A Multi-Class Method for the Determination of Antibiotics and Growth Promoters in Aquaculture Products by LC-MS Ryan Gibbs, CFIA Dartmouth Lab 2017 North American Chemical Residue Workshop July 26, 2017 (Canadian Food Inspection Agency), all rights reserved. Use without permission is prohibited.
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 2
Outline 1. Overview CFIA Food Safety Laboratory Network Dartmouth Lab 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 3
CFIA Food Safety Labs CFIA created in 1997 Mission Statement: Dedicated to safeguarding food, animals and plants, which enhances the health and well-being of Canada's people, environment and economy 9 food safety laboratories across Canada Other laboratories for plant and animal health 7 Chemistry laboratories specialized to deliver specific testing programs 4
CFIA Food Safety Labs Longueuil, QC & St-Hyacinthe, QC Burnaby, BC Calgary, AB Saskatoon, SK Toronto, ON Ottawa, ON (2 Labs) Dartmouth, NS 5
Dartmouth Laboratory is the national center of expertise for: Therapeutants in fish Toxic elements in food Marine shellfish biotoxins Dartmouth Lab Accredited by Standards Council of Canada CAN-P-4E (ISO 17025) ISO 1595 6
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 7
Current Testing Therapeutants in Fish Constantly expanding scope of analysis Antibiotics, pesticides and growth promoters Currently 14 single class methods 4 Tetracyclines (TC) 20 Sulfonamides (SULF) 11 Quinolones (FQL) 5 Triphenylmethane Dyes (DYES) 4 Amphenicols (FEN) 1 Macrolide (ERY) 7 Nitroimidazoles (NI) 3 Stilbenes (SB) 5 Steroids (STR) 4 Nitrofurans (NF) 2 Avermectins (IVR/EMA) 1 Benzoylureas (TEF) 2 Pyrethroids (CYP) 4 Carbapenems (CARB) Starting Fall 2017 8
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method Extraction Chromatography 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 9
New Multi-Class Method Simple acidic organic extraction Remove some organic phase with N 2 Spin to remove particulate Analysis by LC-MS Matrix matched calibration standards Weigh sample (2g) Add acidic MeCN (80% + 0.1% FA) Homogenize, sonicate, centrifuge (5,250 g s) Transfer supernatent and make to 20 ml Evaporate 5 ml portion to 3 ml Reconstitute to 5 ml w/ H 2 O Centrifuge 1 ml portion (16k g s) Analyze (LC-MS) 10
New Multi-Class Method 2 injections per sample to optimize peak shape and sensitivity Mobile Phase A UHPLC Conditions 5 mm NH 4 HCO 2 + 0.1% Formic Acid 0.1% AcOH Mobile Phase B MeCN 0.1% AcOH in MeCN Column 50 x 2.1 mm, 1.8 µm Waters HSST3 (w/ guard) Flow (ml/min) 0.5 Gradient Conditions Time (min) %B Initial 0 0.5 0 Column Temperature ( C) Injection Volume (µl) 30 C 3 3.5 95 4.5 95 11
New Multi-Class Method Instrumentation Waters I-Class UPLC coupled to a TQ-S Micro 12
New Multi-Class Method Instrumentation Agilent 1290 UHPLC coupled to a Sciex 5500 QTRAP 13
New Multi-Class Method Instrumentation Waters 1 st Gen UPLC coupled to a Thermo Q-Exactive for HRAM work 14
New Multi-Class Method Ammonium Formate Erythromycin Steroids Quinolones TPMDs Sulfonamides Time (Min) 15
New Multi-Class Method Acetic Acid Amphenicols Stilbenes Nitromidazoles Tetracyclines Time (Min) 16
New Multi-Class Method Workflow Single transition monitored initially (screen) Re-inject/Re-extract suspected positives (confirm/quantify) QqQ System with 2 or 3 transitions monitored HRAM system with SIM targeted MS/MS 70k resolution 17
New Multi-Class Method 0.3 ng/g CAP In Shrimp 18
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 19
Method Validation Overview 1. Multiple goals of this method validation: Ensure method is fit for purpose WRT LOQs, accuracy, precision, uncertainty, analyst/instrument bias, etc. Prove QqQ confirmatory capability Evaluate accurate mass confirmation criteria 2. Method to be used in a Food Safety Survey in September 2017 20
Class Method Validation Detection Limits LOD Range (ng/g) LOQ Range (ng/g) Comments Sulfonamides 0.2 1 0.3 3 SNL/SGD LOD @ 17/30 Quinolones 0.2 0.7 0.3 2 Amphenicols 0.1 0.7 0.3 2 FLRA LOD @ 30 Nitromidazoles 0.7 2 2 5 Erythromycin 2 5 Tetracyclines 4 7 10 20 TPMDs 0.1 0.3 0.3 1 Steroids 0.2 0.4 0.5 1 Stilbenes 0.5 1 2 3 Used USEPA 40 CFR, Part 136, Appendix B procedure for LODs 21
Method Validation Plan Salmon, Shrimp & Tilapia used as representative matrices For each matrix, mixed standard was spiked on tissue 3 x levels (LOQ, 3LOQ, 25LOQ) 5 x replicates/day 3 days Repeated by second analyst on another instrument with independently prepared solutions 22
