Table 2.

Examples of sample preparation procedures for EBC samples with different final analysis techniques.

Analytical Technique	Sample Preparation	LOD	Ref.
RIA	standard curves obtained using phosphate buffer 0.025 mol/L, pH 7.5, more similar to EBC matrix	10 pg/mL	[91]
	samples stored at −80 °C before analysis	10 pg/mL	[36]
EIA	after sampling no further preparation of the sample is necessary, samples stored at −80 °C before analysis	4–5 g/mL	[25,46,63, 92–95]
	SPE of pooleed sample (35.5 mL), HPLC purification	10 pg/mL	[90]
LC-MS/MS	samples pretreated with 50 μL of immunoaffinity sorbent for 60 min	1 pg/mL	[17]
	after collection sample spiked with 8-isoPGF2α-d4, stored at −80 °C, lyophilization, redissolved in 50 μL of water/methanol (1:1)	8 pg/mL	[85]
	sample spiked with 8-isoPGF2α-d4, pretreated with 50 μL of immunoaffinity sorbent for 60min at 20 °C, centrifuged (3000 rpm for 5 min), immunoaffinity sorbent flushed twice with water, elution with methanol, methanol evaporated, redissolved in 50 μL of mobile phase	1 pg/mL	[14]
LC-MS	immunoaffinity separation	1 pg/mL	[16]