| 1. |
- Ali Doosti, Baharan, 1991, et al.
(författare)
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Generation of interconnected vesicles in a liposomal cell model
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- We introduce an experimental method based upon a glass micropipette microinjection technique for generating a multitude of interconnected vesicles (IVs) in the interior of a single giant unilamellar phospholipid vesicle (GUV) serving as a cell model system. The GUV membrane, consisting of a mixture of soybean polar lipid extract and anionic phosphatidylserine, is adhered to a multilamellar lipid vesicle that functions as a lipid reservoir. Continuous IV formation was achieved by bringing a micropipette in direct contact with the outer GUV surface and subjecting it to a localized stream of a Ca2+ solution from the micropipette tip. IVs are rapidly and sequentially generated and inserted into the GUV interior and encapsulate portions of the micropipette fluid content. The IVs remain connected to the GUV membrane and are interlinked by short lipid nanotubes and resemble beads on a string. The vesicle chain-growth from the GUV membrane is maintained for as long as there is the supply of membrane material and Ca2+ solution, and the size of the individual IVs is controlled by the diameter of the micropipette tip. We also demonstrate that the IVs can be co-loaded with high concentrations of neurotransmitter and protein molecules and displaying a steep calcium ion concentration gradient across the membrane. These characteristics are analogous to native secretory vesicles and could, therefore, serve as a model system for studying secretory mechanisms in biological systems.
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| 2. |
- Athanasiou, Vasileios, 1988, et al.
(författare)
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On Sensing Principles Using Temporally Extended Bar Codes
- 2020
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Ingår i: IEEE Sensors Journal. - 1558-1748 .- 1530-437X. ; 20:13, s. 6782-6791
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Tidskriftsartikel (refereegranskat)abstract
- The detection of ionic variation patterns could be a significant marker for the diagnosis of neurological and other diseases. This paper introduces a novel idea for training chemical sensors to recognise patterns of ionic variations. By using an external voltage signal, a sensor can be trained to output distinct time-series signals depending on the state of the ionic solution. Those sequences can be analysed by a relatively simple readout layer for diagnostic purposes. The idea is demonstrated on a chemical sensor that is sensitive to zinc ions with a simple goal of classifying zinc ionic variations as either stable or varying. The study features both theoretical and experimental results. By extensive numerical simulations, it has been shown that the proposed method works successfully in silico. Distinct time-series signals are found which occur with a high probability under only one class of ionic variations. The related experimental results point in the right direction.
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| 3. |
- Gözen, Irep, 1980, et al.
(författare)
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Protocells: Milestones and Recent Advances
- 2022
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Ingår i: Small. - : Wiley. - 1613-6810 .- 1613-6829. ; 18:18
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Forskningsöversikt (refereegranskat)abstract
- The origin of life is still one of humankind's great mysteries. At the transition between nonliving and living matter, protocells, initially featureless aggregates of abiotic matter, gain the structure and functions necessary to fulfill the criteria of life. Research addressing protocells as a central element in this transition is diverse and increasingly interdisciplinary. The authors review current protocell concepts and research directions, address milestones, challenges and existing hypotheses in the context of conditions on the early Earth, and provide a concise overview of current protocell research methods.
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| 4. |
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| 5. |
- Meng, Fanda, 1987, et al.
(författare)
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A tandem giant magnetoresistance assay for one-shot quantification of clinically relevant concentrations of N-terminal pro-B-type natriuretic peptide in human blood
- 2021
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 413:11, s. 2943-2949
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Tidskriftsartikel (refereegranskat)abstract
- We report a microfluidic sandwich immunoassay constructed around a dual-giant magnetoresistance (GMR) sensor array to quantify the heart failure biomarker NT-proBNP in human plasma at the clinically relevant concentration levels between 15 pg/mL and 40 ng/mL. The broad dynamic range was achieved by differential coating of two identical GMR sensors operated in tandem, and combining two standard curves. The detection limit was determined as 5 pg/mL. The assay, involving 53 plasma samples from patients with different cardiovascular diseases, was validated against the Roche Cobas e411 analyzer. The salient features of this system are its wide concentration range, low detection limit, small sample volume requirement (50 μL), and the need for a short measurement time of 15 min, making it a prospective candidate for practical use in point of care analysis.
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| 6. |
- Meng, Fanda, 1987, et al.
(författare)
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Dynamic Range Expansion of the C-Reactive Protein Quantification with a Tandem Giant Magnetoresistance Biosensor
- 2021
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Ingår i: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 6:19, s. 12923-12930
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we report a convenient analytical method for a full-range quantification of the C-reactive protein (CRP), a blood biomarker of infection and cardiovascular events. We determine CRP over the entire diagnostically relevant concentration range in undiluted human blood serum in a single test, using a tandem giant magnetoresistance (GMR) sensor. The tandem principle combines a sandwich assay and a competitive assay, which allows for the discrimination of the concentration values resulting from the multivalued dose-response curve ("Hook"effect), which characterizes the one-step sandwich assay at high CRP concentrations. The sensor covers a linear detection range for CRP concentration from 3 ng/mL to 350 μg/mL, the detection limit (s/n = 3) is 1 ng/mL. The prominent features of the chip-based method are its expanded dynamic range and low sample volume (50 μL), and the need for a short measurement time of 15 min. These figures of merit, in addition to the low detection limit equal to the established assay instrumentation, make it a viable candidate for use in point-of-care diagnostics.
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| 7. |
- Spustova, Karolina, et al.
(författare)
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Manipulation of Lipid Membranes with Thermal Stimuli
- 2022
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Ingår i: Methods in Molecular Biology. - New York, NY : Springer US. - 1940-6029 .- 1064-3745. ; , s. 209-225
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- We describe a protocol for the assembly and application of infrared (IR-B) laser-based set-ups to be used for localized heating of solid-supported planar and vesicular lipid membrane assemblies.
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