1
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Berganza L, Litti L, Meneghetti M, Lanceros-Méndez S, Reguera J. Enhancement of Magnetic Surface-Enhanced Raman Scattering Detection by Tailoring Fe 3O 4@Au Nanorod Shell Thickness and Its Application in the On-site Detection of Antibiotics in Water. ACS OMEGA 2022; 7:45493-45503. [PMID: 36530269 PMCID: PMC9753213 DOI: 10.1021/acsomega.2c06099] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
Surface-enhanced Raman scattering (SERS) has become a promising method for the detection of contaminants or biomolecules in aqueous media. The low interference of water, the unique spectral fingerprint, and the development of portable and handheld equipment for in situ measurements underpin its predominance among other spectroscopic techniques. Among the SERS nanoparticle substrates, those composed of plasmonic and magnetic components are prominent examples of versatility and efficiency. These substrates harness the ability to capture the target analyte, concentrate it, and generate unique hotspots for superior enhancement. Here, we have evaluated the use of gold-coated magnetite nanorods as a novel multifunctional magnetic-plasmonic SERS substrate. The nanostructures were synthesized starting from core-satellite structures. A series of variants with different degrees of Au coatings were then prepared by seed-mediated growth of gold, from core-satellite structures to core-shell with partial and complete shells. All of them were tested, using a portable Raman instrument, with the model molecule 4-mercaptobenzoic acid in colloidal suspension and after magnetic separation. Experimental results were compared with the boundary element method to establish the mechanism of Raman enhancement. The results show a quick magnetic separation of the nanoparticles and excellent Raman enhancement for all the nanoparticles both in dispersion and magnetically concentrated with limits of detection up to the nM range (∼50 nM) and a quantitative calibration curve. The nanostructures were then tested for the sensing of the antibiotic ciprofloxacin, highly relevant in preventing antibiotic contaminants in water reservoirs and drug monitoring, showing that ciprofloxacin can be detected using a portable Raman instrument at a concentration as low as 100 nM in a few minutes, which makes it highly relevant in practical point-of-care devices and in situ use.
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Affiliation(s)
- Leixuri
B. Berganza
- BCMaterials,
Basque Center for Materials, Applications, and Nanostructures, UPV/EHU
Science Park, 48940Leioa, Spain
| | - Lucio Litti
- Nanostructures
and Optics Laboratory, Department of Chemical Sciences, University of Padova, Via Marzolo, 1, 35131Padova, Italy
| | - Moreno Meneghetti
- Nanostructures
and Optics Laboratory, Department of Chemical Sciences, University of Padova, Via Marzolo, 1, 35131Padova, Italy
| | - Senentxu Lanceros-Méndez
- BCMaterials,
Basque Center for Materials, Applications, and Nanostructures, UPV/EHU
Science Park, 48940Leioa, Spain
- Ikerbasque,
Basque Foundation for Science Bilbao, Plaza Euskadi 5, 48009Bilbao, Spain
| | - Javier Reguera
- BCMaterials,
Basque Center for Materials, Applications, and Nanostructures, UPV/EHU
Science Park, 48940Leioa, Spain
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2
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Cai L, Fang G, Tang J, Cheng Q, Han X. Label-Free Surface-Enhanced Raman Spectroscopic Analysis of Proteins: Advances and Applications. Int J Mol Sci 2022; 23:ijms232213868. [PMID: 36430342 PMCID: PMC9695365 DOI: 10.3390/ijms232213868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/05/2022] [Accepted: 11/07/2022] [Indexed: 11/12/2022] Open
Abstract
Surface-enhanced Raman spectroscopy (SERS) is powerful for structural characterization of biomolecules under physiological condition. Owing to its high sensitivity and selectivity, SERS is useful for probing intrinsic structural information of proteins and is attracting increasing attention in biophysics, bioanalytical chemistry, and biomedicine. This review starts with a brief introduction of SERS theories and SERS methodology of protein structural characterization. SERS-active materials, related synthetic approaches, and strategies for protein-material assemblies are outlined and discussed, followed by detailed discussion of SERS spectroscopy of proteins with and without cofactors. Recent applications and advances of protein SERS in biomarker detection, cell analysis, and pathogen discrimination are then highlighted, and the spectral reproducibility and limitations are critically discussed. The review ends with a conclusion and a discussion of current challenges and perspectives of promising directions.
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Affiliation(s)
- Linjun Cai
- National Engineering Laboratory for AIDS Vaccine, School of Life Science, Jilin University, Changchun 130012, China
- Correspondence: (L.C.); (X.H.)
| | - Guilin Fang
- National Engineering Laboratory for AIDS Vaccine, School of Life Science, Jilin University, Changchun 130012, China
| | - Jinpin Tang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Qiaomei Cheng
- National Engineering Laboratory for AIDS Vaccine, School of Life Science, Jilin University, Changchun 130012, China
| | - Xiaoxia Han
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
- Correspondence: (L.C.); (X.H.)
