Oil-Free Gold Nanobipyramid@Ag Microgels as a Functional SERS Substrate for Direct Detection of Small Molecules in a Complex Sample Matrix

Yeast tolerates a low pH and high solvent concentrations. The permeability of the plasma membrane (PM) for small molecules is low and lateral diffusion of proteins is slow. These findings suggest a high degree of lipid order, which raises the question of how membrane proteins function in such an environment. The yeast PM is segregated into the Micro-Compartment-of-Can1 (MCC) and Pma1 (MCP), which have different lipid compositions. We extracted proteins from these microdomains via stoichiometric capture of lipids and proteins in styrene-maleic-acid-lipid-particles (SMALPs). We purified SMALP-lipid-protein complexes by chromatography and quantitatively analyzed periprotein lipids located within the diameter defined by one SMALP. Phospholipid and sterol concentrations are similar for MCC and MCP, but sphingolipids are enriched in MCP. Ergosterol is depleted from this periprotein lipidome, whereas phosphatidylserine is enriched relative to the bulk of the plasma membrane. Direct detection of PM lipids in the 'periprotein space' supports the conclusion that proteins function in the presence of a locally disordered lipid state.

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Quantification of Fructans in Bioethanol Stillage Based On a Simplified Analytical Method

10.21203/rs.3.rs-507266/v1 ◽

2021 ◽

Author(s):

Andreas Zimmermann ◽

Martin Kaltschmitt

Keyword(s):

Analytical Method ◽

Measurement Errors ◽

Process Development ◽

Stationary Phases ◽

New Approach ◽

Sample Matrix ◽

Sample Throughput ◽

Complex Sample ◽

Potential Substrate

Abstract Bioethanol stillage, the main by-product of industrial bioethanol production, is a potential substrate for fructans. However, the determination and quantification of fructans in such complex sample matrices is still a challenge for the corresponding analytics to be overcome in order to allow for the identification and utilisation of such unused fructan sources. Especially a possible utilisation or rather the corresponding process development requires appropriate analytics first. Thus, this paper aims to illuminate the basics of fructan quantification in stillage and the corresponding challenges particularly arising with widely used HPLC-RID systems. On this basis, a new approach for fructan quantification is presented based on such HPLC-RID systems allowing for a reliable and especially simple fructan determination in bioethanol stillage for comparably high sample throughput. The developed method performs fructan quantification by determination of fructose and glucose equivalents after a targeted acidic hydrolysis adapted to the respective sample matrix. By means of two different stationary phases, the problem of limited resolution in case of HPLC-RID is overcome and thus measurement errors are reduced. The approach towards the adapted analytical method can be transferred easily to comparable complex sample matrices.

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Identification of pyrene in complex sample matrix using time-resolved fluorescence measurement coupled with PARAFAC analysis

Journal of Photochemistry and Photobiology A Chemistry ◽

10.1016/j.jphotochem.2019.111991 ◽

2019 ◽

Vol 383 ◽

pp. 111991 ◽

Cited By ~ 1

Author(s):

Suraj Kumar Panigrahi ◽

Ashok Kumar Mishra

Keyword(s):

Fluorescence Measurement ◽

Time Resolved Fluorescence ◽

Time Resolved ◽

Sample Matrix ◽

Complex Sample

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Bioscaffold arrays decorated with Ag nanoparticles as a SERS substrate for direct detection of melamine in infant formula

RSC Advances ◽

10.1039/c9ra01862j ◽

2019 ◽

Vol 9 (38) ◽

pp. 21771-21776 ◽

Cited By ~ 4

Author(s):

Nan Zhao ◽

Hefu Li ◽

Cunwei Tian ◽

Yanru Xie ◽

Zhenbao Feng ◽

...

Keyword(s):

High Performance ◽

Direct Detection ◽

Three Dimensional ◽

Sers Substrate ◽

Sers Substrates ◽

Plasmonic Structures ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering ◽

Performance Surface

Three-dimensional (3D) plasmonic structures have been intensively investigated as high performance surface enhanced Raman scattering (SERS) substrates.

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Analytical techniques for metabolomic studies: a review

Bioanalysis ◽

10.4155/bio-2019-0014 ◽

2019 ◽

Vol 11 (24) ◽

pp. 2297-2318 ◽

Cited By ~ 16

Author(s):

Karen Segers ◽

Sven Declerck ◽

Debby Mangelings ◽

Yvan Vander Heyden ◽

Ann Van Eeckhaut

Keyword(s):

Physicochemical Properties ◽

Small Molecules ◽

Supercritical Fluid ◽

Small Molecule ◽

Supercritical Fluid Chromatography ◽

Analytical Techniques ◽

Separation Techniques ◽

Sample Matrix ◽

Comprehensive Study

Metabolomics is the comprehensive study of small-molecule metabolites. Obtaining a wide coverage of the metabolome is challenging because of the broad range of physicochemical properties of the small molecules. To study the compounds of interest spectroscopic (NMR), spectrometric (MS) and separation techniques (LC, GC, supercritical fluid chromatography, CE) are used. The choice for a given technique is influenced by the sample matrix, the concentration and properties of the metabolites, and the amount of sample. This review discusses the most commonly used analytical techniques for metabolomic studies, including their advantages, drawbacks and some applications.

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1,5-Diaminonaphthalene functionalized carbon nanodots as a novel matrix for the analysis of small molecules by matrix-assisted laser desorption/ionization mass spectrometry

Analytical Methods ◽

10.1039/c8ay02665c ◽

2019 ◽

Vol 11 (8) ◽

pp. 1131-1136 ◽

Cited By ~ 1

Author(s):

Yueying Zhang ◽

Dan Gao ◽

Shangfu Li ◽

Weili Wei ◽

Jinshun Lin ◽

...

Keyword(s):

Small Molecules ◽

Direct Detection ◽

Laser Desorption ◽

Negative Ion ◽

Carbon Nanodots ◽

Ionization Mass ◽

Laser Desorption Ionization ◽

Negative Ion Mode ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

1,5-Diaminonaphthalene functionalized carbon nanodots (DAN-CDs) were explored as a matrix for direct detection of small molecules by MALDI-MS in negative-ion mode.

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