Generic serial and parallel on-line direct-injection using turbulent flow liquid chromatography/tandem mass spectrometry.
The development of turbulent flow chromatography (TFC) has enabled considerable growth in the utility of on-line direct-injection technologies. TFC has now become established in a large number of varied analytical environments, particularly drug discovery/pharmacokinetics, metabolite profiling, combinatorial library purification, pre-clinical and clinical GLP applications. The utility of turbulent flow technology for in-house pre-clinical and clinical quantitative applications has necessitated extensive valve-cleaning procedures, and consequently lengthy cycle-times, to effectively remove the system carry-over. In-house requirements for assay validation require carry-over less than 20% of the lowest level of quantification (LLOQ), corresponding to 0.02% carry-over for a linear calibration range incorporating 3 orders. A generic turbulent flow chromatography protocol has been developed for drug discovery that incorporates polymeric turbulent flow extraction (cyclone) with C18-based reverse-phase chromatography. Further, multiple wash steps are incorporated within the methodology to meet in-house requirements for carry-over. Selection of novel switching-valve materials based on polyarylethyl ketone (PAEK) and Hastelloy/Valcon E autosampler injection hardware has enabled us to significantly impact the cycle-time required to reduce carry-over. Consequently, optimal usage of switching valves has enabled parallel operation for a generic on-line direct-injection methodology to successfully reduce the total cycle-time. Overall reductions from 4 min per sample to 90 s per sample are shown with comparable data quality using a proprietary target molecule from 0.1-100 ng/mL. This paper describes the hardware configuration and methodologies utilized to perform generic serial and parallel on-line direct-injection using a Turboflow HTLC 2300 system.
Lilly Laboratory for Bioanalytical Research, Eli Lilly Canada Inc., 3650 Danforth Avenue, Toronto, M1N 2E8 Canada. Grant_Russell@Lilly.com
Russell P
RP
Grant
Cheryl
C
Cameron
Shelley
S
Mackenzie-McMurter
D002853:Chromatography, Liquid; D007202:Indicators and Reagents; D013058:Mass Spectrometry / Q000295:instrumentation*; D009862:Online Systems; D010316:Particle Size; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results
D007202:Indicators and Reagents