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3
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Zhang X, Bai J, Wang R, Wei X, Chen M, Yang T, Wang J. Biological elemental analysis: A cute‐meet of microfluidic device to inductively coupled plasma mass spectrometry. VIEW 2022. [DOI: 10.1002/viw.20220035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Xuan Zhang
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
| | - Junjie Bai
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
| | - Rui Wang
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
| | - Xing Wei
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
| | - Mingli Chen
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
| | - Ting Yang
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
| | - Jianhua Wang
- Research Center for Analytical Sciences, Department of Chemistry, College of Sciences Northeastern University Shenyang Liaoning China
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4
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Lores-Padín A, Fernández B, García M, González-Iglesias H, Pereiro R. Real matrix-matched standards for quantitative bioimaging of cytosolic proteins in individual cells using metal nanoclusters as immunoprobes-label: A case study using laser ablation ICP-MS detection. Anal Chim Acta 2022; 1221:340128. [DOI: 10.1016/j.aca.2022.340128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/19/2022] [Accepted: 06/24/2022] [Indexed: 11/30/2022]
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5
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Spedalieri C, Kneipp J. Surface enhanced Raman scattering for probing cellular biochemistry. NANOSCALE 2022; 14:5314-5328. [PMID: 35315478 PMCID: PMC8988265 DOI: 10.1039/d2nr00449f] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Surface enhanced Raman scattering (SERS) from biomolecules in living cells enables the sensitive, but also very selective, probing of their biochemical composition. This minireview discusses the developments of SERS probing in cells over the past years from the proof-of-principle to observe a biochemical status to the characterization of molecule-nanostructure and molecule-molecule interactions and cellular processes that involve a wide variety of biomolecules and cellular compartments. Progress in applying SERS as a bioanalytical tool in living cells, to gain a better understanding of cellular physiology and to harness the selectivity of SERS, has been achieved by a combination of live cell SERS with several different approaches. They range from organelle targeting, spectroscopy of relevant molecular models, and the optimization of plasmonic nanostructures to the application of machine learning and help us to unify the information from defined biomolecules and from the cell as an extremely complex system.
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Affiliation(s)
- Cecilia Spedalieri
- Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - Janina Kneipp
- Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
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6
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Drescher D, Büchner T, Schrade P, Traub H, Werner S, Guttmann P, Bachmann S, Kneipp J. Influence of Nuclear Localization Sequences on the Intracellular Fate of Gold Nanoparticles. ACS NANO 2021; 15:14838-14849. [PMID: 34460234 DOI: 10.1021/acsnano.1c04925] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Directing nanoparticles to the nucleus by attachment of nuclear localization sequences (NLS) is an aim in many applications. Gold nanoparticles modified with two different NLS were studied while crossing barriers of intact cells, including uptake, endosomal escape, and nuclear translocation. By imaging of the nanoparticles and by characterization of their molecular interactions with surface-enhanced Raman scattering (SERS), it is shown that nuclear translocation strongly depends on the particular incubation conditions. After an 1 h of incubation followed by a 24 h chase time, 14 nm gold particles carrying an adenoviral NLS are localized in endosomes, in the cytoplasm, and in the nucleus of fibroblast cells. In contrast, the cells display no nanoparticles in the cytoplasm or nucleus when continuously incubated with the nanoparticles for 24 h. The ultrastructural and spectroscopic data indicate different processing of NLS-functionalized particles in endosomes compared to unmodified particles. NLS-functionalized nanoparticles form larger intraendosomal aggregates than unmodified gold nanoparticles. SERS spectra of cells with NLS-functionalized gold nanoparticles contain bands assigned to DNA and were clearly different from those with unmodified gold nanoparticles. The different processing in the presence of an NLS is influenced by a continuous exposure of the cells to nanoparticles and an ongoing nanoparticle uptake. This is supported by mass-spectrometry-based quantification that indicates enhanced uptake of NLS-functionalized nanoparticles compared to unmodified particles under the same conditions. The results contribute to the optimization of nanoparticle analysis in cells in a variety of applications, e.g., in theranostics, biotechnology, and bioanalytics.
