Methylene blue powder, also known as methylene blue, is a phenothiazine salt with the chemical formula C16H18N3ClS and CAS 101-72-4. It is a shiny dark green bronze crystal or powder, soluble in water and ethanol, insoluble in ether. It is relatively stable in the air, and its aqueous solution is alkaline and toxic. It is widely used in chemical indicators (methylene blue indicators), dyes, biological dyes and drugs.
After adding the solvent into the methylene blue solution, adding dilute sulfuric acid will make the solution fade. It can be recovered if ammonia is quickly added or exposed in the air. In chemical experiments, the analytical can be used as the sample for determination, as the adsorption indicator in chemical reagents, as well as for precipitation of perchlorate and rhenium, and Catalytic Spectrophotometric Determination of selenium and molybdenum. At the same time, it is also oxidizing. It can oxidize some substances with strong reducibility and be reduced to colorless reduced methylene blue (some people call it methylene white). it has certain reducibility and can be oxidized by some oxidizing substances, such as oxygen in the air, to produce oxidized blue methylene blue. Therefore, it can be used for oxidation-reduction titration and demonstration of oxidation-reduction oscillating reaction.
|
|
|
Methylene blue powder is widely used in chemical indicators, dyes, biological dyes, and pharmaceuticals. Especially in the dyeing industry, used for manufacturing ink, etc. It is also widely used in the following fields.
1. Industrial sector
Belonging to the dye class compounds, industrial grade methylene blue is often used for dyeing cotton, silk, paper, etc. It can also be applied in coloring bamboo and wood, as well as manufacturing inks, color lakes, etc. In addition, it is often used as a bacterial stain, indicator, etc.
2. Pharmaceutical field
It has been applied in the field of medicine for a long time. Due to its redox properties, it can be used to relieve cyanide, nitrite, aniline, acetanilide poisoning, or methemoglobinemia caused by sulfonamide drugs.
In recent years, scholars have also studied the application of it and its metabolites in various bacterial and viral infections, cancer, and central nervous system diseases such as depression, schizophrenia, Alzheimer's disease, and others.
3. Aquaculture field
In aquaculture, it can be used as a disinfectant. The principle is that the ionic compounds formed in the aqueous solution can compete with the microbial enzyme system for hydrogen ions, causing enzyme inactivation and ultimately leading to the loss of microbial survival ability; It also has certain therapeutic effects in treating fish diseases such as small melon worm disease, oblique tube worm disease, red mouthed disease, water mold disease, and shrimp larvae sticky disease. It can also be used as an antifungal drug to reduce mortality rates during fish transportation.
4. Skin care field
There are studies indicating that there is also potential in skin care. It can eliminate free radicals, stimulate cell proliferation in young and old dermal fibroblasts, thereby improving skin vitality, promoting skin elasticity and collagen synthesis, and protecting the skin matrix through degradation by matrix metalloproteinases. Therefore, it can become a promising agent in anti-aging cosmetics.
5. Chromogenic reagent
After acidification, heating, nitrogen blowing, or distillation of sulfides in the sample, the generated hydrogen sulfide is absorbed by sodium hydroxide solution. The generated sulfur ions react with N, N-dimethyl-phenylenediamine in an acidic solution of ammonium iron sulfate to generate methylene blue. The absorbance is measured at 665nm wavelength, and the sulfide content is proportional to the absorbance value.
This is our advanced product Methylene Blue Powder.
#1: We are a chemical researching agency & factory, we make a living on Chemistry, professional service, the best price in the best quality.
#2: We are Pursuing the best chemical technology, we insist the quality no matter how fierce competition.
#3: We don't do anything shame on Great Chemistry! Don't trust the unreasonable price, please compare the price in the same level quality!
Methylene blue, as a type of phenothiazine compound, has attracted much attention for its unique redox properties and wide application fields (such as dyeing, biological dyeing, pharmaceuticals, chemical analysis, etc.), and its synthesis method is highly regarded. The common synthesis methods are systematically explained from five dimensions: traditional synthesis method, improved synthesis method, phenothiazine raw material synthesis method, industrial grade synthesis method, and special form synthesis method.
Traditional synthesis method: N, N-dimethylaniline route
The traditional synthesis method uses N, N-dimethylaniline as the starting material to prepare methylene blue through steps such as nitrosation, reduction, oxidation, sulfurization, condensation, and salt formation. The specific process is as follows:
Nitrification reaction: Reacting N, N-dimethylaniline with sodium nitrite under acidic conditions (such as sulfuric acid) to produce nitroso-N, N-dimethylaniline. This step requires strict control of temperature (0-5 ℃) and pH value (acidic environment) to prevent side reactions from occurring.
Reduction reaction: Nitroso compounds are reduced to para aminodimethylaniline under the action of a reducing agent (such as iron powder). The reduction reaction needs to be carried out under inert gas protection to avoid oxidation.
Oxidation, sulfidation, and condensation reactions: Reacting para aminodimethylaniline with sodium dichromate (oxidant) and sodium thiosulfate (sulfidizer) under acidic conditions to produce phenothiazine derivatives. This step requires precise control of the reactant ratio and reaction time to ensure the completeness of the condensation reaction.
Salting reaction: Phenothiazine derivatives are salted with zinc chloride under alkaline conditions to produce methylene blue. The salt formation reaction needs to be carried out at low temperatures to prevent product decomposition.
Post processing: Pure methylene blue is obtained through steps such as salt precipitation, filtration, washing, and drying.
