of bio molecules of the present invention can be applied to various bio chips or biosensors including but not limited to blood glucose meters lipid meters and micro array bio chips with reference to fig3 and 4 for a flow chart and a schematic view of a method of modifying the surface of bio molecules in accordance with the second preferred embodiment of the present invention respectively the method of modifying the surface of bio molecules comprises the following steps s 21 provide a bio molecule combined with at least one first ssdna wherein first free energy u03b4g1 exists between the first ssdna and the bio molecule s 22 add a second ssdna as a recovery dna wherein a second free energy u03b4g2 exists between the second ssdna and the first ssdna and the second free energy is smaller than the first free energy s 23 separate the first ssdna from the bio molecule and combine the first ssdna with the second ssdna through the thermodynamic principle in an example of this preferred embodiment the bio molecule 21 is one selected from the collection of deoxyribonucleic acid enzyme antigen and any bio molecule applied in a biosensor or a bio chip and this embodiment of the present invention uses the ssdna as the dna probe wherein the dna probe has a length of 18 to 3000 bases and preferably 500 to 2500 bases but the invention is not limited to such length only in an example of this preferred embodiment this embodiment uses 21 bases as an example and prevents the ssdna from producing a first ssdna 22 and a second ssdna 23 having a length of 12 to 40 bases and preferably 15 to 35 bases wherein the first ssdna 22 of the sequence identification number 2.