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Affiliation(s)
- Daniela Drescher
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Tina Büchner
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Petra Schrade
- Core Facility für Elektronenmikroskopie, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Heike Traub
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Straße 11, 12489 Berlin, Germany
| | - Stephan Werner
- Department of X-ray Microscopy, Helmholtz-Zentrum Berlin für Materialien und Energie, BESSY II, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - Peter Guttmann
- Department of X-ray Microscopy, Helmholtz-Zentrum Berlin für Materialien und Energie, BESSY II, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - Sebastian Bachmann
- Core Facility für Elektronenmikroskopie, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
- Department of Anatomy, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Janina Kneipp
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
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7
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Spedalieri C, Szekeres GP, Werner S, Guttmann P, Kneipp J. Intracellular optical probing with gold nanostars. NANOSCALE 2021; 13:968-979. [PMID: 33367430 DOI: 10.1039/d0nr07031a] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Gold nanostars are important nanoscopic tools in biophotonics and theranostics. To understand the fate of such nanostructures in the endolysosomal system of living cells as an important processing route in biotechnological approaches, un-labelled, non-targeted gold nanostars synthesized using HEPES buffer were studied in two cell lines. The uptake of the gold nanostructures leads to cell line-dependent intra-endolysosomal agglomeration, which results in a greater enhancement of the local optical fields than those around individual nanostars and near aggregates of spherical gold nanoparticles of the same size. As demonstrated by non-resonant surface-enhanced Raman scattering (SERS) spectra in the presence and absence of aggregation, the spectroscopic signals of molecules are of very similar strength over a wide range of concentrations, which is ideal for label-free vibrational characterization of cells and other complex environments. In 3T3 and HCT-116 cells, SERS data were analyzed together with the properties of the intracellular nanostar agglomerates. Vibrational spectra indicate that the processing of nanostars by cells and their interaction with the surrounding endolysosomal compartment is connected to their morphological properties through differences in the structure and interactions in their intracellular protein corona. Specifically, different intracellular processing was found to result from a different extent of hydrophobic interactions at the pristine gold surface, which varies for nanostars of different spike lengths. The sensitive optical monitoring of surroundings of nanostars and their intracellular processing makes them a very useful tool for optical bionanosensing and therapy.
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Affiliation(s)
- Cecilia Spedalieri
- Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
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8
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Stewart TJ. Across the spectrum: integrating multidimensional metal analytics for in situ metallomic imaging. Metallomics 2020; 11:29-49. [PMID: 30499574 PMCID: PMC6350628 DOI: 10.1039/c8mt00235e] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
To know how much of a metal species is in a particular location within a biological context at any given time is essential for understanding the intricate roles of metals in biology and is the fundamental question upon which the field of metallomics was born. Simply put, seeing is powerful. With the combination of spectroscopy and microscopy, we can now see metals within complex biological matrices complemented by information about associated molecules and their structures. With the addition of mass spectrometry and particle beam based techniques, the field of view grows to cover greater sensitivities and spatial resolutions, addressing structural, functional and quantitative metallomic questions from the atomic level to whole body processes. In this perspective, I present a paradigm shift in the way we relate to and integrate current and developing metallomic analytics, highlighting both familiar and perhaps less well-known state of the art techniques for in situ metallomic imaging, specific biological applications, and their use in correlative studies. There is a genuine need to abandon scientific silos and, through the establishment of a metallomic scientific platform for further development of multidimensional analytics for in situ metallomic imaging, we have an incredible opportunity to enhance the field of metallomics and demonstrate how discovery research can be done more effectively.
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Affiliation(s)
- Theodora J Stewart
- King's College London, Mass Spectrometry, London Metallomics Facility, 4th Floor Franklin-Wilkins Building, 150 Stamford St., London SE1 9NH, UK.
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9
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Flesch J, Kappen M, Drees C, You C, Piehler J. Self-assembly of robust gold nanoparticle monolayer architectures for quantitative protein interaction analysis by LSPR spectroscopy. Anal Bioanal Chem 2020; 412:3413-3422. [PMID: 32198532 PMCID: PMC7214499 DOI: 10.1007/s00216-020-02551-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/13/2020] [Accepted: 02/26/2020] [Indexed: 11/30/2022]
Abstract
Localized surface plasmon resonance (LSPR) detection offers highly sensitive label-free detection of biomolecular interactions. Simple and robust surface architectures compatible with real-time detection in a flow-through system are required for broad application in quantitative interaction analysis. Here, we established self-assembly of a functionalized gold nanoparticle (AuNP) monolayer on a glass substrate for stable, yet reversible immobilization of Histidine-tagged proteins. To this end, one-step coating of glass substrates with poly-L-lysine graft poly(ethylene glycol) functionalized with ortho-pyridyl disulfide (PLL-PEG-OPSS) was employed as a reactive, yet biocompatible monolayer to self-assemble AuNP into a LSPR active monolayer. Site-specific, reversible immobilization of His-tagged proteins was accomplished by coating the AuNP monolayer with tris-nitrilotriacetic acid (trisNTA) PEG disulfide. LSPR spectroscopy detection of protein binding on these biocompatible functionalized AuNP monolayers confirms high stability under various harsh analytical conditions. These features were successfully employed to demonstrate unbiased kinetic analysis of cytokine-receptor interactions. Graphical abstract ![]()
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Affiliation(s)
- Julia Flesch
- Department of Biology/Chemistry, University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany
| | - Marie Kappen
- Department of Biology/Chemistry, University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany
| | - Christoph Drees
- Department of Biology/Chemistry, University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany
| | - Changjiang You
- Department of Biology/Chemistry, University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany.
