Thread-based oxygen sensor

An apparatus comprising an oxygen sensor for sensing dissolved oxygen concentration in tissue in a wound bed, said oxygen sensor comprising an electrochemical sensor configured for measuring an oxygenation level in said wound bed, said electrochemical sensor comprising a cathode and an anode, wherein said cathode comprises a first conductive thread, wherein said anode comprises a second conductive thread, wherein said first and second conductive threads have proximal sections connected to a potentiostat, wherein said second conductive thread has a bare distal section and a shielded section that extends between said proximal section and said bare distal section, wherein one or more of said threads comprises gold, and wherein said electrochemical sensor has an adjustable sensing zone.