Monday March

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Brenda Tyler
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1 Monday March ASHLEY T WILKS & Billy Boyle Pittcon 2012 Orange County Convention Center Orlando, Fl Developments in Ultra FAIMS Instrumentation for Standalone and Hyphenated Applications

2 Principles in 30 seconds Classical model ν D(h) X = K(E).E(τ) ν D(l) = K(0).E(t) High Field Low Field K(E) / K(0) 1 + α 2 E 2 + α 4 E 4 + α n E 2n Waveform Voltage and Compensation Voltage swept in parallel Separation fundamentally based on the Field Induced Thermal Modulation of ions in the Ion Separator XXX

3 α-model breakdown Model: E C /N = c 3 (E D /N) 3 + c 3 (E D /N) 5 α-model Predicts E C E N at high fields data α-model FAIMS / DMS α-function models DO NOT Fit Very SIMPLE cases (stable monomer product ions) Acetone monomer Butanone monomer DMMP monomer FAIMS / DMS α-function models fit 3

4 Micro-Design / High Voltage & High Frequency separation waveform Ion separator employs multiple serpentine arranged micro-gap spaced electrodes (g = 35µm standard) The length (l) of the filter channel can be varied (300µm standard) Asymmetric Waveform frequency = 27MHz Typical ion residence times of ~30µs Peak operational field is >75kV.cm -1 (~320Td at 1 atmosphere) ±E 4

5 UH-FAIMS Platforms MCD Static Chemical Monitor Electrospray UltraFAIMS-MS LoneStar 5

6 Key Aspect relating Extreme Field operation - Effective Ion Temperature (T eff ) T = Drift gas temperature (K) ζ M K (E/N) = Energy transfer (collisional) efficiency factor = Av. MW of carrier gas = Field specific Ion Mobility (m 2.V.s -1 ) E D /N = Field / number density (V.m 2 ) DMS / FAIMS UH-FAIMS ζ = 0.5 ζ = 0.5 k b = Boltzmann constant (J.K -1 ) 6

7 Features of use of High Field & High Frequency - Ion-neutral collision frequency - 5GHz at 1atm Features Ultra-High Peak Field = much higher peak Effective Ion Temperatures Low field not negligible = much higher average Effective Ion Temperatures High Frequency = fewer ion-neutral collisions in high and low field portion of applied waveform 7

8 Ultra-High Field Operation - Impacts In filter ion transformations/ reactions Desolvation loss of ion-dipole /ioninduced-dipole species M(X n ) +/- M(X n-1 ) +/- + X Adduct dissociation (e.g., ionic H bond cleavage) (M 2 H) + (MH) + + M Fragmentation (covalent site) (ABC) +/- (AB) +/- + C Conformational (geometric), e.g. Barrier to internal rotation Folding (high MW multi-charged molecular ions (peptides, proteins) n+/- n+/- 8

9 Ion dissociation processes ( ) ( ) ~12ns Hot For hypothetical ion dissociation process - ~24ns MA + k M + + A Cool = H -RT E A = Association energy H = enthalpy of Association T eff (E D /N) 2 =.. In filter Dissociation when - 1/ ( ) < ( ) Compensation Field +

10 Ion Transmission; model breakdown Field Dependent Diffusion Losses K 0 = 1.4cm 2.V.s -1 K 0 = 1.8cm 2.V.s -1 K 0 = 2.1cm 2.V.s -1 From Einstein Relationship D II (E D /N) M = Drift gas MW T = Drift gas temp. t res = ion residence time g eff = effective gap size I I (E D /N) f = <F 2 > x F II (molecular ion potential x waveform property) Transmission function - 2 I( ED / N) = exp π. D D. II(Ε /N) 2 XXXXXX res geff t K 0 = 1.4cm 2.V.s -1 K 0 = 1.8cm 2.V.s -1 K 0 = 2.1cm 2.V.s -1 10

11 Ion Kinetics - EXAMPLE; A SIMPLE CASE (Dimer Dissociation) Dimer Monomer + Neutral + Pseudo first order (monomers and neutral can t recombine at low field) - = = [ ] [ ] = [ ] exp / = ln2/ =.. In filter Ion Separator region [ ] [ ] =exp ( ). τ( ) 11

12 Kinetic losses dominate Breakdown Diffusive losses only Real model diffusive & kinetic Dimers - Acetone Butanone DMMP 12

13 Experiment vs. Theory T eff (E D /N) 2 Breakdown 13

14 In filter monomer formation M 2 H + MH + + M Dimer may be predominant at low Field since dimer formation is kinetically / thermodynamically favorable But at higher fields one observes breakdown and dimer re-association cannot occur in the Ion-filter Monomer resurges 14