- Center for Cellular Nanoanalytics (CellNanOs), University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany.
| | - Jacob Piehler
- Department of Biology/Chemistry, University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany.
- Center for Cellular Nanoanalytics (CellNanOs), University of Osnabrück, Barbarastr. 11, 49076, Osnabrück, Germany.
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10
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Vaneckova T, Bezdekova J, Tvrdonova M, Vlcnovska M, Novotna V, Neuman J, Stossova A, Kanicky V, Adam V, Vaculovicova M, Vaculovic T. CdS quantum dots-based immunoassay combined with particle imprinted polymer technology and laser ablation ICP-MS as a versatile tool for protein detection. Sci Rep 2019; 9:11840. [PMID: 31413275 PMCID: PMC6694198 DOI: 10.1038/s41598-019-48290-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 08/01/2019] [Indexed: 01/07/2023] Open
Abstract
For the first time, the combination of molecularly imprinted polymer (MIP) technology with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is presented with focus on an optimization of the LA-ICP-MS parameters such as laser beam diameter, laser beam fluence, and scan speed using CdS quantum dots (QDs) as a template and dopamine as a functional monomer. A non-covalent imprinting approach was employed in this study due to the simplicity of preparation. Simple oxidative polymerization of the dopamine that creates the self-assembly monolayer seems to be an ideal choice. The QDs prepared by UV light irradiation synthesis were stabilized by using mercaptosuccinic acid. Formation of a complex of QD-antibody and QD-antibody-antigen was verified by using capillary electrophoresis with laser-induced fluorescence detection. QDs and antibody were connected together via an affinity peptide linker. LA-ICP-MS was employed as a proof-of-concept for detection method of two types of immunoassay: 1) antigen extracted from the sample by MIP and subsequently overlaid/immunoreacted by QD-labelled antibodies, 2) complex of antigen, antibody, and QD formed in the sample and subsequently extracted by MIP. The first approach provided higher sensitivity (MIP/NIP), however, the second demonstrated higher selectivity. A mixture of proteins with size in range 10–250 kDa was used as a model sample to demonstrate the capability of both approaches for detection of IgG in a complex sample.
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Affiliation(s)
- Tereza Vaneckova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00, Brno, Czech Republic
| | - Jaroslava Bezdekova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00, Brno, Czech Republic
| | - Michaela Tvrdonova
- Department of Chemistry, Masaryk University, Kamenice 753/5, CZ-625 00, Brno, Czech Republic
| | - Marcela Vlcnovska
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00, Brno, Czech Republic
| | - Veronika Novotna
- NenoVision s.r.o., Purkynova 649/127, CZ-612 00, Brno, Czech Republic
| | - Jan Neuman
- NenoVision s.r.o., Purkynova 649/127, CZ-612 00, Brno, Czech Republic
| | - Aneta Stossova
- Department of Chemistry, Masaryk University, Kamenice 753/5, CZ-625 00, Brno, Czech Republic
| | - Viktor Kanicky
- Department of Chemistry, Masaryk University, Kamenice 753/5, CZ-625 00, Brno, Czech Republic
| | - Vojtech Adam
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00, Brno, Czech Republic
| | - Marketa Vaculovicova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00, Brno, Czech Republic. .,Central European Institute of Technology, Brno University of Technology, Purkynova 123, CZ-612 00, Brno, Czech Republic.
| | - Tomas Vaculovic
- Department of Chemistry, Masaryk University, Kamenice 753/5, CZ-625 00, Brno, Czech Republic
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11
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Drescher D, Büchner T, Guttmann P, Werner S, Schneider G, Kneipp J. X-ray tomography shows the varying three-dimensional morphology of gold nanoaggregates in the cellular ultrastructure. NANOSCALE ADVANCES 2019; 1:2937-2945. [PMID: 36133586 PMCID: PMC9418343 DOI: 10.1039/c9na00198k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 06/08/2019] [Indexed: 05/28/2023]
Abstract
The processing of nanoparticles inside eukaryotic cells is a key step in many wanted and unwanted nano-bio-interactions. In order to understand the effects and functions of the intracellular aggregates that are formed, their properties and their interaction with the biological matrix must be characterized. High quality synchrotron soft X-ray tomography (SXT) data were obtained from cells containing gold nanoparticles that are commonly applied as tools for optical probing or drug delivery. 3D volume rendering of both cellular organelles and the nanoparticle aggregates of different sizes in the intact cells of two cell lines reveals variation in localization, size, shape and density of the intracellular gold nanoaggregates. The dependence of such variation on incubation time and cell type, as well as on the influence of pre-aggregation of primary nanoparticles is shown. The SXT results provide a detailed picture of intracellular aggregation and will improve the design of safe and efficient nanoparticle platforms for biomedical use.
