| Industrial production and laboratory synthesis | | | | References |
| On an industrial scale, sodium thiosulfate is produced | | | | ^ a b Holleman, A. F.; Wiberg, E. "Inorganic |
| chiefly from liquid waste products of sodium sulfide | | | | Chemistry" Academic Press: San Diego, 2001. ISBN |
| or sulfur dye manufacture. In the laboratory, this salt | | | | 0-12-352651-5 |
| can be prepared by heating an aqueous solution of | | | | ^ Charles Robert Gibson (1908). The Romance of |
| sodium sulfite with sulfur. | | | | Modern Photography, Its Discovery & Its |
| Principal reactions and applications | | | | Achievements. Seeley & Co. p. 37. |
| Sodium thiosulfate | | | | ^ Aylmore, M. G.; Muir, D. M. "Thiosulfate Leaching of |
| Thiosulfate anion characteristically reacts with dilute | | | | Gold - a Review", Minerals Engineering, 2001, 14, |
| acids to produce sulfur, sulfur dioxide and water: | | | | 135-174 |
| Na2S2O3 + 2HCl 2NaCl + S + SO2 + H2O | | | | ^ "Toxicity, Cyanide: Overview - eMedicine". |
| This reaction is known as a clock reaction, because | | | | Retrieved 2009-01-01. |
| when the sulfur reaches a certain concentration the | | | | ^ Hall AH, Dart R, Bogdan G (June 2007). "Sodium |
| solution turns from colourless to a pale yellow. This | | | | thiosulfate or hydroxocobalamin for the empiric |
| reaction has been employed to generate colloidal | | | | treatment of cyanide poisoning?". Ann Emerg Med 49 |
| sulfur. When the protonation is conducted at low | | | | (6): 80613. doi:10.1016/j.annemergmed.2006.09.021. |
| temperatures, H2S2O3 (thiosulfuric acid) can be | | | | PMID 17098327. |
| obtained. It is a strong acid pKa = 0.6, 1.7. | | | | ^ Cicone JS, Petronis JB, Embert CD, Spector DA |
| Iodometry | | | | (June 2004). "Successful treatment of calciphylaxis |
| In analytical chemistry, the most important use | | | | with intravenous sodium thiosulfate". Am. J. Kidney |
| comes from the fact that the thiosulfate anion | | | | Dis. 43 (6): 11048. doi:10.1053/j.ajkd.2004.03.018. PMID |
| reacts stoichiometrically with iodine, reducing it to | | | | 15168392. |
| iodide as it is oxidized to tetrathionate: | | | | ^ Sodium thiosulfate at Dorland's Medical |
| 2 S2O32(aq) + I2(aq) S4O62(aq) + 2 I(aq) | | | | Dictionaryv d e |
| Due to the quantitative nature of this reaction, as | | | | Sodium compounds |
| well as the fact that Na2S2O35H2O has an excellent | | | | NaAlO2 NaBH3(CN) NaBH4 NaBr NaBrO4 |
| shelf-life, it is used as a titrant in iodometry. | | | | NaCH3COO NaCN NaC6H5CO2 |
| Na2S2O35H2O is also a component of iodine clock | | | | NaC6H4(OH)CO2 NaCl NaClO NaClO2 NaClO3 |
| experiments. | | | | NaClO4 NaF NaH NaHCO3 NaHSO3 NaHSO4 |
| This particular use can be set up to measure the | | | | NaI NaIO3 NaIO4 NaMnO4 NaNH2 NaNO2 |
| oxygen content of water through a long series of | | | | NaNO3 NaN3 NaOH NaO2 NaPO2H2 |
| reactions. It is also used in estimating volumetrically, | | | | NaReO4 NaSCN NaSH NaTcO4 NaVO3 |
| the concentrations of certain compounds in solution | | | | Na2CO3 Na2C2O4 Na2CrO4 Na2Cr2O7 |
| (hydrogen peroxide, for instance), and in estimating | | | | Na2MnO4 Na2MoO4 Na2O Na2O2 |
| the chlorine content in commercial bleaching powder | | | | Na2O(UO3)2 Na2S Na2SO3 Na2SO4 Na2S2O3 |
| and water. | | | | Na2S2O4 Na2S2O5 Na2S2O6 Na2S2O7 |
| Photographic processing | | | | Na2S2O8 Na2SeO3 Na2SeO4 Na2SiO3 Na2Te |
| The terminal sulfur atom in S2O32 binds to soft | | | | Na2TeO3 Na2Ti3O7 Na2U2O7 NaWO4 |
| metals with high affinity. Thus, silver halides, e.g. AgBr, | | | | Na2Zn(OH)4 Na3N Na3P Na3VO4 Na4Fe(CN)6 |
| typical components of photographic emulsions, | | | | Na5P3O10v d e |
