price of glacial acetic acid_price of glacial acetic acid

Once lysis is complete, the next critical step is the neutralization of the solution. Here, glacial acetic acid comes into play. By adding acetic acid, the pH of the solution is lowered, allowing the renaturation of plasmid DNA while precipitating chromosomal DNA and proteins that had been denatured in the alkaline conditions. The difference in the solubility of plasmid DNA compared to chromosomal DNA and other cellular components is exploited during this step. Plasmid DNA, being smaller and more stable in these conditions, remains in solution while the unwanted components form a precipitate that can be removed by centrifugation.

Occupational exposure to glacial acetic acid, the purest form of acetic acid, can occur through inhalation and skin or eye contact. Acetic acid is corrosive to skin and eyes. The Occupational Safety and Health Administration (OSHA) has set standards for exposure to acetic acid. Acetic acid has an OSHA permissible exposure limit (PEL) of 10 parts per million (ppm) over an 8-hour work shift. Symptoms of exposure to acetic acid vapors at that level can include eye, nose and throat irritation. At 100 ppm, marked lung irritation and possible damage to lungs, eyes and skin might result. Exposure to acetic acid can also cause pharyngeal edema and chronic bronchitis.   In general, exposure to acetic acid in concentrations above those in commercial products and preparations should be avoided, as skin and eye irritation can occur even at relatively highly diluted acid solutions.