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Affiliation(s)
- Daniela Drescher
- Humboldt-Universität zu Berlin, Department of Chemistry Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Tina Büchner
- Humboldt-Universität zu Berlin, Department of Chemistry Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Peter Guttmann
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Research Group X-ray Microscopy Albert-Einstein-Str. 15 12489 Berlin Germany
| | - Stephan Werner
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Research Group X-ray Microscopy Albert-Einstein-Str. 15 12489 Berlin Germany
| | - Gerd Schneider
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Research Group X-ray Microscopy Albert-Einstein-Str. 15 12489 Berlin Germany
| | - Janina Kneipp
- Humboldt-Universität zu Berlin, Department of Chemistry Brook-Taylor-Str. 2 12489 Berlin Germany
- School of Analytical Sciences Adlershof, Humboldt-Universität zu Berlin Albert-Einstein-Str. 5-9 12489 Berlin Germany
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12
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Öztaş DY, Altunbek M, Uzunoglu D, Yılmaz H, Çetin D, Suludere Z, Çulha M. Tracing Size and Surface Chemistry-Dependent Endosomal Uptake of Gold Nanoparticles Using Surface-Enhanced Raman Scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4020-4028. [PMID: 30773019 DOI: 10.1021/acs.langmuir.8b03988] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Surface-enhanced Raman scattering (SERS)-based single-cell analysis is an emerging approach to obtain molecular level information from molecular dynamics in a living cell. In this study, endosomal biochemical dynamics was investigated based on size and surface chemistry-dependent uptake of gold nanoparticles (AuNPs) on single cells over time using SERS. MDA-MB-231 breast cancer cells were exposed to 13 and 50 nm AuNPs and their polyadenine oligonucleotide-modified forms by controlling the order and combination of AuNPs. The average spectra obtained from 20 single cells were analyzed to study the nature of the biochemical species or processes taking place on the AuNP surfaces. The spectral changes, especially from proteins and lipids of endosomal vesicles, were observed depending on the size, surface chemistry, and combination as well as the duration of the AuNP treatment. The results demonstrate that SERS spectra are sensitive to trace biochemical changes not only the size, surface chemistry, and aggregation status of AuNPs but also the endosomal maturation steps over time, which can be simple and fast way for understanding the AuNP behavior in single cell and useful for the assisting and controlling of AuNP-based gene or drug delivery applications.
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Affiliation(s)
- Deniz Yaşar Öztaş
- Department of Genetics and Bioengineering, Faculty of Engineering , Yeditepe University , Ataşehir, Istanbul 34755 , Turkey
| | - Mine Altunbek
- Department of Genetics and Bioengineering, Faculty of Engineering , Yeditepe University , Ataşehir, Istanbul 34755 , Turkey
| | - Deniz Uzunoglu
- Department of Genetics and Bioengineering, Faculty of Engineering , Yeditepe University , Ataşehir, Istanbul 34755 , Turkey
| | - Hülya Yılmaz
- Department of Genetics and Bioengineering, Faculty of Engineering , Yeditepe University , Ataşehir, Istanbul 34755 , Turkey
| | | | | | - Mustafa Çulha
- Department of Genetics and Bioengineering, Faculty of Engineering , Yeditepe University , Ataşehir, Istanbul 34755 , Turkey
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13
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Tvrdonova M, Vlcnovska M, Vanickova LP, Kanicky V, Adam V, Ascher L, Jakubowski N, Vaculovicova M, Vaculovic T. Gold nanoparticles as labels for immunochemical analysis using laser ablation inductively coupled plasma mass spectrometry. Anal Bioanal Chem 2018; 411:559-564. [PMID: 30109381 DOI: 10.1007/s00216-018-1300-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 07/20/2018] [Accepted: 07/27/2018] [Indexed: 12/17/2022]
Abstract
In this paper, we describe the labelling of antibodies by gold nanoparticles (AuNPs) with diameters of 10 and 60 nm with detection by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Additionally, the AuNPs labelling strategy is compared with commercially available labelling reagents based on MeCAT (metal coded affinity tagging). Proof of principle experiments based on dot blot experiments were performed. The two labelling methods investigated were compared by sensitivity and limit of detection (LOD). The absolute LODs achieved were in the range of tens of picograms for AuNP labelling compared to a few hundred picograms by the MeCAT labelling.
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Affiliation(s)
- Michaela Tvrdonova
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.,CEITEC, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Marcela Vlcnovska
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, 613 00, Brno, Czech Republic
| | - Lucie Pompeiano Vanickova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, 613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00, Brno, Czech Republic
| | - Viktor Kanicky
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.,CEITEC, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Vojtech Adam
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, 613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00, Brno, Czech Republic
| | - Lena Ascher
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Straße 11, 12489, Berlin, Germany
| | - Norbert Jakubowski
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Straße 11, 12489, Berlin, Germany
| | - Marketa Vaculovicova
- Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, 613 00, Brno, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00, Brno, Czech Republic
| | - Tomas Vaculovic
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic. .,Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00, Brno, Czech Republic.