| dissolve upon treatment with aqueous thiosulfate: | | | | Antifungals (D01 and J02) |
| 2 S2O32 + AgBr [Ag(S2O3)2]3 + Br- | | | | Wall/membrane |
| In this application to photographic processing, | | | | Ergosterolinhibitors |
| discovered by John Herschel and used for both film | | | | Azoles |
| and photographic paper processing, the sodium | | | | (lanosterol 14alpha-demethylase inhibitors) |
| thiosulfate is known as a photographic fixer, and is | | | | Imidazolestopical: Bifonazole, Clomidazole, |
| often referred to as hypo, from the original chemical | | | | Clotrimazole#, Croconazole, Econazole, Fenticonazole, |
| name, hyposulphite of soda. | | | | Ketoconazole, Isoconazole, Miconazole#, Neticonazole, |
| Gold extraction | | | | Oxiconazole, Sertaconazole, Sulconazole, Tioconazole |
| Sodium thiosulfate is one component of an | | | | Triazolestopical: (Fluconazole#, |
| alternative lixiviant to cyanide for extraction of gold. | | | | Fosfluconazole)systemic: (Fluconazole, Itraconazole, |
| It forms a strong complex with gold(I) ions, | | | | Posaconazole, Voriconazole) |
| [Au(S2O3)2]3-. The advantage of this approach is | | | | Benzimidazolestopical: Thiabendazole |
| that thiosulfate is essentially non-toxic and that ore | | | | Polyene antimycotics |
| types that are refractory to gold cyanidation (e.g. | | | | (ergosterol binding)topical: (Natamycin, |
| carbonaceous or Carlin type ores) can be leached by | | | | Nystatin#)systemic: (Amphotericin B#) |
| thiosulfate. Some problems with this alternative | | | | Allylamines |
| process include the high consumption of thiosulfate, | | | | (squalene monooxygenaseinhibitors)topical: |
| and the lack of a suitable recovery technique, since | | | | (Amorolfine, Butenafine, Naftifine, |
| [Au(S2O3)2]3- does not adsorb to activated carbon, | | | | Terbinafine)systemic: (Terbinafine) |
| which is the standard technique used in gold | | | | -glucan synthaseinhibitorsechinocandins (Anidulafungin, |
| cyanidation to separate the gold complex from the | | | | Caspofungin, Micafungin) |
| ore slurry. | | | | Intracellular |
| Analytical chemistry | | | | Pyrimidine analogues/ |
| Sodium thiosulfate is also used in analytical chemistry. | | | | Thymidylate synthase inhibitors |
| It can, when heated with a sample containing | | | | Flucytosine# |
| aluminum cation, produce a white precipitation: | | | | Mitotic inhibitors |
| 2Al3+ + 3S2O32- + 3H2O 3SO2 + 3S + 2Al(OH)3 | | | | Griseofulvin# |
| Medical | | | | Others |
| It is used as an antidote to cyanide poisoning. | | | | Bromochlorosalicylanilide Methylrosaniline |
| Thiosulfate acts as a sulfur donor for the conversion | | | | Tribromometacresol Undecylenic acid Polynoxylin |
| for cyanide to thiocyanate (which can then be safely | | | | Chlorophetanol Chlorphenesin Ticlatone |
| excreted in the urine), catalyzed by the enzyme | | | | Sulbentine Ethyl hydroxybenzoate Haloprogin |
| rhodanase. | | | | Salicylic acid Selenium sulfide# Ciclopirox |
| It has also been used as treatment of calciphylaxis in | | | | Amorolfine Dimazole Tolnaftate Tolciclate |
| hemodialysis patients with end-stage renal disease.in | | | | Sodium thiosulfate# Whitfield's ointment# |
| foot baths for prophylaxis of ringworm, and as a | | | | Potassium iodide# |
| topical antifungal agent for tinea versicolor.in | | | | Tea tree oil citronella oil lemon grass orange oil |
| measuring the volume of extracellular body fluid and | | | | patchouli lemon myrtle |
| the renal glomerular filtration rate. | | | | PCP: Pentamidine Dapsone Atovaquone |
| Other uses | | | | #WHO-EM. Withdrawn from market. CLINICAL |
| Sodium thiosulfate is also used: | | | | TRIALS: hase III. Never to phase IIIsee also |
