1
|
Ji X, Challis JK, Brinkmann M. A critical review of diffusive gradients in thin films technique for measuring organic pollutants: Potential limitations, application to solid phases, and combination with bioassays. CHEMOSPHERE 2022; 287:132352. [PMID: 34826958 DOI: 10.1016/j.chemosphere.2021.132352] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Diffusive gradient in thin films (DGT) for organics has received considerable attention for studying the chemical dynamics of various organic pollutants in the environment. This review investigates current limitations of DGT for organics and identifies several research gaps for future studies. The application of a protective outer filter membrane has been recommended for most DGT applications, however, important questions regarding longer lag times due to significant interaction or adsorption of specific groups of compounds on the outer membrane remain. A modified DGT configuration has been developed that uses the diffusive gel as the outer membrane without the use of an extra filter membrane, however use of this configuration, while largely successful, remains limited. Biofouling has been a concern when using DGT for metals; however, effect on the performance of DGT for organics needs to be systemically studied. Storage stability of compounds on intact DGT samplers has been assessed in select studies and that data is synthesized here. DGT has been used to describe the kinetic desorption of antibiotics from soils and biosolids based on the soil/biosolid physical-chemical characteristics, yet applications remain limited and requires further research before wide-scale adoption is recommended. Finally, DGT for organics has been rarely, albeit successfully, combined with bioassays as well as in vivo bioaccumulation studies in zebrafish. Studies using DGT combined with bioassays to predict the adverse effects of environmental mixtures on aquatic or terrestrial biota are discussed here and should be considered for future research.
Collapse
Affiliation(s)
- Xiaowen Ji
- School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Canada; Global Institute for Water Security, University of Saskatchewan, Saskatoon, Canada
| | | | - Markus Brinkmann
- School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Canada; Global Institute for Water Security, University of Saskatchewan, Saskatoon, Canada; Toxicology Centre, University of Saskatchewan, Saskatoon, Canada; Centre for Hydrology, University of Saskatchewan, Saskatoon, Canada.
| |
Collapse
|
2
|
Martínez-Pérez P, García-Rupérez J. Commercial polycarbonate track-etched membranes as substrates for low-cost optical sensors. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2019; 10:677-683. [PMID: 30931209 PMCID: PMC6423561 DOI: 10.3762/bjnano.10.67] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 02/14/2019] [Indexed: 05/21/2023]
Abstract
Porous materials have become one of the best options for the development of optical sensors, since they maximize the interaction between the optical field and the target substances, which boosts the sensitivity. In this work, we propose the use of a readily available mesoporous material for the development of such sensors: commercial polycarbonate track-etched membranes. In order to demonstrate their utility for this purpose, we firstly characterized their optical response in the near-infrared range. This response is an interference fringe pattern, characteristic of a Fabry-Pérot interferometer, which is an optical device typically used for sensing purposes. Afterwards, several refractive index sensing experiments were performed by placing different concentrations of ethanol solution on the polycarbonate track-etched membranes. As a result, a sensitivity value of around 56 nm/RIU was obtained and the reusability of the substrate was demonstrated. These results pave the way for the development of optical porous sensors with such easily available mesoporous material.
Collapse
Affiliation(s)
- Paula Martínez-Pérez
- Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Jaime García-Rupérez
- Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| |
Collapse
|
3
|
Knorr RL, Steinkühler J, Dimova R. Micron-sized domains in quasi single-component giant vesicles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1957-1964. [DOI: 10.1016/j.bbamem.2018.06.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 06/25/2018] [Accepted: 06/26/2018] [Indexed: 12/29/2022]
|
4
|
Shindell O, Mica N, Cheng KH, Wang E, Gordon VD. Dynamic Fingering in Adhered Lipid Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:4673-4680. [PMID: 29363972 DOI: 10.1021/acs.langmuir.7b03708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Artificial lipid membranes incorporating proteins have frequently been used as models for the dynamic organization of biological structures in living cells as well as in the development of biology-inspired technologies. We report here on the experimental demonstration and characterization of a pattern-forming process that occurs in a lipid bilayer membrane adhered via biotin-avidin binding to a second lipid membrane that is supported by a solid substrate. Adhesion regions are roughly circular with a diameter of about 25 μm. Using confocal fluorescence microscopy, we record time series of dynamic fingering patterns that grow in the upper lipid membrane and intermembrane biotin-avidin bonds. The fingers are micrometer-scale elongated pores that grow from the edge of an already-stabilized hole. Finger growth is saltatory on the scale of tens of seconds. We find that as the fingers grow and the density of adhesion proteins increases, the rate of finger growth decreases exponentially and the width of newly formed fingers decreases linearly. We show that these findings are consistent with a thermodynamic description of dynamic pore formation and stabilization.
