LC-MS/MS methods for the quantification of sulfasalazine and sulfapyridine in various matrices: application to a pharmacokinetic study

Date
2022-11
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Introduction: An early phase clinical trial which took place at The Mercy Hospital for Women in Australia assessed the use of sulfasalazine as a treatment for preterm pre-eclampsia. This project consisted of the development and validation of a Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) method according to the Food and Drug Administration (FDA) and European Medicines Agency (EMA) guidelines to simultaneously quantitate sulfasalazine and its metabolite, sulfapyridine, in placenta for pharmacokinetic analysis. Methods: A Shimadzu 8040 mass spectrometer was operated in multiple reaction monitoring (MRM) mode to monitor the mass-to-charge (m/z) transition of the protonated precursor ions m/z 398.90 and m/z 250.07 to the product ions m/z 381.05 and m/z 156.00 for sulfasalazine and sulfapyridine, respectively. Sulfasalazine-d4 and sulfapyridine-d4 were used as internal standards. 100 μL of placental tissue homogenate was extracted using acetonitrile:methanol (90:10, v/v) and the supernatant was eluted through hydrophilic-lipophilic balanced cartridges. The extraction procedure was followed by liquid chromatographic separation using a Poroshell C18 column. Gradient elution using a mobile phase combination of water + 0.1% formic acid (A) and acetonitrile:methanol (90:10, v/v) + 0.1% formic acid (B) was used. Accuracy and precision were assessed over three consecutive, independent runs. The ratios of analyte peak area to internal standard peak area were plotted against the nominal concentrations to generate a calibration curve which fits a quadratic regression (weighted by 1/x, x= concentration) over the range 30-30 000 ng/mL for both sulfasalazine and sulfapyridine. Results and Discussion: The average accuracy of calibration standards during inter-day validations ranged from 94.2-103.2% (%CV= 1.4-10.8) for sulfasalazine and 96.6-103.4% (%CV= 1.4-8.3) for sulfapyridine. The accuracy of quality controls ranged from 101.6-112.7% (%CV= 4.4-6.7) and 97.4-108.4% (%CV= 3.7-10.0) for sulfasalazine and sulfapyridine, respectively. Endogenous matrix components were shown to have no impact on the reproducibility of the method when placental tissue from six different sources were analysed. The average recovery of sulfasalazine and sulfapyridine from placental tissue homogenate was 121.5% and 119.6%, respectively. Autosampler stability experiments indicated that placental tissue homogenate extracts were stable on instrument for up to 48-hours at the method-defined temperature. Re-injection reproducibility experiments illustrated that the method remained accurate and precise for analysis of both analytes following a re-injection of a batch for up to 48 hours after the initial injection. Furthermore, sulfasalazine and sulfapyridine were found to be stable in placental tissue homogenate for 10 days when stored at -80 °C, for six hours when left on bench at room temperature, and when subjected to three-freeze thaw cycles. Upon analysis of patient samples (n= 9), the concentrations ranged from 491-4201 ng/g tissue for sulfasalazine and 637-26756 ng/g tissue for sulfapyridine, with two patient samples below the limit of quantitation (BLQ) of the assay for both analytes. Conclusion: An LC-MS/MS method for the quantification of sulfasalazine and sulfapyridine in human placenta was successfully validated and applied to a clinical study to evaluate the efficacy of sulfasalazine as an intervention for pre-eclampsia.
