Trace analysis using ambient ionization on miniature mass spectrometers Zheng Ouyang, R. Graham Cooks, Sandilya Garimella, He Wang and Fatkhulla Tadjimukhamedov Purdue University Miniaturization of Analysis System Sample Collection Lab-Scale 5 lb/2kw Data Interpretation Sample Sample Treatment Sample Treatment Sample Treatment Treatment < 4 kg.2 ft 3 35 W Simple Operation Mini Compact Size Low Cost
Low Temperature Plasma Mini 11 8 lb Discharge Gas <.1 l/min 5kVp-p 2.5 khz <1W AC Paper Spray Discontinuous API D GDEI Pinch Valve RIT EM 5 l/min Diaphragm Desorption Electrospray Ionization Turbo V N2 Discontinuous Atmospheric Pressure Interface (DAPI) GDEI Pinch Valve RIT EM Turbo 5 l/min Diaphragm Scan Function 11 l/s or 5 l/s Pinch Valve Ion Ion Introduction Introduction I II III IV V 1 1 1 1 End Electrode I V +4V V V Multiplier -16V RF - P V AC - P V I. Preionization II.Ionization (ion transfer allowed) 15-3 ms III. Cooling, 25 5 ms IV. Scan, ms V. Postscan Pressure (Torr) (Torr) Pressure +24V Pinch Valve 1 1 2 2 1 1 3 3 1 1 4 4 Analysis Analysis 11 Time Time (s) (s) 22 11 l/s or 5 l/s
Mini with DAPI Analytical performance APCI+ APCI+ Discontinuous API ESI+ ESI+ Discontinuous API GDEI ESI GDEI Pinch Valve Corona Discharge Pinch Valve RIT RIT EM EM 5 l/min Diaphragm Turbo Diaphragm 5 ppb 25 Relative Intensity Intensity (b) 249 125 3 2 15 LOD = 8 ppb 6 1.x1 5 + 8.x1 [M+H] 34 12 5 6.x1 8 5 ppb 5 4.x1 4 5 2.x1 5 11 l/s or 5 l/s Cocaine in Water (by Mini 11) DMMP in Air (by Mini 1) 35 Turbo 5 l/min 11 l/s or 5 l/s 15 2 25 2 25 3 3 35. 1 2 3 4 5 Concentration (ppm) Desorption Electrospray Ionization (DESI) Electrical Potential Solvent (Water) Nebulizing Gas (N2) kv 3-1 L/min Charged solvent spray Samples in Air RDX 5 fmol 5 seconds 223 [RDX + H]+ 74 3 pg 88 12 237 251 CotteCotte-Rodriguez
Low Temperature Plasma (LTP) Probe 1kVpp 2.5 khz < 3 W AC Discharge Gas <.1 l/min 3 C LTQ Da 5pg TNT on Teflon, Discharge Gas: He 3 C Harper, AC, 28 Paper Spray LTQ Data 1 mm 1 mm
Dried Blood Spot Analysis (DBS) for Therapeutic Drug Monitoring (TDM) GLEEVEC (imatinib mesylate) LTQ Data Chemicals analysis on surface Swab surface Sample on filter Paper (with dust and other species) MeOH/Water (1:1) HV Ions Chemicals on a coffee bag 195 [Caffeine+H] + Relative Abundance 15 2
Chemicals analysis on surface Swab surface Sample on filter Paper (with dust and other species) MeOH/Water (1:1) HV Ions 2pg heroin on table surface (~1cm 2 ) 328 37 Relative Abundance 8 6 4 2 211 268 2 24 28 32 36 31 [Heroin+H] + 352 37 Chemicals analysis on surface Swab surface Sample on filter Paper (with dust and other species) MeOH/Water (1:1) HV Ions 8 2pg heroin on hand (~1cm 2 ) [Heroin+H]+ + 37 37 Relative Abundance 6 4 2 211 268 31 328 352 2 25 3 35
HV+ MeOH/Water Ions Relative Abundance 182 64 157 Cocaine on $ 1 Bill 34 34 229 285 34 333 2 3 4 Low Temperature Plasma 5kV p-p 2.5 khz < 1 W AC Discharge Gas <.1 l/min Mini 11 8 lb Paper Spray D Discontinuous API Pinch Valve GDEI RIT EM Desorption Electrospray Ionization 5 l/min Diaphragm Turbo 11 l/s or 5 l/s V N2
