LC-MS/MS assays

The ultra-sensitive ultradian assay measures androgens, corticosteriods and progestogens in human serum and microdialysis samples. This unique method was designed to utilize very low sample volumes to measure time-series steroid profiles in interstitial fluid. 

Sample type and volume: Human serum (50 uL) and interstitial fluid (10 uL)

Analytes measured: Testosterone, Dihydro-testosterone, Cortisol, Cortisone, Aldosterone, 18-hydroxy-Cortisol, DHEAS, 21-deoxycortisol, dexamethasone, Corticosterone, allo-tetrahydrocortisol, 11-deoxycortisol, tetrahydrocortisol, Androstenedione, 17-hydroxy progesterone, Progesterone

Sample processing: Liquid-liquid extraction

LC-MS/MS instrument: Waters Acquity UPLC I-class w/2D technology, Waters Xevo TQ-XS

Read more about the ultradian steroid hormone assay here

This assay quantifies estrogens in human serum samples and can measure estradiol concentrations down to 1.2 pmol/L. 

Sample type and volume: Human serum, 300 uL

Analytes measured: 17β-estradiol, estrone, estriol, ethinylestradiol and estrone sulfate

Sample processing: Protein precipitation, liquid-liquid extraction

LC-MS/MS instrument: Waters Acquity UPLC with 2D technology, Waters Xevo TQ-S

Read more about the estrogens method here 

This method quantifies tamoxifen and 13 metabolites in various human and animal matrixes. The method chromatographically separates clinically relevant isomers of the active tamoxifen metabolites endoxifen and 4-hydroxy-tamoxifen. 

Sample types: Human serum, plasma, bonemarrow plasma, breast milk and tissue. Mouse plasma and tissue. 

Volumes required: 25 mg for tissue and 20 uL for liquid matrixes

Analytes measured: Tamoxifen, ND-tamoxifen, 4OH-tamoxifen (Z, E and Z-4' isomers), 3OH-tamoxifen, endoxifen (Z, E and Z,E-4' isomers), Tamoxifen-N-oxide, NNDD-tamoxifen, Z-α-tamoxifen, cis-β-tamoxifen. 

Sample processing: Protein precipitation (+homogenization for tissue samples)

LC-MS/MS instrument: Waters Acquity UPLC Classic, Waters Xevo TQ-S

The validation of the method in various matrixes have been published separately: 

Tamoxifen in human serum

Tamoxien in bone marrow plasma

Tamoxifen in breast milk

Tamoxifen in human breast tissue

This assay measures the emergency contraception drug Ulipristal Acetate (Ella) and celecoxib, which is a NSAID class painkiller. 

Sample types and volumes: Human and mouse serum, 20 uL

Analytes measured: Ulipristal Acetate (brand name: Ella), Celecoxib (brand name: Celebra)

Sample processing: Protein precipitation

LC-MS/MS instrument: Waters Acquity UPLC Classic, Waters Xevo TQ-S

Publication of the method is in process. Please conctact thomas.helland@uib.no for validation data.