Lab-on-a-chip takes next step

PALO ALTO, Calif.—The lab-on-a-chip (LOC) field may be about to hit its stride with the recent introduction of a fully automated system by Agilent Technologies. Designed to replace gel electrophoresis steps, the Agilent 5100 ALP allows researchers to perform thousands of unattended protein and DNA analyses daily, fulfilling the high-throughput requirements of many drug discovery labs.

 

"Current customer workflows in genomics and proteomics employ classic 1-D slab gel electrophoresis for proteins, DNA, and RNA," explains Dr. Carsten Buhlmann, product manager for Lab-on-a-Chip Assays at Agilent. "The methodology inherently becomes a bottleneck for a significant portion of the users because it is manual labor-intensive, slow and has poor accuracy and reproducibility.

 

"These same customers are facing significant pressure to increase productivity and throughput. The quality of results—reproducibility and accuracy—has to be increased to avoid false results, and better, more comparable data is enabling completely new applications."

 

In developing the 5100 ALP, Agilent added a number of features beyond the abilities of their 2100-series bioanalyzer, including reusable chips (up to 6000 samples), unattended operation of up to twelve 96- or 384-well plates, better sensitivity and reproducibility, and sophisticated data management with an integrated database.

 

Although Buhlmann is quick to note the increasing number of research papers that feature Agilent ALP systems, he also admits that LOC technologies have not been accepted by the life science communities as quickly as many had hoped.

 

"It was a disruptive technology and it took a while to convince users to switch from their traditional methods," he says. "There are a lot of good ideas in the scientific community and some projects are in the investigation phase, but only a few products really made it to market. The reason might be some underestimation of development efforts in terms of reproducibility and usability, as well as some overestimation of the value for a selected market segment."

 

But Chris Heid, director of marketing at microfluidics specialist Fluidigm, thinks the design and ability of the chips themselves may be hindering wider adoption.

 

"Most microfluidic companies provide tools that miniaturize only one feature," he explains. "What this means is that there is a limitation in the number of experimental steps and complexity of experiments that can be done on the chip.

 

"I believe that microfluidics will really take off once chips are integrated with many different types of features so that more complex and novel functions can be performed," he adds.

 

According to Agilent's Buhlmann, the next LOC innovations will likely move from on-chip electrophoresis and flow cytometry toward on-chip chromatography and integration with other detection systems. As an example, he offers Agilent's new HPLC-Chip/MS system, a microfluidic device for nanoflow electrospray LC/MS that integrates an enrichment column, analytical column, hydraulic connections, and electrospray emitter on a single polymer chip.