Collapse
Affiliation(s)
- Orrin Shindell
- Center for Nonlinear Dynamics and Department of Physics , University of Texas at Austin , Austin 78712 , United States
- Department of Physics and Astronomy , Trinity University , San Antonio , Texas 78212 , United States
| | - Natalie Mica
- Center for Nonlinear Dynamics and Department of Physics , University of Texas at Austin , Austin 78712 , United States
- School of Physics and Astronomy , University of St. Andrews , Saint Andrews , Scotland KY16 9AJ , U.K
| | - Kwan H Cheng
- Department of Physics and Astronomy , Trinity University , San Antonio , Texas 78212 , United States
| | - Exing Wang
- Department of Cell Systems & Anatomy , University of Texas Health Science Center San Antonio , San Antonio , Texas 78229 , United States
| | - Vernita D Gordon
- Center for Nonlinear Dynamics and Department of Physics , University of Texas at Austin , Austin 78712 , United States
| |
Collapse
|
5
|
Gleisner M, Kroppen B, Fricke C, Teske N, Kliesch TT, Janshoff A, Meinecke M, Steinem C. Epsin N-terminal Homology Domain (ENTH) Activity as a Function of Membrane Tension. J Biol Chem 2016; 291:19953-61. [PMID: 27466364 DOI: 10.1074/jbc.m116.731612] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Indexed: 12/18/2022] Open
Abstract
The epsin N-terminal homology domain (ENTH) is a major player in clathrin-mediated endocytosis. To investigate the influence of initial membrane tension on ENTH binding and activity, we established a bilayer system based on adhered giant unilamellar vesicles (GUVs) to be able to control and adjust the membrane tension σ covering a broad regime. The shape of each individual adhered GUV as well as its adhesion area was monitored by spinning disc confocal laser microscopy. Control of σ in a range of 0.08-1.02 mN/m was achieved by altering the Mg(2+) concentration in solution, which changes the surface adhesion energy per unit area of the GUVs. Specific binding of ENTH to phosphatidylinositol 4,5-bisphosphate leads to a substantial increase in adhesion area of the sessile GUV. At low tension (<0.1 mN/m) binding of ENTH can induce tubular structures, whereas at higher membrane tension the ENTH interaction deflates the sessile GUV and thereby increases the adhesion area. The increase in adhesion area is mainly attributed to a decrease in the area compressibility modulus KA We propose that the insertion of the ENTH helix-0 into the membrane is largely responsible for the observed decrease in KA, which is supported by the observation that the mutant ENTH L6E shows a reduced increase in adhesion area. These results demonstrate that even in the absence of tubule formation, the area compressibility modulus and, as such, the bending rigidity of the membrane is considerably reduced upon ENTH binding. This renders membrane bending and tubule formation energetically less costly.
Collapse
Affiliation(s)
- Martin Gleisner
- From the Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany
| | - Benjamin Kroppen
- Department of Cellular Biochemistry, University of Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Christian Fricke
- From the Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany
| | - Nelli Teske
- From the Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany
| | - Torben-Tobias Kliesch
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany, and
| | - Andreas Janshoff
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany, and Göttingen Center for Molecular Biosciences, 37077 Göttingen, Germany
| | - Michael Meinecke
- Department of Cellular Biochemistry, University of Göttingen, Humboldtallee 23, 37073 Göttingen, Germany, European Neuroscience Institute, 37073 Göttingen, Germany,
| | - Claudia Steinem
- From the Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany, Göttingen Center for Molecular Biosciences, 37077 Göttingen, Germany
| |
Collapse
|
6
|
Gordon VD, O'Halloran TJ, Shindell O. Membrane adhesion and the formation of heterogeneities: biology, biophysics, and biotechnology. Phys Chem Chem Phys 2015; 17:15522-33. [PMID: 25866854 PMCID: PMC4465551 DOI: 10.1039/c4cp05876c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Membrane adhesion is essential to many vital biological processes. Sites of membrane adhesion are often associated with heterogeneities in the lipid and protein composition of the membrane. These heterogeneities are thought to play functional roles by facilitating interactions between proteins. However, the causal links between membrane adhesion and membrane heterogeneities are not known. Here we survey the state of the field and indicate what we think are understudied areas ripe for development.
Collapse
Affiliation(s)
- V D Gordon
- The University of Texas at Austin, Department of Physics and Center for Nonlinear Dynamics, 2515 Speedway, Stop C1610, Austin, Texas 78712-1199, USA.
| | | | | |
Collapse
|