20% 10% Method Validation Accuracy Deviation from 100% Recovery 0% -10% -20% -30% -40% 56 of 60 compounds between 80-110% Outliers Erythromycin (~65%) Formic acid in extraction TC & CTC (~75%) Epimerization Sulfamoxole (~115%) LOQ level = 144% 3LOQ and 25 LOQ are fine ERY TC CTC CV SQX SNL SCP SMR SGD SMM SDM SPY SMZ SDZ SAA SDX STZ SMP TAP OMP SMX CAP CIPRO FLMQ SMZL HEX abold NAN NLDX TMP MARBO DIEN BG MT RNZ DES bbold MNZ NOR LCV DANO DIFLOX MNZ-OH LMG EPINAN SARA FLR OXO ORBI MG ENRO DOX FLRA HMMNI DMZ IPZ-OH SIX IPZ OTC SXL 23
50% Method Validation Precision @ LOQ Repeatability Intermediate Precision 40% Single Analyst Repeatability 57 of 60 compounds 22% Multi-Analyst Precision 56 of 60 compounds 22% 30% 20% 10% 0% SDM OMP OTC MNZ-OH DMZ MNZ FLMQ DOX MT SDX SQX TMP FLRA MARBO RNZ DIFLOX SAA SMX SCP SMP STZ SDZ HMMNI SNL IPZ SPY SMM SMZ TC NOR bbold IPZ-OH NAN SMR BG SARA SMZL ENRO SIX OXO CTC SXL NLDX EPINAN SGD CIPRO DIEN ORBI DANO FLR TAP abold MG CV CAP DES HEX LMG LCV ERY 24
50% Method Validation Precision @ 3 x LOQ Repeatability Intermediate Precision 40% 30% Single Analyst Repeatability 57 of 60 compounds 15% Multi-Analyst Precision 53 of 60 compounds 15% 20% 10% 0% MNZ-OH MT SDX MNZ OMP MG SMZ SDZ bbold SPY OTC SDM RNZ SMX SMR TMP MARBO STZ CIPRO NAN CV DMZ SAA SCP TAP abold BG DOX DIFLOX FLRA NOR SIX FLMQ SNL SXL SMP DANO SQX TC EPINAN OXO SMM IPZ SARA NLDX ENRO DES DIEN ORBI FLR IPZ-OH CTC SMZL HEX HMMNI SGD CAP LMG LCV ERY 25
50% Method Validation Precision @ 25 x LOQ 40% Single Analyst Repeatability 58 of 60 compounds 15% Outliers ERY Acid Stability Repeatability Intermediate Precision 30% 20% Multi-Analyst Precision 57 of 60 compounds 15% Leuco Forms of TPMDs Conversion? 10% 0% bbold STZ MT abold MNZ-OH MG MNZ SMX OMP TMP NAN RNZ SPY SDX TAP FLMQ HMMNI OTC SDZ MARBO BG DES SAA SMZ SIX SXL NLDX SMR HEX OXO CIPRO DIFLOX DANO CAP FLRA TC ENRO DMZ SCP NOR CV SMZL DIEN DOX SDM SARA FLR EPINAN SMM SNL IPZ SGD SQX ORBI IPZ-OH CTC SMP LMG LCV ERY 26
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches Unit Resolution QqQ HRAM 6. Handling Difficult Compounds 7. Conclusion 27
Confirmation Approaches QqQ Same chromatographic method Monitor 2 or 3 structurally significant fragments Maximize dwell time 0.3 ng/g CAP spiked in Shrimp 321 > 152 321 > 257 Criteria Retention time ± 2.5% Peak-to-Peak S/N of 3x for at least 2 transitions 2.05 2.10 2.15 2.20 2.25 2.30 Time (min) 1.0 ng/g ENRO spiked in Shrimp 360 > 316 360 > 245 Ion ratios within 2002/657/EC limits (Typically ±20%) 1.75 1.80 1.85 1.90 Time (min) 28
Confirmation Approaches HRAM Same Chromatographic Method Alternating SIM / Targeted MS/MS scans 70k SIM resolution, 35k MS/MS resolution Criteria Retention time ± 2.5% ±5 ppm mass accuracy on SIM precursor and at least 2 fragments 29
Confirmation Approaches HRAM 1.0 ng/g ENRO spiked in Salmon 30
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 31
Handling Difficult Compounds Method is fit for purpose for the majority of compounds A few problematic compounds exist Tetracyclines (epimerization) Erythromycin (Accuracy & Precision) TPMDs (Precision) Poor chromatography for some of the polar early eluting compounds 32
Handling Difficult Compounds Tetracyclines: Recovery for TC and CTC is low due to conversion CTC: 3LOQ Spike ~95% recovery for total tetracycline CTC: 3LOQ MM Standard 33
Handling Difficult Compounds Erythromycin recovery and precision poor Acid in extraction solution causes breakdown Even with low recovery, method is fit for purpose to screen for ERY Targeted single class method for follow up quantitation Evaluating ERY in ongoing carbapenem method validation 34
Handling Difficult Compounds Poor TPMD precision Potentially caused by conversion between chromic and leuco forms Radiolabelled internal standards available Consider IS for future quantitative work 35
Handling Difficult Compounds Early Eluters Small polar molecules partially unretained when injected in ~40% MeCN SNL, SGD, FLRA, MNZ-OH SNL SGD Compromise on injection volume Peak gives acceptable results Fit for screening purposes Confirm with single class method FLRA MNZ-OH 36
Outline 1. Overview 2. Current Testing 3. New Multi-Class Method 4. Method Validation 5. Confirmation Approaches 6. Handling Difficult Compounds 7. Conclusion 37
Conclusion Multi-Class method in aquaculture products validated for 60 compounds Fully quantitative/confirmatory method for 52 compounds Acceptable screening method for FLRA, SNL, SGD, LMG, LCV and ERY Summed peaks are acceptable for total tetracyclines QqQ and HRAM confirmatory options 38
Conclusion Replacing multiple single class methods with a multiclass method provides significant efficiency gains Analyst time Consumable costs Instrument Capacity/Maintenance Quality system maintenance requirements Increased laboratory testing capacity 39
Photo Credit: Dr. M. Quilliam, National Research Council, Halifax, NS 40