| 1. |
- Cárdenas, Marité, et al.
(författare)
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Review of structural design guiding the development of lipid nanoparticles for nucleic acid delivery
- 2023
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Ingår i: Current Opinion in Colloid and Interface Science. - : Elsevier. - 1359-0294 .- 1879-0399. ; 66
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Forskningsöversikt (refereegranskat)abstract
- Lipid nanoparticles (LNPs) are the most versatile and successful gene delivery systems, notably highlighted by their use in vaccines against COVID-19. LNPs have a well-defined core–shell structure, each region with its own distinctive compositions, suited for a wide range of in vivo delivery applications. Here, we discuss how a detailed knowledge of LNP structure can guide LNP formulation to improve the efficiency of delivery of their nucleic acid payload. Perspectives are detailed on how LNP structural design can guide more efficient nucleic acid transfection. Views on key physical characterization techniques needed for such developments are outlined including opinions on biophysical approaches both correlating structure with functionality in biological fluids and improving their ability to escape the endosome and deliver they payload.
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| 2. |
- Jarrett, K. J., et al.
(författare)
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The spatial modulation of microfibril angle in the woody tissue of maturing tree stems studied with synchrotron radiation
- 2020
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Ingår i: Australian Journal of Botany. - : CSIRO Publishing. - 0067-1924 .- 1444-9862. ; 68:4, s. 267-274
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Tidskriftsartikel (refereegranskat)abstract
- Spatial variations in the microfibril angle (MFA) of cellulose are mapped on individual radial sections of wood from the maturing stems of Australian tree species (Acacia floribunda, Acacia suaveolens, Acacia doratoxylon, Acacia havilandiorum, Brachychiton populneus and Bertya cunninghamii) from different rainfall and soil nutrient availabilities using synchrotron wide angle X-ray scattering. For the three species with the smallest radial variation there is a clear linear relationship between the MFA with Young's modulus and wood density with data published previously for these samples. The other three samples show a large radially symmetric variation in MFA across the radial section either having a continuous change from large MFA in the stem's centre to small value close to the bark or the reverse, small MFA at the centre to larger values close to the bark. For these samples, a strong linear correlation between the Young's modulus and density and the MFA is not apparent. We conclude that spatially localised measurements of MFA provide an important insight in the adaptation of wood tissue to environmental conditions.
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| 3. |
- Robertsson, Carolina, 1993-
(författare)
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Responses to External Cues in Oral Bacteria
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigates responses to external cues in oral bacteria on a molecular level. Paper I maps Ser/Thr/Tyr phosphorylated proteins in relation to the general proteome in an oral commensal streptococcus (Streptococcus gordonii DL1). The identified phosphoproteins were involved in various bacterial processes, several associated to dysbiosis and development of biofilm-induced disease. Comparison against phosphoproteomes of other bacteria showed many similarities. This is of interest for the identification of shared phosphorylation profiles. Paper II studies differences between the S. gordonii DL1 general proteomes in planktonic and biofilm growth phases, and the regulatory effects of salivary mucin MUC5B on protein expression in the biofilm cells. Regulations in protein expression between the different growth conditions provides insights in bacterial mechanisms for adaptation to the biofilm lifestyle. Paper III examines the regulatory roles of salivary MUC5B on biofilm attachment and metabolic output in two clinical isolates of oral commensals, S. gordonii CW and Actinomyces naeslundii CW. S. gordonii facilitated adhesion of A. naeslundii to MUC5B during early attachment. Both bacteria were also able to utilize MUC5B as a sole nutrient source during early biofilm formation, individually and synergistically in a dual species biofilm. The specific responses elicited by MUC5B in paper II-III seem to promote commensal colonization while down-regulating dysbiosis-related biofilm activities. Microbiological studies are often focused on dysbiosis and development of disease. However, mechanisms that promote eubiosis are equally important to understand how health can be maintained. Findings associated with responses to external cues in oral bacteria may contribute to future development of novel preventative strategies and identification of predictive biomarkers for oral health.
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| 4. |
- Aleksejeva, Olga, et al.
(författare)
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Dual-feature photobioanodes based on nanoimprint lithography for photoelectric biosupercapacitors
- 2022
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Ingår i: Journal of Power Sources. - : Elsevier. - 0378-7753 .- 1873-2755. ; 517
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Tidskriftsartikel (refereegranskat)abstract
- Direct transformation of solar energy into electrical energy by means of biological photosynthesis is considered as an attractive option for sustainable electrical energy production. Thylakoid membranes, the site of photosynthesis, are regarded as a promising biological material for the development of photoelectric biodevices, which produce electrical power consuming only light energy as oxygen evolves at photobioanode upon irradiation and biocathode converts it back to water. Therefore, in this work dual-feature photobioanode based on nanoimprinted gold substrates modified with thylakoids in combination with a capacitive part made of a planar gold substrate coated with a conductive polymer was designed and evaluated, providing open-circuit potential of -0.21 V vs. Ag vertical bar AgCl vertical bar KClsat and a capacitance of ca. 60 F m(-2) both at ambient light and artificial illumination of 400 W m(-2). Combination of thylakoid based dual-feature photobioanode with bilirubin oxidase modified transparent and capacitive indium tin oxide biocathode resulted in a photoelectric biosupercapacitor with remarkable characteristics at ambient light, viz. an open-circuit voltage as high as 0.74 V, which was stable upon charge-discharge cycles during ca. 2 h.