| As a component in hand warmers and other chemical | | | | diseasesv d e |
| heating pads that produce heat by exothermic | | | | Antidotes (V03AB) |
| crystallization of a supercooled solution. | | | | Nervous system |
| In Bleach | | | | Nerve agent / Organophosphate poisoning |
| In pH testing of bleach substances. The universal | | | | Atropine# Biperiden Diazepam# Oximes |
| indicator and any other liquid pH indicator are | | | | (Pralidoxime, Obidoxime) see also Cholinesterase |
| destroyed by bleach, rendering them useless for | | | | Opioid overdose |
| testing the pH. If one first adds sodium thiosulfate to | | | | Diprenorphine Doxapram Nalorphine Naloxone# |
| such solutions, it will neutralize the color-removing | | | | Naltrexone Nalmefene |
| effects of bleach and allow one to test the pH of | | | | Barbiturate overdose |
| bleach solutions with liquid indicators. The relevant | | | | Bemegride Ethamivan |
| reaction is akin to the iodine reaction: thiosulfate | | | | Benzodiazepine overdose |
| reduces the hypochlorite (active ingredient in bleach) | | | | Cyprodenate Flumazenil |
| and in so doing becomes oxidized to sulfate. The | | | | GHB overdose |
| complete reaction is: | | | | Physostigmine SCH-50911 |
| 4 NaClO + Na2S2O3 + 2 NaOH 4 NaCl + 2 Na2SO4 + | | | | Reversal of neuromuscular blockade |
| H2O | | | | Sugammadex |
| To dechlorinate tap water for aquariums or treat | | | | Cardiovascular |
| effluent from waste water treatments prior to | | | | Heparin |
| release into rivers. The reduction reaction is analogous | | | | Protamine# |
| to the iodine reduction reaction. Treatment of tap | | | | Digoxin toxicity |
| water requires between 0.1 grams and 0.3 grams of | | | | Digoxin Immune Fab |
| pentahydrated (crystalline) sodium thiosulfate per 10 | | | | Beta blocker |
| liters of water. | | | | Glucagon |
| To lower chlorine levels in swimming pools and spas | | | | Other |
| following super chlorination. | | | | Methanol / Ethylene glycol poisoning |
| To remove iodine stains, e.g. after the explosion of | | | | Ethanol Fomepizole |
| nitrogen triiodide. | | | | Paracetamol toxicity (Acetaminophen) |
| In bacteriological water assessment. | | | | Acetylcysteine# Glutathione Methionine# |
| In the tanning of leather. | | | | Arsenic poisoning |
| To demonstrate the concept of reaction rate in | | | | Dimercaprol# Succimer |
| chemistry classes. The thiosulfate ion can decompose | | | | Cyanide poisoningnitrite (Amyl nitrite, Sodium |
| into the sulfite ion and a colloidal suspension of sulfur, | | | | nitrite#) Sodium thiosulfate# |
| which is opaque. The equation for this acid-catalysed | | | | 4-Dimethylaminophenol Hydroxocobalamin |
| reaction is as follows: | | | | Toxic metals (cadmium, mercury, lead, thallium) |
| S2O32(aq) SO32(aq) + S(s) | | | | Edetates Dimercaprol# Prussian blue |
| To demonstrate the concept of supercooling in | | | | Hydrofluoric acid |
| physics classes. Melted sodium thiosulfate is very | | | | Calcium gluconate# |
| easy to overcool to room temperature and when | | | | Other |
| crystallization is forced, the sudden temperature jump | | | | Prednisolone and promethazine oxidizing agent |
| to 48.3C can be experienced by touch. | | | | (potassium permanganate) iodine-131 (Potassium |
| As part of patina recipes for copper alloys. | | | | iodide) Methylthioninium chloride# |
| Often used in pharmaceutical preparations as an | | | | Emetic |
| anionic surfactant to aid in dispersion. | | | | Ipecacuanha (Syrup of ipecac) Copper sulfate |
| It can also be used as a very interesting solute in | | | | #WHO-EM. Withdrawn from market. CLINICAL |
| supersaturation experiments. | | | | TRIALS: hase III. |