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14
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Zheng XS, Jahn IJ, Weber K, Cialla-May D, Popp J. Label-free SERS in biological and biomedical applications: Recent progress, current challenges and opportunities. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 197:56-77. [PMID: 29395932 DOI: 10.1016/j.saa.2018.01.063] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 01/19/2018] [Accepted: 01/23/2018] [Indexed: 05/04/2023]
Abstract
To achieve an insightful look within biomolecular processes on the cellular level, the development of diseases as well as the reliable detection of metabolites and pathogens, a modern analytical tool is needed that is highly sensitive, molecular-specific and exhibits fast detection. Surface-enhanced Raman spectroscopy (SERS) is known to meet these requirements and, within this review article, the recent progress of label-free SERS in biological and biomedical applications is summarized and discussed. This includes the detection of biomolecules such as metabolites, nucleic acids and proteins. Further, the characterization and identification of microorganisms has been achieved by label-free SERS-based approaches. Eukaryotic cells can be characterized by SERS in order to gain information about the outer cell wall or to detect intracellular molecules and metabolites. The potential of SERS for medically relevant detection schemes is emphasized by the label-free detection of tissue, the investigation of body fluids as well as applications for therapeutic and illicit drug monitoring. The review article is concluded with an evaluation of the recent progress and current challenges in order to highlight the direction of label-free SERS in the future.
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Affiliation(s)
- Xiao-Shan Zheng
- Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Str. 9, 07745 Jena, Germany
| | - Izabella Jolan Jahn
- Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Str. 9, 07745 Jena, Germany
| | - Karina Weber
- Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Str. 9, 07745 Jena, Germany; Friedrich Schiller University Jena, Institute of Physical Chemistry and Abbe Center of Photonics, Helmholtzweg 4, 07745 Jena, Germany; Research Campus Infectognostic, Philosophenweg 7, 07743 Jena, Germany
| | - Dana Cialla-May
- Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Str. 9, 07745 Jena, Germany; Friedrich Schiller University Jena, Institute of Physical Chemistry and Abbe Center of Photonics, Helmholtzweg 4, 07745 Jena, Germany; Research Campus Infectognostic, Philosophenweg 7, 07743 Jena, Germany.
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology Jena, Albert-Einstein-Str. 9, 07745 Jena, Germany; Friedrich Schiller University Jena, Institute of Physical Chemistry and Abbe Center of Photonics, Helmholtzweg 4, 07745 Jena, Germany; Research Campus Infectognostic, Philosophenweg 7, 07743 Jena, Germany.
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15
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Cryo-soft X-ray tomography: using soft X-rays to explore the ultrastructure of whole cells. Emerg Top Life Sci 2018; 2:81-92. [PMID: 33525785 PMCID: PMC7289011 DOI: 10.1042/etls20170086] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Revised: 01/31/2018] [Accepted: 02/02/2018] [Indexed: 12/31/2022]
Abstract
Cryo-soft X-ray tomography is an imaging technique that addresses the need for mesoscale imaging of cellular ultrastructure of relatively thick samples without the need for staining or chemical modification. It allows the imaging of cellular ultrastructure to a resolution of 25–40 nm and can be used in correlation with other imaging modalities, such as electron tomography and fluorescence microscopy, to further enhance the information content derived from biological samples. An overview of the technique, discussion of sample suitability and information about sample preparation, data collection and data analysis is presented here. Recent developments and future outlook are also discussed.
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16
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Laux P, Tentschert J, Riebeling C, Braeuning A, Creutzenberg O, Epp A, Fessard V, Haas KH, Haase A, Hund-Rinke K, Jakubowski N, Kearns P, Lampen A, Rauscher H, Schoonjans R, Störmer A, Thielmann A, Mühle U, Luch A. Nanomaterials: certain aspects of application, risk assessment and risk communication. Arch Toxicol 2018; 92:121-141. [PMID: 29273819 PMCID: PMC5773666 DOI: 10.1007/s00204-017-2144-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/13/2017] [Indexed: 12/19/2022]
Abstract
Development and market introduction of new nanomaterials trigger the need for an adequate risk assessment of such products alongside suitable risk communication measures. Current application of classical and new nanomaterials is analyzed in context of regulatory requirements and standardization for chemicals, food and consumer products. The challenges of nanomaterial characterization as the main bottleneck of risk assessment and regulation are presented. In some areas, e.g., quantification of nanomaterials within complex matrices, the establishment and adaptation of analytical techniques such as laser ablation inductively coupled plasma mass spectrometry and others are potentially suited to meet the requirements. As an example, we here provide an approach for the reliable characterization of human exposure to nanomaterials resulting from food packaging. Furthermore, results of nanomaterial toxicity and ecotoxicity testing are discussed, with concluding key criteria such as solubility and fiber rigidity as important parameters to be considered in material development and regulation. Although an analysis of the public opinion has revealed a distinguished rating depending on the particular field of application, a rather positive perception of nanotechnology could be ascertained for the German public in general. An improvement of material characterization in both toxicological testing as well as end-product control was concluded as being the main obstacle to ensure not only safe use of materials, but also wide acceptance of this and any novel technology in the general public.