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| 5. |
- Beck, Christian, et al.
(författare)
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Short-Time Transport Properties of Bidisperse Suspensions of Immunoglobulins and Serum Albumins Consistent with a Colloid Physics Picture.
- 2022
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Ingår i: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1520-6106 .- 1520-5207. ; 126:38, s. 7400-7408
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Tidskriftsartikel (refereegranskat)abstract
- The crowded environment of biological systems such as the interior of living cells is occupied by macromolecules with a broad size distribution. This situation of polydispersity might influence the dependence of the diffusive dynamics of a given tracer macromolecule in a monodisperse solution on its hydrodynamic size and on the volume fraction. The resulting size dependence of diffusive transport crucially influences the function of a living cell. Here, we investigate a simplified model system consisting of two constituents in aqueous solution, namely, of the proteins bovine serum albumin (BSA) and bovine polyclonal gamma-globulin (Ig), systematically depending on the total volume fraction and ratio of these constituents. From high-resolution quasi-elastic neutron spectroscopy, the separate apparent short-time diffusion coefficients for BSA and Ig in the mixture are extracted, which show substantial deviations from the diffusion coefficients measured in monodisperse solutions at the same total volume fraction. These deviations can be modeled quantitatively using results from the short-time rotational and translational diffusion in a two-component hard sphere system with two distinct, effective hydrodynamic radii. Thus, we find that a simple colloid picture well describes short-time diffusion in binary mixtures as a function of the mixing ratio and the total volume fraction. Notably, the self-diffusion of the smaller protein BSA in the mixture is faster than the diffusion in a pure BSA solution, whereas the self-diffusion of Ig in the mixture is slower than in the pure Ig solution.
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| 6. |
- Beyer, Sarah, 1982-, et al.
(författare)
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Fluorescent Molecularly Imprinted Polymer Layers against Sialic Acid on Silica-Coated Polystyrene Cores — Assessment of the Binding Behavior to Cancer Cells
- 2022
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Ingår i: Cancers. - : MDPI. - 2072-6694. ; 14:8
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Tidskriftsartikel (refereegranskat)abstract
- Sialic acid (SA) is a monosaccharide usually linked to the terminus of glycan chains on the cell surface. It plays a crucial role in many biological processes, and hypersialylation is a common feature in cancer. Lectins are widely used to analyze the cell surface expression of SA. However, these protein molecules are usually expensive and easily denatured, which calls for the development of alternative glycan-specific receptors and cell imaging technologies. In this study, SA-imprinted fluorescent core-shell molecularly imprinted polymer particles (SA-MIPs) were employed to recognize SA on the cell surface of cancer cell lines. The SA-MIPs improved suspensibility and scattering properties compared with previously used core-shell SA-MIPs. Although SA-imprinting was performed using SA without preference for the α2,3-and α2,6-SA forms, we screened the cancer cell lines analyzed using the lectins Maackia Amurensis Lectin I (MAL I, α2,3-SA) and Sambucus Nigra Lectin (SNA, α2,6-SA). Our results show that the selected cancer cell lines in this study presented a varied binding behavior with the SA-MIPs. The binding pattern of the lectins was also demonstrated. Moreover, two different pentavalent SA conjugates were used to inhibit the binding of the SA-MIPs to breast, skin, and lung cancer cell lines, demonstrating the specificity of the SA-MIPs in both flow cytometry and confocal fluorescence microscopy. We concluded that the synthesized SA-MIPs might be a powerful future tool in the diagnostic analysis of various cancer cells.
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| 7. |
- Buchanan, Claire, et al.
