Molecular depth profiling of multilayer organic films is now an established protocol for cluster secondary ion mass spectrometry (SIMS). The results show successful depth profiles when taken at 90K. Mixing is observed at the interfaces of the films due to primary ion bombardment but this mixing does not recreate the conditions necessary for ionization enhancement. SIMS. The second purpose is to cause Kobe0065 mixing of the matrix layers with the subsequent organic layers underneath. The intentional primary ion bombardment induced mixing of unique layers in depth profiling has been exploited previously. It is known that this matrix/analyte ratio is crucial to the ionization behavior in MeSIMS experiments and utilizing primary-ion induced mixing of the matrix/analyte system may produce ideal stoichiometric conditions for ionization enhancement in the depth profile analysis. Should the ideal conditions be met an increase in ion signal from the organic molecule may be observable in the plotted depth profile. Kobe0065 Materials and methods Thin film preparation DPPC was obtained from Avanti Polar Lipids (Alabaster AL) PHE from Sigma Aldrich (St. Louis MO) and D2O from Acros Organics (Geer Belgium). DPPC films were prepared by spin-coating a 5 μL aliquot of 20 mg/mL DPPC in chloroform onto a 5×5 mm2 Si wafer (Ted Pella Redding CA) at 3500 rpm for 30s yielding 100nm thick films. PHE samples were created by physical vapor desorption (PVD) onto a Si wafer. The PVD chamber continues to be useful for PHE thin-film preparation previously.Samples were stored in a dessicator until make use of. After the preliminary Kobe0065 test planning the wafers had been installed onto a Cu test holder and put in to the mass spectrometer Kobe0065 which provides the PVD chamber. The test stop/wafer was cooled within the test stage to 90K after that put into PVD chamber where warmed DHB had been subliming. Following a full minute of deposition a 200nm film of DHB was deposited onto the wafer/organic film. Rigtht after deposition the examples had been inserted in to the cooled stage within the evaluation chamber and examined. Me-SIMS Assessment Spectra An evaluation of DPPC with and without DHB matrix are likened for baseline measurements. The analytes had been dissolved in solutions of just one 1:1 acetonitrile:drinking water (ACN:H2O) where either clear water or drinking water containing triflrouoracetic acidity (TFA) was utilized. 0.5M DHB and 0.001M DPPC in ACN:H2O and ACN:(0.1%TFA)H2O had been prepared based on literature. A 5μL droplet of DPPC remedy through the ACN/H2O remedy was noticed onto a pre-cleaned Si wafer for work with a DPPC research. 2.5 μL aliquots of DPPC solutions had been mixed 5 μL of corresponding DHB or DHB with TFA solutions then noticed onto wafers. A complete of 3 spectra from as much unique factors across each test had been collected. D2O movies D2O was integrated in to the model program through a drip valve. D2O was purified by 5 freeze-pump-thaw cycles. The leak valve was installed in another chamber from the mass spectrometer that is linked to the evaluation chamber by way of a butterfly valve. Foundation pressure within the chamber GFAP was 2×10-9torr typically. Using the pressure be opened Kobe0065 from the drip valve was adjusted to 1×10-7torr. An example pre-cooled to 90K of either DPPC or PHE was subjected to D2O while static SIMS spectra had been constantly being acquired. After the D2O+ sign reached exactly the same strength as [M+H]+ ion sign from DPPC or PHE the drip valve and valve between your chambers was shut as well as the vacuum program permitted to equilibrate. Film characterization Film thicknesses had been supervised with atomic-force microscopy (AFM) profilometery on the Nanopics 2100 AFM profilometer (KLA Tencor Milpitas CA). Crater thicknesses of DPPC and PHE movies had been recorded. Nevertheless thicknesses of DHB movies could not become accurately documented since DHB easily sublimes at space temp under UHV circumstances. SIMS Depth and characterization Information All depth profile analyses were collected in 90K. Static SIMS depth and spectra profiles were documented about a Bio-ToF mass spectrometer previously defined. A 20 keV C60+ resource (Ionoptika IOG-C60 Warrior Recreation area Britain) was used for sputtering and evaluation. Depth account spectra had been from a 200×200 μm2 evaluation region inside a 350×350 μm2 etch region. The principal ion beam measured 100-300 pA in DC mode typically. For evaluation a 60 ns pulse-width beam having a repetition price of 3 kHz was utilized to get the 100 0 summed spectra per routine. Results and dialogue Reference Samples Within the reference spectra evaluating DPPC sign with and without used matrix just a weak.