A microfluidic device, comprising: a first layer of a single type of gas permeable material that defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, said fluid comprising a fluid from the group consisting of: blood, an organic solvent or an aqueous solution; the first layer has an alternating occurrence of the chambers for gas flow and the chambers for fluid flow; a second layer of a single type of gas permeable material stacked upon the first layer, where the second layer defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, the second layer has an alternating occurrence of the chambers for gas flow and the chambers for fluid flow in reverse order to the occurrence of the chambers for gas flow and the chambers for fluid flow of the first layer; a third layer of a single type of gas permeable material stacked upon the second layer, where the third layer defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, the third layer has an alternating occurrence of the chambers for gas flow and the chambers for fluid flow in reverse order to the occurrence of the chambers for gas flow and the chambers for fluid flow of the second layer, wherein the thickness of the gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is between 1 μm and 100μm, wherein any chamber for gas flow and any chamber for fluid flow are arranged such that flow directions for the gas and the fluid are parallel or anti-parallel to one another, wherein each chamber for fluid flow is located between two chambers for gas flow, wherein any chambers for fluid flow in the first layer are positioned between two chambers for gas flow in the same layer, and said chambers for fluid flow are aligned vertically with a chamber for gas flow in any adjacent layer, and wherein with respect to the chambers for fluid flow and the chambers for gas flow, only the chambers for fluid flow are coated with a biological molecule or an anti-coagulant; or comprise a three-dimensional structure to induce fluid mixing. a first layer of a single type of gas permeable material that defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, said fluid comprising a fluid from the group consisting of: blood, an organic solvent or an aqueous solution; the first layer has an alternating occurrence of the chambers for gas flow and the chambers for fluid flow; a second layer of a single type of gas permeable material stacked upon the first layer, where the second layer defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, the second layer has an alternating occurrence of the chambers for gas flow and the chambers for fluid flow in reverse order to the occurrence of the chambers for gas flow and the chambers for fluid flow of the first layer; a third layer of a single type of gas permeable material stacked upon the second layer, where the third layer defines therein a plurality of chambers for gas flow and a plurality of chambers for fluid flow, the third layer has an alternating occurrence of the chambers for gas flow and the chambers for fluid flow in reverse order to the occurrence of the chambers for gas flow and the chambers for fluid flow of the second layer, wherein the thickness of the gas permeable material separating any chamber for gas flow from an adjacent chamber for fluid flow is between 1 μm and 100μm, wherein any chamber for gas flow and any chamber for fluid flow are arranged such that flow directions for the gas and the fluid are parallel or anti-parallel to one another, wherein each chamber for fluid flow is located between two chambers for gas flow, wherein any chambers for fluid flow in the first layer are positioned between two chambers for gas flow in the same layer, and said chambers for fluid flow are aligned vertically with a chamber for gas flow in any adjacent layer, and wherein with respect to the chambers for fluid flow and the chambers for gas flow, only the chambers for fluid flow are coated with a biological molecule or an anti-coagulant; or comprise a three-dimensional structure to induce fluid mixing.