Abstract
Purpose: :
To analyze the in vitro cytotoxic effects of Betadine® (Povidone Iodine) on a human conjunctival cell line (IOBA-NHC).
Methods: :
A Normal Human Conjunctival Cell (IOBA-NHC) line was grown in vitro until reaching confluence to allow for sufficient ExtraCellular Matrix (ECM) production, so similar conditions to human conjunctiva could be reached. The day of the experiment, cells-containing wells were washed with 1xDPBS and 1ml of Betadine® was applied at different times and concentrations. After different time applications, wells were washed 3 times with cold 1xDPBS. Cells were trypsinized and viable cells counted by Trypan Blue staining exclusion.
Results: :
Betadine® (Povidone Iodine) usually applied topically before cataract surgery as an antibacterial agent, results toxic to IOBA-NHC cells when applied in vitro at concentrations used during surgery (5%). Gradual 2-fold dilutions decrease the cytotoxic rate, with 6-fold dilution (0.625%) resulting in a survival rate up to 20 times higher with Betadine® acting for 3 minutes (Figure 1). Lower exposure times of IOBA-NHC cells to Betadine® resulted in higher viability gradually increasing with higher Betadine® dilutions (data not shown).
Conclusions: :
Betadine is well known for its bactericidal properties but cytotoxic effects have not yet been evaluated on human conjunctiva. IOBA-NHC cells constitute a good in vitro model for cytotoxic studies of the human conjunctiva. Our results indicate that Betadine® has cytotoxic effects at the usual concentrations used during cataract surgery (5%) and that these effects could also affect the corneal epithelium. The use of lower doses should be considered.
Keywords: ocular irritancy/toxicity testing • conjunctiva • apoptosis/cell death