Editing Phenothiazine (section)

=== Nondrug applications ===
The synthetic dye [[methylene blue]], containing the structure, was described in 1876. Many water-soluble phenothiazine derivatives, such as [[methylene blue]], [[methylene green]], [[thionine]], and others, can be [[electropolymerization|electropolymerized]] into [[conductive polymers]] used as [[electrocatalyst]]s for NADH oxidation in enzymatic biosensors and biofuel cells.<ref>{{cite journal | doi=10.1016/0003-2670(94)85016-X | volume=285 | issue=1–2 | title=Electrocatalytic oxidation of reduced nicotinamide coenzymes at Methylene Green-modified electrodes and fabrication of amperometric alcohol biosensors | journal=Analytica Chimica Acta | pages=125–133| date=1994-01-20 | last1=Chi | first1=Qijin | last2=Dong | first2=Shaojun | bibcode=1994AcAC..285..125C }}</ref><ref>{{cite journal | doi = 10.1002/(SICI)1521-4109(199906)11:8<553::AID-ELAN553>3.0.CO;2-6 | volume=11 | issue=8 | title=Electropolymerized Azines: Part II. In a Search of the Best Electrocatalyst of NADH Oxidation | journal=Electroanalysis | pages=553–557| year=1999 | last1=Karyakin | first1=Arkady A. | last2=Karyakina | first2=Elena E. | last3=Schuhmann | first3=Wolfgang | last4=Schmidt | first4=Hanns-Ludwig }}</ref><ref>{{cite journal | doi=10.1016/j.bios.2008.07.043 | pmid=18774285 | volume=24 | issue=4 | title=Citric acid cycle biomimic on a carbon electrode | journal=Biosensors and Bioelectronics | pages=939–944| date=December 2008 | last1=Sokic-Lazic | first1=Daria | last2=Minteer | first2=Shelley D. }}</ref>

Phenothiazine is used as an anaerobic inhibitor for [[acrylic acid]] polymerization, often used as an in-process inhibitor during the purification of acrylic acid.<ref>{{Cite journal|title=Inhibition of acrylic acid polymerization by phenothiazine and p-methoxyphenol. II. Catalytic inhibition by phenothiazine|journal = Journal of Polymer Science Part A: Polymer Chemistry|volume = 30|issue = 4|pages = 569–576|last=Levy|first=Leon B.|date=1992-03-30|language=en|doi=10.1002/pola.1992.080300407|bibcode = 1992JPoSA..30..569L}}</ref>