Luminol, also known as luminescent ammonia, chemical name is 3-aminobenzoylhydrazide. It is a kind of chemical used to detect blood stains at the scene of the crime, which can make the scene unable to observe the blood stains with naked eyes. But how to use luminol to produce a reaction, this problem should have many people do not understand, the following will introduce how luminol luminescence.
What is the luminol reaction
Luminol reaction is a classical chemiluminescence reaction, which is different from fluorescence. The source of luminescence is the excited state intermediate produced in the chemical reaction, which releases blue light when it returns to the ground state. Luminol can react with hydrogen peroxide and other oxidants in alkaline environment to obtain luminescent intermediates. This reaction usually requires the catalysis of transition metal salts, such as iron, copper or cobalt.
Luminol luminescent principle:
Luminol reacts with hydroxide to form a double negative ion, which can be oxidized by oxygen decomposed by hydrogen peroxide to form an organic peroxide. The peroxide is very unstable and immediately decomposes into nitrogen (after luminol is oxidized by organic oxidants such as dimethyl sulfoxide, it does not generate nitrogen, but nitrogen-containing organic compounds), and forms excited 3-aminophthalic acid. During the transition from excited state to ground state, the released energy exists in the form of photons, and the wavelength is located in the blue part of visible light.
How luminol reacts:
First of all, we need to prepare the mixed solution of basic luminol and hydrogen peroxide, and the alkaline condition is provided by ammonia
Take 420ml of water, weigh 0.05g of luminol and add it to 420ml of water, it will be found that luminol is difficult to dissolve. 20 ml concentrated ammonia water was mixed with 0.05 g luminol and 420 ml water. It was observed that luminol gradually dissolved in alkaline solution. After the luminol is completely dissolved, 10-20 drops of 30% hydrogen peroxide solution are dropped into it. After mixing, the required solution is obtained, which is recorded as solution a.
Then prepare sodium hypochlorite solution
Measure 20 ml of 10% sodium hypochlorite solution (based on available chlorine content) and 400 ml of water. Mix the two to obtain the required solution, which is recorded as solution B.
PS: the solution can also be obtained by mixing 50 ml 84 disinfectant solution (effective chlorine content is 4%) with 170 ml water.
Mix solution a with solution B
Through these simple steps, the luminol reaction is finished. Desheng biotechnology is a professional manufacturer of vascular additives, in vitro diagnostic reagents, biological buffers, luminescent substrates and enzyme preparations. In terms of chemiluminescence reagents, we have professional R & D and production capacity, and can produce a variety of products. Desheng has been established for many years and has rich production experience. At present, its products are sold to more than 100 countries all over the world with excellent quality and favorable price. Interested in understanding can call consultation, Desheng welcome your call.
