New device holds promise for fast drug tests

Researchers have developed a new technique that can precisely measure the growth of many individual cells simultaneously, an advance that holds promise of rapidly testing the efficacy of a drug on patients.

The technique uses an array of suspended microchannel resonators (SMR), a type of microfluidic device that measures the mass of individual cells as they flow through tiny channels.

In the new study, published in the journal Nature Biotechnology, the researchers used the device to observe the effects of antibiotics and antimicrobial peptides on bacteria, and to pinpoint growth variations of single cells among populations, which has important clinical applications.

Slower-growing bacteria, for instance, can sometimes be more resistant to antibiotics and may lead to recurrent infections.

"The device provides new insights into how cells grow and respond to drugs," said study senior author,Scott Manalis Manalis, Professor at Massachusetts Institute of Technology (MIT).

In one experiment using the device, the researchers observed the effects of an antibiotic, called kanamycin, on E. coli that can cause diarrohea.

Kanamycin inhibits protein synthesis in bacteria, eventually stopping their growth and killing the cells.

Traditional antibiotic tests require growing a culture of bacteria, which could take a day or more.

Using the new device, within an hour the researchers recorded a change in rate in which the cells accumulate mass.

The reduced recording time is critical in testing drugs against bacterial infections in clinical settings, Manalis said.

"In some cases, having a rapid test for selecting an antibiotic can make an important difference in the survival of a patient," Manalis noted.

--IANS

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