Identification and separation of protein, contaminant and substrate peaks using gentle‐secondary ion mass spectrometry and the <i>g</i>‐ogram

Interpretation of time-of-flight (TOF)-SIMS spectra of organic molecules could be difficult because of the presence of a high number of secondary ion peaks; this often requires the use of data analysis methods to simplify the TOF-SIMS measurements. In this study, we will demonstrate that the gentle-SIMS method could be applied to more easily interpret the TOF-SIMS spectra of organic solar cell materials. Various conditions of the primary ion beam were used to generate the gentle-SIMS spectra from pure layers of two materials, i.e. PC 70 BM and PCDTBT. It will be shown that by using specific conditions of the primary ion column, the corresponding molecular ion or characteristic peaks of the pure organic materials are highlighted. Results obtained on an organic layer prepared from a mixture of both materials will be also discussed.

Section: Resultsmentioning

confidence: 99%

G‐SIMS analysis of organic solar cell materials

Franquet

Fleischmann

Conard

et al. 2014

“…Although ToF‐SIMS is capable for obtaining surface chemical information, ToF‐SIMS data is so intricate that it is difficult to find out appropriate secondary ions for chemical imaging or those only specific to Aβ. Therefore, multivariate analysis such as principal component analysis (PCA) and spectrum analysis such as G‐SIMS and g‐ogram have been applied to ToF‐SIMS data in the previous study . In this study, PCA results were compared in detail in order to find the surface differences of Aβ regarding amino acid residues depending on the lipid.…”

Section: Introductionmentioning

confidence: 99%

The structural evaluation of amyloid beta on lipid membranes

Aoyagi¹,

Iwamura

Shimanouchi

et al. 2016

Self Cite

Amyloid beta (Aβ) adsorption onto lipid membranes depending on the condition of a lipid was investigated by means of time-offlight secondary ion mass spectrometry (ToF-SIMS). Aβ aggregation depending on the different hardness of lipid membrane has not been clarified yet although it is important to understand Alzheimer's disease. Aβ (1-40) on three different lipid membranes having different transition temperatures has been evaluated using ToF-SIMS in the previous study, and in this study, the differences between Aβ on liquid crystalline-phase lipid membranes and that on gel-phase lipid membranes were investigated in order to clarify the mechanisms of aggregation and peptide folding change. ToF-SIMS secondary ion images clearly showed Aβ distribution on lipid membranes. Because ToF-SIMS data is extremely complicated although it contains rich information, it was analysed by principal component analysis (PCA). Score images indicated by PCA are consistent with the images of secondary ions related to Aβ and are clearer than the secondary ion images. Moreover, PCA results suggest the difference between Aβ on different lipid membranes in terms of amino acid fragment ions, and the orientation of Aβ on 1,2-dipalmitoyl-sn-glycero-3-phosphocholine was indicated.

“…In addition, if it worked well, it is possible to extract the useful information which could not be understood without using it. Gentle‐SIMS (G‐SIMS) and g‐ogram were developed by National Physical Laboratory to interpret Static‐SIMS spectra more effectively. The information about the original chemical structure of a certain secondary ion and the relationships between fragment ions can be obtained by using those methods.…”

Section: Introductionmentioning

confidence: 99%

Evaluation and comparison of layered titanate nanosheets using TOF‐SIMS and g‐ogram analysis

Mihara

Nakagawa

Kudo

et al. 2015

Self Cite

The evaluation of nanostructure is important to develop the highly controlled nanomaterials. In this study, two kinds of layered titanate nanosheets, which were produced by using hexylamine and laurylamine, respectively, as surfactants were investigated by Gentle Secondary Ion Mass Spectrometry Gentle-SIMS (G-SIMS) and g-ogram, which is the latest Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) data analysis method for detecting more intact ions and obtaining the information on original chemical structures of samples precisely from complicated TOF-SIMS spectra. As a result, molecular related ions of the surfactants were detected from each sample, and the structural information of samples was obtained. From both samples, surfactant molecular ions connected with hydrocarbon were detected as more intact ions rather than molecular ions of themselves. It was suggested that hydrophobic domains of their lamellar mesostructure are formed robustly by more than two surfactant molecules connected with each other linearly. After all, important information on the chemical structure of the layered titanate nanosheets, which would be difficult to be found by using typical structural analysis methods such as X-ray diffraction and transmission electron microscopy, were obtained using G-SIMS and g-ogram. Therefore, it was shown that g-ogram and G-SIMS are helpful to evaluate the nanostructured materials. And it was also shown that g-ogram is applicable to organic-inorganic materials which contain long hydrocarbon structures.