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Affiliation(s)
- Peter Laux
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany.
| | - Jutta Tentschert
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Christian Riebeling
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Albert Braeuning
- Department of Food Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Otto Creutzenberg
- Department of Inhalation Toxicology, Fraunhofer-Institute for Toxicology and Experimental Medicine (ITEM), Nikolai Fuchs Strasse 1, 30625, Hannover, Germany
| | - Astrid Epp
- Department of Risk Communication, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Valérie Fessard
- Laboratoire de Fougères, French Agency for Food, Environmental and Occupational Health and Safety (ANSES), 10B Rue Claude Bourgelat, 35306, Fougères Cedex, France
| | - Karl-Heinz Haas
- Fraunhofer Institute for Silicate Research ISC, Neunerplatz 2, 97082, Würzburg, Germany
| | - Andrea Haase
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Kerstin Hund-Rinke
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Auf Dem Aberg 1, 57392, Schmallenberg, Germany
| | - Norbert Jakubowski
- Division 1.1 Inorganic Trace Analysis, Federal Institute for Materials Research and Testing (BAM), Richard-Willstaetter-Str. 11, 12489, Berlin, Germany
| | - Peter Kearns
- OECD Environment, Health and Safety Division 2, rue Andre-Pascal, 75775, Paris Cedex 16, France
| | - Alfonso Lampen
- Department of Food Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Hubert Rauscher
- Joint Research Centre (JRC) of the European Commission, Directorate Health, Consumers and Reference Materials, Via E. Fermi, 2749, 21027, Ispra, Italy
| | - Reinhilde Schoonjans
- Scientific Committee and Emerging Risks Unit, European Food Safety Authority (EFSA), Via Carlo Magno 1a, 43126, Parma, Italy
| | - Angela Störmer
- Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Strasse 35, 85354, Freising, Germany
| | - Axel Thielmann
- Fraunhofer Institute for Systems and Innovation Research ISI, Breslauer Strasse 48, 76139, Karlsruhe, Germany
| | - Uwe Mühle
- Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Winterbergstr. 28, 01277, Dresden, Germany
| | - Andreas Luch
- Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
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17
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Kuku G, Altunbek M, Culha M. Surface-Enhanced Raman Scattering for Label-Free Living Single Cell Analysis. Anal Chem 2017; 89:11160-11166. [DOI: 10.1021/acs.analchem.7b03211] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Gamze Kuku
- Department of Genetics and
Bioengineering, Yeditepe University, 34755, Istanbul, Turkey
| | - Mine Altunbek
- Department of Genetics and
Bioengineering, Yeditepe University, 34755, Istanbul, Turkey
| | - Mustafa Culha
- Department of Genetics and
Bioengineering, Yeditepe University, 34755, Istanbul, Turkey
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18
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Kopp M, Kollenda S, Epple M. Nanoparticle-Protein Interactions: Therapeutic Approaches and Supramolecular Chemistry. Acc Chem Res 2017; 50:1383-1390. [PMID: 28480714 DOI: 10.1021/acs.accounts.7b00051] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Research on nanoparticles has evolved into a major topic in chemistry. Concerning biomedical research, nanoparticles have decisively entered the field, creating the area of nanomedicine where nanoparticles are used for drug delivery, imaging, and tumor targeting. Besides these functions, scientists have addressed the specific ways in which nanoparticles interact with biomolecules, with proteins being the most prominent example. Depending on their size, shape, charge, and surface functionality, specifically designed nanoparticles can interact with proteins in a defined way. Proteins have typical dimensions of 5-20 nm. Ultrasmall nanoparticles (size about 1-2 nm) can address specific epitopes on the surface of a protein, for example, an active center of an enzyme. Medium-sized nanoparticles (size about 5 nm) can interact with proteins on a 1:1 basis. Large nanoparticles (above 20 nm) are big in comparison to many proteins and therefore are at the borderline to a two-dimensional surface onto which a protein will adsorb. This can still lead to irreversible structural changes in a protein and a subsequent loss of function. However, as most cells readily take up nanoparticles of almost any size, it is easily possible to use nanoparticles as transporters for proteins into a cell, for example, to address an internal receptor. Much work has been dedicated to this approach, but it is constrained by two processes that can only be observed in living cells or organisms. First, nanoparticles are usually taken up by endocytosis and are delivered into an intracellular endosome. After fusion with a lysosome, a degradation or denaturation of the protein cargo by the acidic environment or by proteases may occur before it can enter the cytoplasm. Second, nanoparticles are rapidly coated with proteins upon contact with biological media like blood. This so-called protein corona influences the contact with other proteins, cells, or tissue and may prevent the desired interaction. Essentially, these effects cannot be understood in purely chemical approaches but require biological environments and systems because the underlying processes are simply too complicated to be modeled in nonbiological systems. The area of nanoparticle-protein interactions strongly relies on different approaches: Synthetic chemistry is involved to prepare, stabilize, and functionalize nanoparticles. High-end analytical chemistry is required to understand the nature of a nanoparticle surface and the steps of its interaction with proteins. Concepts from supramolecular chemistry help to understand the complex noncovalent interactions between the surfaces of proteins and nanoparticles. Protein chemistry and biophysical chemistry are required to understand the behavior of a protein in contact with a nanoparticle. Finally, all chemical concepts must live up to the "biological reality", first in cell culture experiments in vitro and finally in animal or human experiments in vivo, to open new therapies in the 21st century. This interdisciplinary approach makes the field highly exciting but also highly demanding for chemists who, however, have to learn to understand the language of other areas.
