A biomimetic microfluidic system comprising: a substrate ; a first channel formed in the substrate that extends from a first input to a first output along a longitudinal direction of the substrate, the first channel having a longitudinal dimension and a first transverse dimension ; a second channel formed in the substrate that extends from a second input to a second output along the longitudinal direction of the substrate, wherein the second channel has the longitudinal dimension and a second transverse dimension, and the first and second channels extend substantially parallel; a series of columns between the first channel and the second channel; a series of gaps between the columns, the gaps extending from the first channel to the second channel to create a fluid communication path passing between the columns, and dimensioned longitudinally between 0.1 micrometers and 20 micrometers to selectively capture a biological source material capable of producing blood platelets; a first source connected to the first input, the first source configured to selectively introduce into the first channel at least one first biological composition comprising the biological source material at a first channel flow rate; and a second source connected to the second input, the second source configured to selectively introduce into the second channel at least one second biological composition at a second channel flow rate, wherein the first source and the second source are configured to control the first channel flow rate and the second channel flow rate, respectively, to create a differential between the channels that is configured to generate physiological shear rates along the second channel bounded within a predetermined range between 100 s -1 and 10,000 s -1 and influence the flow within the first channel through the series of gaps to produce the blood platelets. a substrate ; a first channel formed in the substrate that extends from a first input to a first output along a longitudinal direction of the substrate, the first channel having a longitudinal dimension and a first transverse dimension ; a second channel formed in the substrate that extends from a second input to a second output along the longitudinal direction of the substrate, wherein the second channel has the longitudinal dimension and a second transverse dimension, and the first and second channels extend substantially parallel; a series of columns between the first channel and the second channel; a series of gaps between the columns, the gaps extending from the first channel to the second channel to create a fluid communication path passing between the columns, and dimensioned longitudinally between 0.1 micrometers and 20 micrometers to selectively capture a biological source material capable of producing blood platelets; a first source connected to the first input, the first source configured to selectively introduce into the first channel at least one first biological composition comprising the biological source material at a first channel flow rate; and a second source connected to the second input, the second source configured to selectively introduce into the second channel at least one second biological composition at a second channel flow rate, wherein the first source and the second source are configured to control the first channel flow rate and the second channel flow rate, respectively, to create a differential between the channels that is configured to generate physiological shear rates along the second channel bounded within a predetermined range between 100 s -1 and 10,000 s -1 and influence the flow within the first channel through the series of gaps to produce the blood platelets. <EOS>