▎ 摘　　要

NOVELTY - Electrochemical comprises (a) a sensing element comprising many first antisense oligonucleotides, the sequence of which is complementary to a first nucleic acid sequence in a target gene of the biological pathogen, (b) a first electrode connected to a first end of each of the many antisense oligonucleotides, and (c) a second electrode electrically connected to the first electrode, where contact of the sample with the first electrode causes binding of the first antisense oligonucleotides to the first nucleic acid sequence in the target gene, to provide a signal to identify presence of the biological pathogen. USE - The electrochemical biosensor is useful for detecting biological pathogen in a sample (claimed), where the pathogen is e.g. coronavirus disease-19, severe acute respiratory syndrome Ebola, Bird Flu, Streptococcus, adenovirus, herpes, gonorrhea, syphilis, and Chlamydia. ADVANTAGE - The electrochemical biosensor rapidly, selectively, and efficiently identify and detect biological pathogens in samples. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) detecting a biological pathogen in a sample, comprising (aa) providing many first antisense oligonucleotides having a sequence complementary to a first nucleic acid sequence in a target gene of the biological pathogen, (bb) providing a first electrode and a second electrode electrically connected to one another, (cc) connecting a first end of the first antisense oligonucleotides to the first electrode, (dd) contacting the first electrode to the sample, and (ee) measuring a signal from the first and second electrodes, where the binding of the target gene of the biological pathogen to the first antisense oligonucleotides provides the signal identifying the presence of the biological pathogen in the sample; and (2) selecting at least one antisense oligonucleotide probe for detecting a biological pathogen, comprising (ab) identifying a target gene in the biological pathogen, (ac) obtaining the nucleic acid sequence of the target gene, (ad) producing a library of antisense oligonucleotides of 20 nucleotides, where the sequence of each antisense oligonucleotide is complementary to a section of the nucleic acid sequence in the target gene and where guanine and cysteine form 40-60% of each antisense oligonucleotide in the library and none of the antisense oligonucleotides in the library are complementary to a section of the target gene with the sequence gggg, the average unpaired probability of each of the antisense oligonucleotides in the library is at least 0.5, ranking the antisense oligonucleotides in the library in descending order of average unpaired probability, and selecting the antisense oligonucleotide probe from the antisense oligonucleotides in the library.