Importance of enantiomeric profiling of chiral drugs in wastewater-based epidemiology and pharmacokinetic relevance

Transcription

1 Importance of enantiomeric profiling of chiral drugs in wastewater-based epidemiology and pharmacokinetic relevance Barbara Kasprzyk-Hordern University of Bath, Department of Chemistry, Faculty of Science, Bath, BA2 7AY, UK

2 Phenomenon of chirality (+)-enantiomer Sedative (-)-enantiomer Teratogen A therapeutic (+)-enantiomer of thalidomide is harmless (has tranquilising properties) but in the human body it undergoes in vivo inter-conversion leading to toxic (-)-enantiomer (teratogenic properties), which leads to malformations of embryos if administered to pregnant woman

3 Phenomenon of chirality More than half of the drugs currently in use are chiral compounds and many of these are marketed as racemates Worldwide sales of chiral drugs in single-enantiomer form continuously increase There is at the present a tendency in the pharmaceutical industry to switch from racemates to single enantiomers

4 NSAIDs, analgesics and anaesthetics CNS drugs: antipsychotic drugs, antidepressants, sedative/hypnotics, CNS stimulants and drugs used for ADHD, drugs used in neurological disorders Cardiovascular drugs: lipid regulating drugs, betaadrenoceptor blocking drugs, antihypertensives, anticoagulants, calcium channel blockers, anti-arrhythmic drugs Respiratory drugs: bronchodilators, antihistamines, decongestants Gastro-intestinal drugs: proton pump inhibitors, H2- receptor antagonists Antimicrobials Antineoplastics Illicit drugs Phenomenon of chirality

5 Global market racemic switches Chiral drug Marketed as Prescription in England [kg year -1 ]* Ibuprofen Dexibuprofen Racemate S(+)-enantiomer Ketoprofen Dexketoprofen Racemate S(+)-enantiomer Citalopram Escitalopram Racemate S(+)-enantiomer meprazole Esomeprazole Racemate S(-)-enantiomer Cetrizine Levocetrizine Racemate R(-)-enantiomer * - data obtained from National Heath Service

6 Phenomenon of chirality Chiral drugs produced in their racemic form can be divided into two groups: drugs with only one major bioactive enantiomer (e.g. propranolol, salbutamol, verapamil, warfarin) drugs with two bioactive enantiomers: - equipotent (e.g. flecainide, mexiletine) - with qualitatively different action (e.g. labetalol, ketamine)

7 Enantiomers of chiral drugs can be metabolised: at different rates (quantitative differences) by different routes (qualitative differences) with retaining the same chiral centre with an introduction of another chiral centre Phenomenon of chirality H H * S/R-warfarin H 6-hydroxywarfarin (metabolism pathway for both (S)- and (R)-warfarin) * H H H * * H * Warfarin alcohol (major metabolism pathway for (R)-warfarin) 7-hydroxywarfarin (major metabolism pathway for (S)-warfarin)

8 Phenomenon of chirality Metabolism can also lead to: the removal of chiral centre (e.g. omeprazole) H 3 C meprazole (chiral) H 3 C N * S N N H N S N N H Sulfone (achiral) enzymatic chiral inversion (e.g. NSAIDs) Interspecies differences in the stereoselectivity of metabolism and elimination are very common: Clearance of propranolol Clearance of warfarin S>R in dog S<R in human S>R in human S<R in rat

9 PRINCIPLES F CHIRALITY Enantiomers of the same chiral molecule have similar physicochemical properties but may differ in their biological properties Enantiomers of chiral drugs reveal different potency: S(+)-enantiomers of AMPH-derived drugs have much higher stimulant activity than R(-)-enantiomers S(+)-MDMA is more amphetamine-like stimulant and R( )-MDMA is more hallucinogenic S-ibuprofen is 100x more potent than R-ibuprofen S(-)-enantiomers of beta-blockers reveal much higher potency in humans Cardiovascular effects of verapamil are mediated by S(-)-enantiomer Chiral drugs have stereoselective disposition in the body: S(+)-enantiomers of amphetamine-derived drugs metabolise faster in human than R(-)-enantiomers

10 Analysis of chiral biomarkers Department of Chemistry R ( - ) - AMPH S (+) - AMPH R ( - ) - MDMA S (+) - MDMA S (+) - MDA R ( - ) - MDA RP (C18)-UPLC-QqQ RP-chiral (CBH) LC-QqQ B. Kasprzyk-Hordern, D. Baker, STTEN, 423 (2012) 142

11 ANALYSIS F CHIRAL DRUGS IN LIQUID MATRICES SPE (HLB, 60mg) Condition: 4mL MeH, 4mL H 2 ; Sample load: 100mL wastewater; 500mL river water; Elution: 4mL MeH; Evaporation and reconstitution to 0.5mL with mobile phase Column 1: CBH UPLC Column 2: Chirobiotic V (100x2.1mm; 5um); 90% H 2, 10% IPA, 1mM NH4Ac; 25 o C, ml/min; isocratic (250x2.1mm; 5um); 100% MeH, 4mM NH4Ac, 0.005% HCH; 25 o C, 0.1 ml/min; isocratic Mass Spectrometry MS1: (ESI+) QqQ (Waters TQD) MS2: (ESI+) QTF (micrtfq, Bruker)

