Toxicity of the PVP-coated AgNPs to the cervical tissue. a) Normal squamous epithelium and the stroma of ecto-cervical tissues were exposed to Replens gel mixed with 0.15 mg/mL PVP-coated AgNPs for 48 h. Ecto-cervical explants (5 mm) were exposed to either Replens gel alone, which served as a control, or to PVP-coated AgNPs. After 48 h of incubation in a 37°C humidified incubator, the tissues were washed, embedded in paraffin, and stained with hematoxylin and eosin. b) Cervical explants in the upper Transwell chambers were exposed to Replens alone as a control, Raft-medium, or Replens gel containing different concentrations of PVP-coated AgNPs (0.6, 0.3, 0.15, 0.1, 0.05 and 0 mg/mL). After 24 h, the medium containing PVP-coated AgNPs was removed and washed three times with culture media. Cell viability was measured by the CellTiter-Glo® assay. Graphs show values of the means ± standard deviations from three separate experiments. Graphs were created using the SigmaPlot 10.0 software.