Studies on fluorene stability in different liquid media

When applying chromatography the analyst is faced with problems, among others, caused by changes undergoing in original samples or extract. Storage conditions should ensure their stability. It has been found that degradation processes can not be eliminated entirely, but they can be slowed down considerably. A selection of eight liquid media known as good solvents to store fluorene for a long period of time, have been examined with respect to avoid once of degradation. Fluorene degradation (1 mg l^-1 and 10 mg l^-1) was studied in acetonitrile, methanol, water, dimethyl sulfoxide, hexane, cyclohexane and dichloromethane. The process was monitored for 3 months using HPLC coupled to diode array detection and electrospray MS. The influence of such factors as light, naturally occurring bacterial flora in water samples, and solvent on stability of fluorene was investigated. The results can be helpful in selecting appropriate conditions and allowable time for storing samples extracts for analysis of polycyclic aromatic aromatic hydrocarbons. Therefore, understanding the mechanism responsible for PAHs degradation is required. The fact that salicylic acid and 9-fluorenone are formed during degradation of fluorene indicates that degradation is due to the photochemical and/or microbial processes.