亚甲基蓝的制备及用途
2020-03-18
亚甲蓝（化学式：C₈H₈ClN₃S，分子量：319.86），3,7-双（二甲基氨基）吩噻嗪-5-氯化铵，是一种吩噻嗪盐，其正电荷不稳定。外观为深绿色的青铜光泽晶体（三水合物），熔点为215ºC，闪点为14℃，密度为1g/mL。溶于水/乙醇，不溶于乙醚。亚甲基蓝在空气中相对稳定，其水溶液呈碱性且有毒。亚甲蓝广泛用于化学指示剂，染料，生物污渍和药物。
制备：
1.用N，N-二甲基苯胺进行亚硝化，还原为对氨基二甲基苯胺，再用重铬酸钠和硫代硫酸钠氧化，硫化和缩合，然后用氯化锌形成盐，将盐析出，过滤并干燥，得到成品。
2.将100千克纯水添加到10千克工业次甲基蓝（碱性湖蓝色BB）中，并在搅拌的同时用蒸汽加热至80-90°C以使其溶解。然后在30分钟内缓慢添加7.5kg的20％碳酸钠热溶液，并继续搅拌10min。静置半小时后，在不超过90°C的温度下加热溶液，趁热过滤，然后向澄清的滤液中加入3kg的1：1盐酸，均匀搅拌后，冷却晶体。晶体完全溶解后，将其离心干燥，并在40-50°C下干燥，以获得最终产品。
用途：
染色：
可用于制造墨水和色淀，以及对生物和细菌组织进行染色。 [1]与ZnCl2混合后，可用于棉，亚麻，丝织物，纸，竹和木材的染色。 [1]而且，可以将其与结晶紫和黄色糊精以78：13：9的比例混合以形成碱性宝蓝色。
医疗
Methylene blue is used to treat methaemoglobinemia because of its reducing properties. It is also used to rescue nitrobenzene, nitrite and cyanide poisoning. For patients with mild carbon monoxide poisoning, methylene blue can be injected intravenously for detoxification. Clinically used to treat sulfa allergy.
Because of its bactericidal effect, oral methylene blue or rinsing with its solution can treat cystitis and urethritis. In addition, methylene blue is excreted from the urine within 30 minutes (injection) to several hours (oral) after entering the human body, causing the urine to temporarily become blue, so it is also used for renal function measurement.
In ornamental fish culture, 0.1-0.2ppm methylene blue solution is also used for disinfection or treatment of diseases such as white spot disease.
Analysis and identification:
In chemical experiments, analytically pure methylene blue can be used as an adsorption indicator in chemical reagents. It can also be used to precipitate perchlorate and osmate, and to catalytically determine selenium and molybdenum.
At the same time, methylene blue is also oxidizing, and can oxidize some highly reducing substances, such as glucose or zinc, which is itself reduced to a colorless reduced methylene blue (some people call it methylene white). After being reduced, the reduced methylene blue has a certain reducing ability, and can be oxidized by some oxidizing substances, such as oxygen in the air, to generate blue methylene blue in the oxidation state. Therefore, methylene blue can be used for oxidation-reduction titration and can also be used to demonstrate the oxidation-reduction oscillation reaction. The most typical one is the blue bottle experiment.
制备：
1.用N，N-二甲基苯胺进行亚硝化，还原为对氨基二甲基苯胺，再用重铬酸钠和硫代硫酸钠氧化，硫化和缩合，然后用氯化锌形成盐，将盐析出，过滤并干燥，得到成品。
2.将100千克纯水添加到10千克工业次甲基蓝（碱性湖蓝色BB）中，并在搅拌的同时用蒸汽加热至80-90°C以使其溶解。然后在30分钟内缓慢添加7.5kg的20％碳酸钠热溶液，并继续搅拌10min。静置半小时后，在不超过90°C的温度下加热溶液，趁热过滤，然后向澄清的滤液中加入3kg的1：1盐酸，均匀搅拌后，冷却晶体。晶体完全溶解后，将其离心干燥，并在40-50°C下干燥，以获得最终产品。
用途：
染色：
可用于制造墨水和色淀，以及对生物和细菌组织进行染色。 [1]与ZnCl2混合后，可用于棉，亚麻，丝织物，纸，竹和木材的染色。 [1]而且，可以将其与结晶紫和黄色糊精以78：13：9的比例混合以形成碱性宝蓝色。
医疗
Methylene blue is used to treat methaemoglobinemia because of its reducing properties. It is also used to rescue nitrobenzene, nitrite and cyanide poisoning. For patients with mild carbon monoxide poisoning, methylene blue can be injected intravenously for detoxification. Clinically used to treat sulfa allergy.
Because of its bactericidal effect, oral methylene blue or rinsing with its solution can treat cystitis and urethritis. In addition, methylene blue is excreted from the urine within 30 minutes (injection) to several hours (oral) after entering the human body, causing the urine to temporarily become blue, so it is also used for renal function measurement.
In ornamental fish culture, 0.1-0.2ppm methylene blue solution is also used for disinfection or treatment of diseases such as white spot disease.
Analysis and identification:
In chemical experiments, analytically pure methylene blue can be used as an adsorption indicator in chemical reagents. It can also be used to precipitate perchlorate and osmate, and to catalytically determine selenium and molybdenum.
At the same time, methylene blue is also oxidizing, and can oxidize some highly reducing substances, such as glucose or zinc, which is itself reduced to a colorless reduced methylene blue (some people call it methylene white). After being reduced, the reduced methylene blue has a certain reducing ability, and can be oxidized by some oxidizing substances, such as oxygen in the air, to generate blue methylene blue in the oxidation state. Therefore, methylene blue can be used for oxidation-reduction titration and can also be used to demonstrate the oxidation-reduction oscillation reaction. The most typical one is the blue bottle experiment.