LTP-Mini - Melamine in Milk Products Carrier gas c1 c2 c3 c4 5 µg/ml melamine in whole milk, loading volume 3µL (absolute melamine amount of 15ng) Guangming Huang D + Mini 1 Mini 1.5 D 1.6 mm OD Inlet Capillary Swagelok SS Tee Nano ESI DC Compensation Voltage 6.4 mm OD SS tubing Vh Vl Fatkhulla Tadjimukhamedov t Auxiliary Suction,.8 L/min Pinch Valve RIT Electron Multiplier Diaphragm 5 L/s Turbo, 11 L/s
325 nesi D Mini : Cocaine in solutions (5 ppb in acetonitrile or methanol/water, with.1% FA) (a) 34 Acetonitrile/water (b) MeOH/ water 189 191 31 34 375 D off Absolute Intensity (a.u.) 275 11 (c) CV=2.75 V 288 (e) 182 34 CV=2.75 V 34 34 (d) CV= 6. V 34 245 (f) 182 34 CV= 6. V 34 4 D on 175 D on 2 3 2 3 Ion Transfer in Air Carrier gas c1 c2 c3 c4 Mini 1.5 Nano ESI D 1.6 mm OD Inlet Capillary Swagelok SS Tee Pinch Valve RIT DC Compensation Voltage V h 6.4 mm OD SS tubing Auxiliary Suction,.8 L/min Diaphragm Electron Multiplier V l t 5 L/s Turbo, 11 L/s
Flow Dynamics in Ion Transfer Sample PUSH Push and Pull When flow is aligned with the transfer tube axis DESI, EESI, ESI LTP, NanoESI, Sample PULL Tube ID, ¼ Flow Rate: 1.5L/min Tube ID, ¼ Flow Rate: 1.5L/min 4mm ; 3mm 1mm 6mm 95mm Flow Dynamics in Ion Transfer in Real Cases Gas flow not aligned with the transfer tube axis a Sample b c & d b a Air entering 45 o angle with centerline c DESI c d
DESI Sampling Device DESI Inlet Ion Transfer Push mode LTQ Data 5 µg g Cocaine on Glass DESI Sandilya Garimella
Enhancement of S/N Relative Abundance 5 74.17 134. 222.7 34.8 Absolute intensity = 1.E3 1 cm tube DESI ID:.24 5 Absolute intensity = 1.E3 15 cm tube LTQ Data Absolute intensity = 1.E3 5 2 cm tube 2 4 Sandilya Garimella DESI - Mini 1 DESI Mini 1 Pinch Valve GDEI RIT mtorr EM 5 l/min Diaphragm Turbo 11 l/s or 5 l/s 3 ug Cocaine On glass 1 ng Cocaine On glass
LARGE AREA MODIFIED DESI DESI spray LTQ capillary 7/27/29 25 Large Area DESI Sampling LTQ Data DESI 1.5µg Cocaine 1.5µg Ecstasy (MDMA) 194.18 194 4 cm 182.9 34.18 6 Intensity 5 162.91 Cocaine 34.18 Intensity 5 34 Intensity 5 4 3. 2 3 Ecstasy 194.9 245.9 295.91 2 3 2 222.91 261.9 282. 16 18 2 22 24 26 28 3 32 34
Non apprximate Detection 5cm tygon tube, ID ¾ LTP Discharge Gas <.1 l/min 5kV p-p 2.5 khz < 1 W AC 5 ng Cocaine on glass slide Shop vac LTQ Data 33.96 34.29 34 Intensity 5 Intensity 5 182.22 15 2 25 3 35 4 45 5 293.99 35.4 3.2 31.4 36.7 313.6 29 295 3 35 31 315 32 Non apprximate Detection 3 m (1 ft) in stainless steel ¾ diameter conduit 1.7 µg cocaine on glass desorbed 182 5kV p-p 2.5 khz < 1 W AC Discharge Gas <.1 l/min 8 34 Relative Abundance 6 4 119 15 Cocaine MW = 33.35 34 2 15 2 25 3 35 4
Non apprximate Detection 5 meters (16 feet) tygon tube: ID ¾ 1.7 µg Cocaine on glass slide Shop vac suction Discharge Gas <.1 l/min 5kV p-p 2.5 khz < 1 W AC 34 Large Area Mapped with 1.7 µg on glass slide LTP 2 LTP 3 LTP 1 ~ 2 cm
Group Member He Wang Sandilya Garimella Jiangjiang Liu Wei Xu Tsung-Chi Chen Qian Yang Jian Xu Matt A. Kirleis Nick Charipar Jason Harper Prof. R. Graham Cooks