Abstract:
:We have used a microfluidic mass sensor to measure the density of single living cells. By weighing each cell in two fluids of different densities, our technique measures the single-cell mass, volume, and density of approximately 500 cells per hour with a density precision of 0.001 g mL(-1). We observe that the intrinsic cell-to-cell variation in density is nearly 100-fold smaller than the mass or volume variation. As a result, we can measure changes in cell density indicative of cellular processes that would be otherwise undetectable by mass or volume measurements. Here, we demonstrate this with four examples: identifying Plasmodium falciparum malaria-infected erythrocytes in a culture, distinguishing transfused blood cells from a patient's own blood, identifying irreversibly sickled cells in a sickle cell patient, and identifying leukemia cells in the early stages of responding to a drug treatment. These demonstrations suggest that the ability to measure single-cell density will provide valuable insights into cell state for a wide range of biological processes.
journal_name
Proc Natl Acad Sci U S Aauthors
Grover WH,Bryan AK,Diez-Silva M,Suresh S,Higgins JM,Manalis SRdoi
10.1073/pnas.1104651108subject
Has Abstractpub_date
2011-07-05 00:00:00pages
10992-6issue
27eissn
0027-8424issn
1091-6490pii
1104651108journal_volume
108pub_type
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