Biocompatibility investigation of different pharmaceutical excipients used in liquid dosage forms.

Aqueous pharmaceutical solutions provide prosperous living conditions for microbiological agents. In order to eliminate these microbes, we use preservatives which can harm human cells as well. Their cytotoxicity is concentration-dependent and the aim of our study was to find how other pharmaceutical excipients modify the cytotoxic attributes of preservatives. We tested the following compounds: methylparaben, benzalkonium chloride, polysorbate 20, Labrasol® and hydroxyethyl cellulose. The MTT tests indicated that surfactants increase the cytotoxicity while polymers may decrease it in some cases.