Raw material consumption (based on producing 1 ton of methylene blue):
N. N-Dimethylaniline:
790kg
Sodium nitrite:
250kg
Sulfuric acid:
760kg
Hydrochloric acid (31%):
500kg
Sodium dichromate (95%):
1400kg
Sodium thiosulfate:
830kg
Zinc chloride:
372kg
Iron powder:
650kg
Advantages: Easy to obtain raw materials, mature technology, suitable for large-scale production.
Disadvantages: Multiple reaction steps, long cycle, requiring the use of large amounts of strong acids and heavy metal salts, and high environmental pollution risk.
Improved synthesis method: optimizing reaction conditions and raw material ratios
In response to the shortcomings of traditional synthesis methods, researchers have improved the yield and purity of methylene blue by optimizing reaction conditions (such as temperature, pH value, reaction time) and raw material ratios. For example:
Temperature control: In the nitrosation reaction, controlling the temperature between 0-5 ℃ can reduce the occurrence of side reactions and improve the purity of nitroso compounds.
PH adjustment: In oxidation, sulfurization, and condensation reactions, adjusting the pH value (such as maintaining it under acidic or alkaline conditions) can promote the progress of the reaction and improve product yield.
Optimization of raw material ratio: By adjusting the ratio of sodium dichromate to sodium thiosulfate, the balance of oxidation, sulfurization, and condensation reactions can be optimized, reducing the residue of unreacted raw materials.
Case: A study improved the yield of methylene blue from 60% in traditional methods to 85% by optimizing reaction conditions, while reducing the use of heavy metal salts and minimizing environmental pollution.
Advantages: High yield, good purity, and minimal environmental pollution.
Disadvantages: It requires precise control of reaction conditions and high equipment requirements.
Synthesis method of phenothiazine raw materials: direct use of phenothiazine derivatives
The raw material synthesis method of phenothiazine uses phenothiazine or its derivatives as raw materials, and directly synthesizes methylene blue through nitration, reduction, aminomethylation, and oxidation reactions. The specific process is as follows:
Nitrification reaction:
Reacting phenothiazine with a mixed acid of concentrated nitric acid and concentrated sulfuric acid to produce nitrophenothiazine.
Reduction reaction:
Nitrophenothiazine is reduced to aminophenothiazine by a reducing agent (such as iron powder).
Aminomethylation reaction:
Aminophenothiazine is reacted with formaldehyde and formic acid to produce aminomethylphenothiazine.
Oxidation reaction:
Aminomethylphenothiazine is oxidized by an oxidant (such as sodium dichromate) to produce methylene blue powder.
Advantages:
Easy availability of raw materials, fewer reaction steps, and shorter production cycle.
Disadvantages:
Nitrification reaction requires a large amount of concentrated acid, which is highly corrosive to equipment; The oxidation reaction requires precise control of the amount of oxidant to prevent excessive oxidation.
Industrial grade synthesis method: alkaline lake blue BB purification method
Industrial grade synthesis method uses industrial methylene blue (alkaline lake blue BB) as raw material, and purifies methylene blue through dissolution, filtration, crystallization, and drying steps. The specific process is as follows:
Dissolve:
Add industrial methylene blue to pure water, stir while heating with steam to 80-90 ℃ to dissolve it.
Filtration:
Filter the solution while it is hot to remove insoluble impurities.
Crystallization:
Add hydrochloric acid to the clear filtrate, stir evenly, and then cool to crystallize.
Drying:
Centrifuge and spin dry the fully crystallized product, and dry it at 40-50 ℃ to obtain the finished product.
Advantages:
Simple process, low cost, suitable for industrial production.
Disadvantage:
The purity of the product is greatly affected by the raw materials, and the quality of the raw materials needs to be strictly controlled.
Special Form Synthesis Method: Preparation of Methylene Blue Crystals and Composite Films
To meet specific application requirements such as drug release and photocatalysis, researchers have developed a method for preparing methylene blue crystals and composite films.
Preparation of methylene blue crystals:
Hydrothermal reaction method: Dissolve calcium nitrate and diammonium hydrogen phosphate separately in deionized water to prepare solutions A and B. Add methylene blue to solution B and add solution A dropwise to the continuously stirred solution B. After the dropwise addition is completed, the hydrothermal reaction is carried out under stirring conditions for 4 hours, and then left to stand for 12 hours for aging. Finally, the reaction solution was sieved, washed, and dried to obtain rod-shaped methylene blue crystals.
Advantages: Controllable crystal size and shape, suitable for drug release and photocatalytic applications.
Disadvantages: The process is complex and requires precise control of reaction conditions.
Preparation of methylene blue bovine serum albumin composite membrane:
Self casting membrane method: Prepare methylene blue solution and bovine serum albumin solution separately with buffer solution. Mix the two, manually shake vigorously at room temperature, transfer to a container with ITO conductive glass on the bottom, dry to remove the solvent, and prepare a methylene blue bovine serum albumin composite film.
Advantages: Simple operation, low cost, good biocompatibility, suitable for the application of photocathode reaction media.
Disadvantages: The performance of composite films is greatly affected by the proportion of raw materials and preparation conditions.
Hot Tags: methylene blue powder cas 61-73-4, suppliers, manufacturers, factory, wholesale, buy, price, bulk, for sale, p Dimethylaminobenzaldehyde, p Naphtholbenzein, 4 5 Chloro 2 pyridylazo 1 3 phenylenediamine, Laboratory Reagent, Indicator Reagent, naphtholbenzein indicator