• The detection of several solutes has to be done at the low concentrations which prevail in the system.
• In this instant, several pollutants arise at ppb levels, and it is difficult to detect them at such low concentrations.
• There is a need to detect these pollutants on site using compact portable devices.
• In essence of prior arts literature survey, there is no device disclosed which provide the details of concentration of a solute of interest, so that the cost of purification and separation can be reduced, along with other features.
• Hence, the present patent provides the solution to address the above issues efficiently.

Present invention describes about an integrated microfluidic device for concentrating a dilute solution of a solute based on combining sequentially.

The said device includes following elements as listed in below:

1. First Section contains microchannel consisting of cross junction which establishes contact between two phases and is used for generating slugs/bubbles;
2. Second section channel has a diverging zone followed by a straight section and converging zone. The shear rates are low at a gas-liquid interface ensures that the biomolecules do not denature at the interface;
3. The last section consists of the separator attached to the exit of microchannel where the foam is separated from the aqueous solution allowing continuous operation.

• The nitrogen gas, from the gas cylinder, is sent through the central inlet.
• The liquid solution is pumped using syringe pumps through side inlets.
• The gas-liquid interface is available for adsorption of solute after micro bubbles are formed and adsorption proceeds till bubbles reach the separator.
• The separator separates the foamate & residual phase based on density & collect them separately.