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Affiliation(s)
- Mathis Kopp
- Inorganic Chemistry and Center for Nanointegration
Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitaetsstr. 5-7, 45117 Essen, Germany
| | - Sebastian Kollenda
- Inorganic Chemistry and Center for Nanointegration
Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitaetsstr. 5-7, 45117 Essen, Germany
| | - Matthias Epple
- Inorganic Chemistry and Center for Nanointegration
Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitaetsstr. 5-7, 45117 Essen, Germany
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19
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Sobral-Filho RG, Brito-Silva AM, Isabelle M, Jirasek A, Lum JJ, Brolo AG. Plasmonic labeling of subcellular compartments in cancer cells: multiplexing with fine-tuned gold and silver nanoshells. Chem Sci 2017; 8:3038-3046. [PMID: 28451372 PMCID: PMC5380877 DOI: 10.1039/c6sc04127b] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 01/29/2017] [Indexed: 01/01/2023] Open
Abstract
Fine-tuned gold and silver nanoshells were produced via an entirely reformulated synthesis. The new method yielded ultramonodisperse samples, with polydispersity indexes (PI) as low as 0.02 and narrow extinction bands suited for multiplex analysis. A library of nanoshell samples with localized surface plasmon resonances (LSPR) spanning across the visible range was synthesized. Hyperspectral analysis revealed that the average scattering spectrum of 100 nanoshells matched closely to the spectrum of a single nanoshell, indicating an unprecedented low level of nanoparticle-to-nanoparticle variation for this type of system. A cell labeling experiment, targeting different subcellular compartments in MCF-7 human breast cancer cells, demonstrated that these monodisperse nanoparticles can be used as a multiplex platform for single cell analysis at the intracellular and extracellular level. Antibody-coated gold nanoshells targeted the plasma membrane, while silver nanoshells coated with a nuclear localization signal (NLS) targeted the nuclear membrane. A fluorescence counterstaining experiment, as well as single cell hyperspectral microscopy showed the excellent selectivity and specificity of each type of nanoparticle for its designed subcellular compartment. A time-lapse photodegradation experiment confirmed the enhanced stability of the nanoshells over fluorescent labeling and their capabilities for long-term live cell imaging.
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Affiliation(s)
- R G Sobral-Filho
- Department of Chemistry , University of Victoria , 3800 Finnerty Road , Victoria BC V8P 5C2 , Canada .
| | - A M Brito-Silva
- Department of Chemistry , University of Victoria , 3800 Finnerty Road , Victoria BC V8P 5C2 , Canada .
| | - M Isabelle
- British Columbia Cancer Agency - Vancouver Island Centre , Trev and Joyce Deeley Research Centre , 2410 Lee Ave. , Victoria , BC V8R 6V5 , Canada
| | - A Jirasek
- Department of Mathematics , Statistics, Physics and Computer Science , University of British Columbia Okanagan , 3187 University Way , Kelowna BC V1V 1V7 , Canada
| | - J J Lum
- British Columbia Cancer Agency - Vancouver Island Centre , Trev and Joyce Deeley Research Centre , 2410 Lee Ave. , Victoria , BC V8R 6V5 , Canada
- Department of Biochemistry and Microbiology , University of Victoria , 3800 Finnerty Road , Victoria BC V8P 5C2 , Canada
| | - A G Brolo
- Department of Chemistry , University of Victoria , 3800 Finnerty Road , Victoria BC V8P 5C2 , Canada .
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