12 1R,2S(-)-Ephedrine 1S,2S(+)-Pseudoephedrine R 1R,2S(-)-Ephedrine 1S,2S(+)-Pseudoephedrine E1-Venlafaxine E2-Venlafaxine R(-)-AMPH S(+)-AMPH R(-)-MDMA S(+)-MDMA LC-MS/MS E1-Venlafaxine chromatograms of chiral E2-Venlafaxine drugs in wastewater influent Column: CBH (100x2.1mm; 5um); 90% H 2, S(+)-METH 10% IPA, 1mM NH4Ac; 25 o C, ml/min; isocratic R(-)-METH MS: TQD S(+)-METH S(+)-MDA R(-)-Atenolol S(+)-Atenolol R(-)-METH R(-)-MDA R(-)-Atenolol S(+)-Atenolol B.Kasprzyk-Hordern, V.V.R. Kondakal, D.R. Baker, J. Chromatogr 1217 (2010) 4575

13 LC-MS/MS chromatograms of chiral drugs in river water spiked with chiral drugs and extracted by SPE (concentration, 100 ng/l) Column: Chirobiotic V (100 x 2.1mm; 5um); 100% MeH, 4mM NH4Ac; 0.005%FA 25 o C, 0.1 ml/min; isocratic MS: QTF J. Bagnall, S.E. Evans, M.T. Wort, A.T. Lubben, B. Kasprzyk- Hordern, J. Chromatogr 1249(2012)115

14 Importance of chirality Wastewater-based epidemiology Distinction between consumption and direct disposal Identification of whether drug residue results from consumption of illicit drug or metabolism of other (illicit) drug Distinction between legal and illicit use of drugs Verification of the method of synthesis of illicit drugs Verification of potency of abused drugs

15 mirror image Department of Chemistry Importance: Potency and metabolism Synthesis: Non-stereoselective method S(+)-MDMA More AMPH-like stimulant Metabolises faster in humans HN H H NH R(-)-MDMA More hallucinogenic Dominant in urine Enantiomers of MDMA

16 * * HN NH 2 MDMA No medical use Produced as racemate Metabolism favours S(+)-enantiomer Preferential metabolism of S(+)- MDMA leads to enrichment of MDMA with R(-)-enantiomer and formation of S(+)-MDA (twice as much S(+)-MDA is excreted in urine as compared to R(-)-MDA) MDA No medical use Produced as racemate Metabolism favours S(+)-enantiomer Preferential metabolism of S(+)-MDA leads to enrichment of MDA with R(-)- enantiomer

17 WWTP1 WWTP2 WWTP3 WWTP4 WWTP5 WWTP6 WWTP7 WWTP1 WWTP2 WWTP3 WWTP4 WWTP5 WWTP6 WWTP7 Load [g/day] WWTP1 WWTP2 WWTP3 WWTP4 WWTP5 WWTP6 WWTP7 Enantiomeric fraction Concentration [ng/l] Department of Chemistry MDMA IN 7 WWTPs IN ENGLAND JAN FEB MAR APR AUG JAN FEB MAR APR AUG EF = Excess of R(-)-MDMA R MDMA R MDMA + S + MDMA JAN MAR HN MDMA * FEB APR B. Kasprzyk-Hordern, D. Baker, STTEN, 423 (2012) 142

18 WWTP1 WWTP2 WWTP3 WWTP4 WWTP5 WWTP6 WWTP7 WWTP1 WWTP2 WWTP3 WWTP4 WWTP5 WWTP6 WWTP7 Load [g/day] WWTP1 WWTP2 WWTP3 WWTP4 WWTP5 WWTP6 WWTP7 Enantiomeric fraction Concentration [ng/l] Department of Chemistry MDA in 7 WWTPs in England JAN FEB MAR APR AUG JAN FEB MAR APR AUG EF = Excess of S(+)-MDA MDA NH 2 R MDA R MDA + S + MDA * JAN FEB MAR APR AUG B. Kasprzyk-Hordern, D. Baker, STTEN, 423 (2012) 142

19 mg/day/1000 inh. Load [g/day] Department of Chemistry MDMA Utrecht averaged weekly loads in mg/d/1000 i.e. MDMA Thu Fri Sat Sun Mon Tue Wed Fri STP Utrecht Days Belgium, Antwerp Belgium, Brussels Croatia, Zagreb Czech Rep., Budweis Emke et al., STTEN 487 (2014) Finland, Helsinki Finland, Turku France, Paris Italy, Milan NL, Amsterdam NL, Eindhoven NL, Utrecht Norway, slo Spain, Barcelona Spain, Castellon Spain, Santiago Spain, Valencia Sweden, Stockholm < < < Sweden, Umea UK, London SAMPLING: 10/03/ /03/ /02/ /02/2010

20 MDMA Utrecht March 2011 two people were arrested for having a facility to manufacture XTC pills -Typical flow 1m/s -1.8 km distance -Travel time 30 min Emke et al., STTEN 487 (2014)

21 Load [g/day] Department of Chemistry MDMA Utrecht excess of R(-)-MDMA CNSUMPTIN Thu Fri Sat Sun Mon Tue Wed Fri Days Excess of R(-)-MDMA STP Utrecht racemate DIRECT DISPSAL Emke et al., STTEN 487 (2014)

22 Conclusions Enantiomeric profiling of chiral drugs in environmental matrices provides yet another dimension to wastewater-based epidemiology as it helps with: Distinction between legal and illicit use of drugs Verification of the method of synthesis of illicit drugs Identification of whether drug residue results from consumption of illicit drug or metabolism of other (illicit) drug Verification of potency of abused drugs