Fig 1.
Representative IR raw (panel A) and Savitzky-Golay first derivative transformed spectra (panel B) of vaginally inserted swabs, control-dry (rayon swabs), control–water (rayon dipped in water) and control-VSF (rayon dipped in vaginal fluid simulant).
Fig 2.
PCA score plots showing separation of vaginally inserted swabs and various control swab conditions (dry, or treated with water or VFS) using raw spectra (panel A), IR region of 1740–1140 cm-1(panel B), and IR region of 1685–1485 cm-1(panel C).
Table 1.
Summary of classification models developed for identification of vaginal swabs.
Fig 3.
Representative raw infrared spectra (panel A) and Savitzky-Golay first derivative transformed spectra (panel B) of vaginal swabs, vaginal swabs + semen and rayon + semen.
Table 2.
Summary of classification models tested at 5% significance level for identification of vaginal swabs (baseline) from vaginal swabs containing semen and rayon swabs containing semen only.
Table 3.
Summary of classification models developed for identification of vaginal swabs containing HEC placebo gel tested at 5% significance level.
Fig 4.
Raw spectra(4000–650 cm-1) of vaginal swabs (baseline, no placebo insert) and vaginal swabs containing placebo insert.
Table 4.
FTIR predictions summary for placebo insert study (CONRAD D15-134).
Fig 5.
TFV API spectra profile and its corresponding functional peaks in spectra of TFV gel and insert formulations.
Table 5.
Validation of discriminant models developed for identification of vaginal swabs (baseline) and vaginal swabs containing placebo or TFV active inserts.