AFRIKAANS OPSOMMING: Inleiding: ʼn Vroeë-fase kliniese proef wat by The Mercy Hospital for Women in Australië gedoen is, het die gebruik van sulfasalasien as behandeling vir premature pre-eklampsie geassesseer. Hierdie projek het die ontwikkeling en bevestiging behels van ʼn vloeistofchromatografie-tandemmassaspektrometrie-metode (LC-MS/MS-) ingevolge die riglyne van die Food and Drug Administration (FDA) en die European Medicines Agency (EMA) om terselfdertyd sulfasalasien en die metaboliet daarvan, sulfapiridien, vir farmakokinetiese ontleding in die plasenta te kwantifiseer. Metodes: ʼn Shimadzu 8040-massaspektrometer is in meervoudige reaksiemoniteringsmodus (MRM-) gebruik om die massa-tot-lading-oorgang (m/z-) van die geprotoneerde voorloper-ione m/z 398.90 en m/z 250.07 na die produk-ione m/z 381.05 en m/z 156.00 vir sulfasalasien en sulfapiridien, onderskeidelik, te moniteer. Sulfasalasien-d4 en sulfapiridien-d4 is as interne standaarde gebruik. 100 μL plasenta-weefselhomogenaat is met asetonitriel:metanol (90:10, v/v) onttrek en die bodrywende stof is met hidrofilies-lipofilies-gebalanseerde patrone geëlueer. Die ekstraksieprosedure is gevolg deur vloeistofchromatografiese skeiding met ʼn Poroshell C18-kolom. Gradiënt-eluëring is gedoen met behulp van ʼn mobiele fasekombinasie van water + 0.1% metanoësuur (A) en asetonitriel:metanol (90:10, v/v) + 0.1% metanoësuur (B). Akkuraatheid en presisie is oor drie opeenvolgende, onafhanklike lopies geassesseer. Die verhoudings van die analiet-piekoppervlakte tot die standaard piekoppervlakte is aangestip teen die nominale konsentrasies om ʼn kalibreringskromme te lewer wat pas by ʼn kwadratiese regressie (beswaar met 1/x, x= konsentrasie) bó die reeks 30-30 000 ng/mL vir sulfasalasien en sulfapiridien. Resultate en Bespreking: Die gemiddelde akkuraatheid van kalibreringstandaarde tydens interdaaglikse bevestigings het gewissel van 94.2 tot 103.2% (%CV= 1.4-10.8) vir sulfasalasien en van 96.6 tot 103.4% (%CV= 1.4-8.3) vir sulfapiridien. Die akkuraatheid van gehaltebeheermaatreëls het gewissel van 101.6 tot 112.7% (%CV= 4.4-6.7) en van 97.4 tot 108.4% (%CV= 3.7-10.0) vir sulfasalasien en sulfapiridien, onderskeidelik. Daar is getoon dat endogene matrikskomponente geen impak op die herhaalbaarheid van die metode het nie, deur plasentaweefsel uit ses verskillende bronne te ontleed. Die gemiddelde onttrekking van sulfasalasien en sulfapiridien uit die plasentaweefselhomogenaat was 121.5% en 119.6%, onderskeidelik. Stabiliteitsproewe met ʼn outomatiese monsternemer het aangedui dat uittreksels uit die plasentaweefselhomogenaat instrumentstabiel was vir tot en met 48 uur teen die temperatuur wat vir die metode omskryf is. Herinspuitingsherhaalbaarheidsproewe het getoon dat die metode akkuraat en presies vir ontleding van albei analiete bly, ná die herinspuiting van ʼn bondel tot en met 48 uur ná die aanvanklike inspuiting. Voorts is bevind dat sulfasalasien en sulfapiridien vir 10 dae lank stabiel in plasentaweefselhomogenaat bly as dit teen -80 °C geberg word, vir ses ure as dit teen kamertemperatuur op die werksbank gelaat word en ook as dit aan drie vries-ontdooi-siklusse onderwerp word. Met ontleding van die pasiëntmonsters (n= 9) het die konsentrasies gewissel van 491 tot 4201 ng/g weefsel vir sulfasalasien en 637 tot 26756 ng/g weefsel vir sulfapiridien, met twee pasiëntmonsters wat onder die kwantifiseringsperk (BLQ) van die toets vir albei analiete is.
Description
Thesis (MSc) -- Stellenbosch University, 2022.
Keywords
Tandem mass spectrometry, Preeclampsia -- Treatment, Placental extracts, UCTD
Citation