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Nanometer scale sorting filters of high chemical selectivity and high flux are strongly desired for chemical separation1,drug delivery2 and waste water remediation3.In recent years,there has been tremendous interest in the investigation of using CNTs as channels for mass transports4.In this study,a novel process to fabricate stretchable membrane based nanofilters using patterned array of vertically grown carbon nanotubes is proposed.The membrane based nanofilters could stand high pressure which is not reported yet but highly desired for the application of mass transport.Characterization of ion transport by both pressure driven and electric field driven are carried out to ensure the functionality of the CNT membranes.In the test of pressure driven,the transport rate of ions is proportional to the applied pressure.Two molecules,ss-DNA and Haemagglutinin,of different dimensions are used in permeability tests to show that the CNT membranes fabricated could be deployed as sorting nanofilters which enables selective drug delivery by size exclusion.The ss-DNA can pass through CNT membranes by applying electric field and an additional pressure could enhance the permeability.Due to with large dimension,the Haemagglutinin cannot pass CNT membranes just by applying pressure but can pass though by applying pressure and electric field together.Finally,bacterium is involved in the drug delivery to show that the nanofilters could block all micro-scale substance which is preferred for drug purification and separation.Bordetella pertussis is employed for the test and the result shows a perfect blockage of these micro-scale bacteria in the process of drug delivery.