15 Effective Ion Temperature; a FAIMS vs. UH-FAIMS perspective I A (E C /N) (E D /N) T eff Conversion Monomers Monomers dimers dimers DMS Ultra-FAIMS Normalized Peak Ion Count Linear scanning of E D /N? Yes need data through wide effective ion temperature range (Low & High Field) 15

16 Functional molecules OP1 OP2 OP3 Transmission spectra E C ;E D (Dispersion) spectra c Fragments T eff E D 2 b a Stable ions OP1 OP2 OP3 a Low field principal ions b Low field fragment ions c High field fragment ions Ion Count (pa) 16

17 Negative Ions ClCN B(2-CES): HCN DNT OP1 Transmission spectra 2-6 DNT 2-4 DNT E C ;E D (Dispersion) spectra CN- 2-4 DNT - HF stable ions & fragments K 0 dependent Transmission T eff E D 2 Cl- CN- Smaller molecules K 0 ~ reactant ion GA - Bis(2-CES) - Larger molecules K 0 < reactant ion 2-6 DNT - ClCN B(2CES) OP1 Integrated Ion Count (pa) 17

Mining the E C ;E D Spectrum Large amount of information generated and processed extremely rapidly (second timescales) Gaussian parameters - Peak Width Peak Area Peak Location.

specific Ion behavior Agent level Field specific Ion behavior (e.g. Ion cluster breakdown) Ion (agent) identity Ion current (A.U.) Dispersion Field (Td) 280 210 140 70 0.2 0.

18 Mining the E C ;E D Spectrum Large amount of information generated and processed extremely rapidly (second timescales) Gaussian parameters - Peak Width Peak Area Peak Location.as a function of Dispersion Field Key Information Parameter Peak Width W 1/2 (E D /N) Ion Transmission I A( (E D /N) Peak location E C (E D /N) Information Low field mobility Field specific Ion behavior Agent level Field specific Ion behavior (e.g. Ion cluster breakdown) Ion (agent) identity Ion current (A.U.) Dispersion Field (Td) E c ;E D Spectrum (1) (1) (2) (3) (3) (2) Compensation Field (Td) Fix Field Response Ion Transmission transmission spectrum (3) (2) 1 (1) Integrated ion current (A.U.) 0.1

19 Additional information; Peak width W 1/2 (E D /N) FWHM (W 1/2 ) - / = 4. 2 XXXXXX / At E D /N = 0, D II = D = K(E/N) >> K 0 Dimer breakdown = / 19

20 Ultra-High Fields - Summary Differentiators Enablers Yields Ultra high field operation (> 80kV.cm -1 ), high effective ion temp. Narrow separation electrode gaps (35µm) combined with RF-drivers Data e.g. ion kinetics (fragmentation at high effective ion temp.) Very high frequency separation field (27MHz) pulse time scales on order of ion collision frequency State-of-the-Art high field drivers combined with narrow, precision engineered electrode gaps (35µm) Separation not dependant solely on conventional ion cluster / de-cluster model additional information Very short ion residence time (~30µS) Atmospheric pressure operation Short length (300µm) ion separation channels Ultra high fields & short separation Channels Fast separation E c ;E D scans on few second timescale Extreme Sensitivity - (ppb (v) ) 20

21 Applications Real time gas and vapor detection VOCs, toxic gases / vapors Oil & Gas Food & Beverage Head space sampling Fast response combined with extreme sensitivity Ultra-FAIMS MS LC-UltraFAIMS MS Pharma Proteomics Metabolomics Enhanced selectivity Faster separations (reduced chromatographic time) MS sensitivity enhancement Electrospray UltraFAIMS- MS interface module Electronic drivers 21

22 Food, beverage and Pharma QC direct headspace sampling (complex matrices) Tune system to the separation Sweet Spot 22

23 Direct headspace analysis of Crude Oil 23

24 (LC)-ultraFAIMS-Electrospray-MS e.g. Metabolite separation Ion Intensity LC mass flux LC retention Time Ion Intensity Ion Intensity No FAIMS UltraFAIMS Budesonide assay (without LC) Total ion spectrum MH+ MNa+ Excipient Paroxetine metabolites Compensation Field +/- Comp. Field m/z 24

Acknowledgements Owlstone Team Owlstone Inc 761 Main Avenue Norwalk, CT USA (+ 1) 203 908

25 Acknowledgements Owlstone Team Owlstone Inc 761 Main Avenue Norwalk, CT USA (+ 1) Owlstone Ltd 127 Cambridge Science Park Milton Road Cambridge, UK (+ 44)

Rapid Thermal Modulation Ion Spectrometry (RTMIS) Part 1

Rapid Thermal Modulation Ion Spectrometry (RTMIS) Part 1 Underlying Separation Principles and Model of Operation *Ashley Wilks, Matthew Hart, John Somerville, Andrew Kohel, David Ruiz-Alonso, Paul Boyle,