TLC analysis.

<p>Results for a levonorgestrel standard, sample 1 (positive control), and sample 2a observed under 254 nm light.</p

HPLC-DAD analysis.

<p>HPLC chromatograms from assay / content uniformity analysis for a levonorgestrel standard, sample 1 (positive control), and sample 2a.</p

2D DOSY ¹H NMR analysis.

<p>Spectra (log D vs. chemical shift) for levonorgestrel-containing (A) and sample 2a (B) contraceptive tablets dissolved in CD₄O:D₂O (80∶20 v/v). Signals observed at 3.3 ppm and in the range 4.6–5 ppm are due to the deuterated solvent mixture.</p

UHPLC-IMS-TOF-MS analysis.

<p>Extracted ion chromatogram (A) and extracted ion mobility chronogram (B) for a levonorgestrel standard with <i>m/z</i> 313.2168±0.005. Extracted ion chromatogram (C) and extracted ion mobility chronogram (D) for sulfamethoxazole standard with <i>m/z</i> 254.0599±0.005. Extracted ion chromatogram (E) and extracted ion mobility chronogram (F) for sulfamethoxazole in the poor quality contraceptive tablet with <i>m/z</i> 254.0599±0.005. Mass spectra for the target compounds are displayed as insets.</p

Precursor ion, fragmentor voltage, collision cell voltage, and product ions for sulfamethoxazole MRM analysis.

Q<p>Quantifying ion; ^C Confirming ion.</p

Summary of results for the ECP quality survey^a.

a<p>Product Labels – number indicates a different brand, where a subsequent letter indicates a different batch. Bold text indicates non-compliance. With the exception of 2a, all samples yielded compliant results for identification (TLC and confirmation of levonorgestrel through the HPLC evaluation for dextronorgestrel). No sample showed evidence of dextronorgestrel.</p>b<p>Dissolution presented with the stage required and average result.</p>c<p>Related Substances – the level of any single related substance (S) should be less than 1.0% and the total amount of related substances (T) should be less than 2.0%.</p>d<p>Assay and Content Uniformity results presented as the average results and the minimum / maximum result found.</p>e<p>Only Stage 1 was conducted because 3 tablets were found to be below 60%.</p>f<p>No active release was observed on the 6 tablets tested. Additional tablets were tested for longer periods of release (1 hour) and observed ∼2–5% release of active.</p>g<p>A single peak was observed in the chromatogram (other than for levonorgestrel) which made a large contribution to the level of observed impurities.</p>h<p>30 tablets tested.</p