(författare)
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Comprehensive multidimensional study of the self-assembly properties of a three residue substituted beta(3) oligoamide
- 2021
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Ingår i: Pure and Applied Chemistry. - : Walter de Gruyter. - 0033-4545 .- 1365-3075. ; 93:11, s. 1327-1341
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Tidskriftsartikel (refereegranskat)abstract
- Substituted (beta(3) oligoamides form a unique self-assembling system where each monomer folds into a helix containing approximately three (beta(3) amino acids per turn, yielding a geometrically well-defined cylindrical building block that, when N-acylated, is able to self-assemble head-to-tail into nanorods that can reach several 100 mu m length. It was shown in previous works that self-assembly can be achieved with a three residue long oligoamide as well that lacks any intramolecular H-bonds, yet it crystallizes in a helix-like conformation. The self-assembly properties of these small oligoamides are however elusive, suggesting a more complex system than the self-assembly of the H-bond stabilized helical monomers. Here we focus on the self-assembly behaviour of a three residue oligoamide, Ac-beta(3)[LIA] where the letters denote the side chain of the analogous a amino acid. Ac-beta(3)[LIA] can yield highly inhomogeneous suspensions in water with a broad range of large fibrous structures that seem to be very stable, yet occasionally fibre growth is only observed upon heating. The small size of the monomer suggests a highly dynamic equilibrium yet all previous attempts failed to clearly identify low molecular weight species. Therefore a special methodology was employed in this study to characterize the suspensions at different size ranges: SANS that is optimal to measure the small oligomers and cross sectional diameter of the assemblies, DLS that is sensitive to the large populations and therefore the length of the superstructures, and NMR that is sensitive to monomeric and small oligomeric form, in conjunction with IR spectroscopy to probe the folding and AFM to image the morphology of the assemblies. Temperature ramping was used to perturb the system to probe the dynamicity of the self-assembly. It was found that the anomalous self-assembly behaviour of Ac-beta(3)[LIA] is caused by its two stable conformations, a helix-building "horseshoe" fold and a linear conformer. The latter is exclusively found in monomeric form in solution whereas the horseshoe fold is stable in solid phase and in fibrous assemblies. Small oligomers were absent. Thus the self assembly of Ac-beta(3)[LIA] is arrested by the activation energy need of the conformation change; fibre growth might be triggered by conditions that allow increased conformational freedom of the monomers. This observation may be used to develop strategies for controlled switchable self-assembly.
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| 8. |
- Buchanan, Claire, et al.
(författare)
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Coordination crosslinking of helical substituted oligoamide nanorods with Cu(II)
- 2020
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Ingår i: Supramolecular Chemistry. - : Informa UK Limited. - 1061-0278 .- 1029-0478. ; 32:3, s. 222-232
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Tidskriftsartikel (refereegranskat)abstract
- Substituted oligoamides are short sequences of unnatural amino acids. Oligoamides made entirely of β3 amino acids yield helical monomers that, if N-acylated, assemble into nanorod structures via a supramolecular assembly motif. In this work, coordination crosslinking was used to create complex nanomaterials from oligoamides WKLWEL (KE) and WELWEL (EE) (the letters denote the analogous α-amino acids). Upon Cu(II) addition, atomic force microscopy and small angle neutron scattering revealed morphologic changes specific to KE but absent in EE. Vibration spectroscopy measurements revealed that Cu(II) can coordinate to the amine moieties of the side chains, without direct effect on the backbone amides. While coordination in excess solvent lead to regular nanostructures, fast drying of the sample yielded oligoamide templated crystallization of CuCl2. The metal coordination crosslinking of supramolecular assemblies as reported here is the first realization of a metallosupramolecular framework structure.
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| 9. |
- Cabaleiro-Lago, Celia, et al.
(författare)
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Recent Advances in Molecularly Imprinted Polymers and Their Disease-Related Applications
- 2023
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Ingår i: Polymers. - : MDPI. - 2073-4360. ; 15:21, s. 4199-4199
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Forskningsöversikt (refereegranskat)abstract
- Molecularly imprinted polymers (MIPs) and the imprinting technique provide polymeric material with recognition elements similar to natural antibodies. The template of choice (i.e., the antigen) can be almost any type of smaller or larger molecule, protein, or even tissue. There are various formats of MIPs developed for different medical purposes, such as targeting, imaging, assay diagnostics, and biomarker detection. Biologically applied MIPs are widely used and currently developed for medical applications, and targeting the antigen with MIPs can also help in personalized medicine. The synthetic recognition sites of the MIPs can be tailor-made to function as analytics, diagnostics, and drug delivery systems. This review will cover the promising clinical applications of different MIP systems recently developed for disease diagnosis and treatment.
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| 10. |
- Contardi, Cecilia, et al.
(författare)
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Affinity Capillary Electrophoresis as a Tool To Characterize Molecularly Imprinted Nanogels in Solution
- 2024
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 96:7, s. 3017-3024
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Tidskriftsartikel (refereegranskat)abstract
- In this work, an innovative and accurate affinity capillary electrophoresis (ACE) method was set up to monitor the complexation of aqueous MIP nanogels (NGs) with model cancer-related antigens. Using α2,6′- and α2,3′-sialyllactose as oversimplified cancer biomarker-mimicking templates, NGs were synthesized and characterized in terms of size, polydispersity, and overall charge. A stability study was also carried out in order to select the best storage conditions and to ensure product quality. After optimization of capillary electrophoresis conditions, injection of MIP NGs resulted in a single, sharp, and efficient peak. The mobility shift approach was applied to quantitatively estimate binding affinity, in this case resulting in an association constant of K ≈ 106 M–1. The optimized polymers further displayed a pronounced discrimination between the two sialylated sugars. The newly developed ACE protocol has the potential to become a very effective method for nonconstrained affinity screening of NG in solution, especially during the NG development phase and/or for a final accurate quantitation of the observed binding.
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