ethidium bromide
Ethidium bromide (EB) is a highly sensitive fluorescent dye used to observe DNA in agarose and polyacrylamide gels. Ethidium bromide is excited by a standard 302 nm ultraviolet transmission instrument, and emits an orange-red signal. Ethidium bromide contains a tricyclic planar group, which can be embedded between DNA stacking bases. Its binding to DNA has almost no base sequence specificity. In saturated solution with high ionic strength, an ethidium bromide molecule is inserted about every 2.5 bases. When the dye molecule is inserted, its plane group is perpendicular to the helix axis, and it interacts with the upper and lower bases through van der Waals force. The fixed position of the group and its close proximity to the base lead to the fluorescence of the dye bound to DNA. Ethidium bromide has certain toxicity, and skin absorption will cause harm. Irritating to eyes, skin, mucous membrane and upper respiratory tract. It can induce mutation and may lead to cancer. Wear gloves and goggles, protective clothing, and operate carefully in the fume hood.
dimethyl sulfoxide
Dimethyl sulfoxide is a kind of osmotic protective agent, which is widely used. It can reduce the freezing point of cells, reduce the formation of ice crystals, reduce the damage of free radicals to cells, and change the permeability of biofilm to electrolytes, drugs, poisons and metabolites. Studies have shown that DMSO has a serious toxic effect, and it interacts with hydrophobic groups in protein, resulting in protein degeneration, with vascular toxicity and hepatorenal toxicity.
(1) Inhalation: High volatile concentration may cause headache, dizziness and sedation.
(2) Skin: It can burn the skin and make it sting, just like rashes and blisters. If dimethyl sulfoxide comes into contact with water-containing skin, it will produce a thermal reaction.
(3) Absorption: The absorption risk is very low.
Avoid volatilization when using, prepare 1%-5% ammonia water for standby, and rinse skin with plenty of water and dilute ammonia water.
acrylamide
Polyacrylamide is the main component in SDS-PAGE gel. Unpolymerized acrylamide is a potential neurotoxin, which can be absorbed through the skin. The harm of acrylamide mainly causes neurotoxicity and reproductive and developmental toxicity. Neurotoxic effects are manifested in the degeneration of peripheral nerves and brain parts involved in learning, memory and other cognitive functions. The experiment also shows that acrylamide is a possible carcinogen. Epidemiological observation of occupational exposed people shows that long-term low-dose exposure to acrylamide can cause drowsiness, mood and memory changes, hallucinations and tremors, accompanied by glove-like feeling, sweating, muscle weakness and other peripheral neuropathy. It has cumulative toxicity and is not easy to detoxify. Therefore, when weighing acrylamide and methylene bisamide powder, please wear gloves and masks and operate in a chemical fume hood. Polymerized acrylamide is non-toxic, but be careful when using it, because there may be a small amount of unpolymerized acrylamide in it.
dtt
Dithiothreitol (DTT), like mercaptoethanol, is a strong reducing agent, which will give off an unpleasant smell. Can be used as a protective agent for protein to prevent cysteine in protein from being oxidized. It can also be used as an additive in SDS-PAGE electrophoresis to completely break the disulfide bond in protein. Inhalation, swallowing or skin absorption may be harmful to health. When using solid or high concentration storage liquid, wear gloves and goggles and operate in a fume hood.
Benzyl sulfonyl fluoride (PMSF)
Phenylsulfonyl fluoride (PMSF), commonly used in the extraction of protein, is an inhibitor of trypsin and chymotrypsin. It can inhibit serine proteases such as trypsin and chymotrypsin, cysteine protease and acetylcholinesterase, and is a highly toxic cholinesterase inhibitor. It is very destructive to respiratory mucosa, eyes and skin. Inhalation, swallowing or skin absorption can be fatal. Wear suitable gloves and safety glasses and always use them in chemical fume hoods. In case of contact, immediately flush eyes or skin with plenty of water and discard contaminated work clothes.
Diethyl pyrocarbonate DEPC
DEPC (diethyl carbonate) can inactivate many kinds of protein, and it is a strong RNase inhibitor. DEPC is a potential carcinogen, so the operation should be carried out under ventilated conditions as far as possible and avoid contact with skin. DEPC is not toxic, but it is the most toxic by inhalation. Wear a mask when using. If you accidentally get it on your hand, clean it immediately. RNaseAwayTM reagent can replace DEPC, with simple operation, low price and no toxicity. Simply pour RNase on the surface of glassware and plastic ware, and rinse with clear water to remove RNaseAwayTM soaking, so that RNase on the surface of glassware can be quickly removed without residue and interference in subsequent experiments.
ultraviolet ray
Ultraviolet light is a common light source in the laboratory. It can be used for sterilization in aseptic room and for observing DNA in gel. Ultraviolet rays can damage the retina of the eyes. Never use naked eyes and ultraviolet light sources without protective devices. The commonly used ultraviolet light sources in the laboratory are portable ultraviolet lamp and ultraviolet transmission instrument. It can only be observed through filters or safety glass sheets that absorb harmful wavelengths. Ultraviolet rays are also mutagens and carcinogens. In order to minimize exposure, ensure that the ultraviolet light source adopts appropriate protection devices. Wear appropriate protective gloves when operating under ultraviolet light.
methyl alcohol
Methanol is often used to analyze reagents or remove degreasing agents, which is highly toxic and volatile. The toxicity of methanol has the greatest influence on the nervous system and blood system of human body. Intake through digestive tract, respiratory tract or skin will produce toxic reaction, and methanol vapor can damage human respiratory mucosa and vision. Symptoms of acute poisoning include: headache, nausea, stomachache, fatigue, blurred vision and even blindness, and then dyspnea, eventually leading to respiratory center paralysis and death. Chronic toxic reactions are dizziness, lethargy, headache, tinnitus, decreased vision and digestive system disorder. Avoid inhaling its volatile steam mist when using. Wear suitable gloves and safety glasses.