is their uptake by organs such as liver and spleen, which causes toxicity and is difficult to predict a priori. Control of nanoparticle properties and screening of a large number of synthesis parameters is required in order to optimize the nanoparticles to overcome this challenge. We are using microfluidic devices for synthesis of PLGA-PEG nanoparticles in order to control their properties such as size, homogeneity, and drug loading by rapid mixing of precursors during nanoprecipitation. These devices may facilitate high-throughput synthesis of nanoparticles under controlled conditions for optimization of the nanoparticles for drug delivery.

People: Pedro Miguel, Pamela Basto

Collaboration: Omid Farokhzad (BWH), Robert Langer (MIT)

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Nanofluidic Systems for Single Molecule Detection and Analysis

Resistive-pulse sensing in nanopores has the capability for detection of analytes down to the single molecule level. We are developing new techniques for analysis of biological molecules and particles in the submicron size range through the use of nanofluidic systems that can manipulate single molecules and particles. Our approach may significantly advance the ability for analysis at the single molecule level.

People: Jason Sen

Membrane Technology for Desalination

Availability of clean water is a major challenge that the world will face in this century. Reverse osmosis is the process of choice when energy efficiency is an issue. We are developing a new membrane process similar to reverse osmosis that has the potential to significantly increase the flux of water through the membrane.

People: Jongho Lee

Collaboration: KFUPM Team (Saudi Arabia-MIT)

Cell Separation Based on Size and Deformability

The biomechanical properties of cells often exhibit changes during different disease states such as cancer and malaria. However, the technology to separate cells based on deformability is still in its early stages. We are investigating the transport of cells through microchannels and developing a new method for cell sorting based on cell size and cell deformability.

People: Mohamed Raafat