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Altman LE, Grier DG. Interpreting holographic molecular binding assays with effective medium theory. BIOMEDICAL OPTICS EXPRESS 2020; 11:5225-5236. [PMID: 33014610 PMCID: PMC7510853 DOI: 10.1364/boe.401103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/08/2020] [Accepted: 08/14/2020] [Indexed: 05/28/2023]
Abstract
Holographic molecular binding assays use holographic video microscopy to directly detect molecules binding to the surfaces of micrometer-scale colloidal beads by monitoring associated changes in the beads' light-scattering properties. Holograms of individual spheres are analyzed by fitting to a generative model based on the Lorenz-Mie theory of light scattering. Each fit yields an estimate of a probe bead's diameter and refractive index with sufficient precision to watch a population of beads grow as molecules bind. Rather than modeling the molecular-scale coating, however, these fits use effective medium theory, treating the coated sphere as if it were homogeneous. This effective-sphere analysis is rapid and numerically robust and so is useful for practical implementations of label-free immunoassays. Here, we assess how measured effective-sphere properties reflect the actual properties of molecular-scale coatings by modeling coated spheres with the discrete-dipole approximation and analyzing their holograms with the effective-sphere model.
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Fluorescent Submicron-Sized Poly(heptafluoro- n-butyl methacrylate) Particles with Long-Term Stability. Molecules 2020; 25:molecules25092013. [PMID: 32344920 PMCID: PMC7249074 DOI: 10.3390/molecules25092013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 04/19/2020] [Accepted: 04/23/2020] [Indexed: 11/17/2022] Open
Abstract
Fluorescent submicron particles of fluorinated methacrylate (HFMBA) with long-term stability have been synthesized and characterized with regard to their potential applications. Rhodamine B (RBITC) isothiocyanate was used as the fluorescent component. The core–shell structure of the particles effectively protected the dye against bleaching. HFBMA nanoparticle (NP) stability was confirmed after seven years of storage. Only slight differences were found in the polydispersity index (pdi) from 0.002 to 0.010. Particle size measurements were carried out using dynamic light scattering (DLS), nanoparticle tracking (NTA), and fluorescence correlation spectroscopy (FCS). The hydrodynamic diameter evaluated by different methods were in good agreement, respectively: 184–550 nm, 218–579 nm, and 236–508 nm. Particle and core morphology was estimated by using scanning and transmission electron microscopy (SEM and TEM). The ability to recognize particles in 3D as a reference sample in biological media has been confirmed by epifluorescence optical microscopy, confocal laser scanning microscopy, and super-resolution confocal microscopy (STED).
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Jarzębski M, Peplińska B, Florczak P, Gapiński J, Flak D, Mała P, Ramanavicius A, Baryła-Pankiewicz E, Kobus- Cisowska J, Szwajca A. Fluorescein ether-ester dyes for labeling of fluorinated methacrylate nanoparticles. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.111956] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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4
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Payamyar P. Transparent microparticles in water/sucrose solution. SOFT MATTER 2019; 15:4428-4431. [PMID: 31099815 DOI: 10.1039/c9sm00698b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Facile, one-step dispersion polymerization of heptafluoro-n-butyl methacrylate is shown to provide microparticles that can be made transparent in the bio-friendly medium of water/sucrose with a refractive index of 1.3770. Fluorescently labeled particles can be imaged 80 μm deep into the dispersion with 1 vol% concentration, using confocal fluorescence microscopy. Such particles can provide insights into (bio-)physical processes in aqueous environments.
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Affiliation(s)
- Payam Payamyar
- Harvard John A. Paulson School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA.
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Semi-batch synthesis of colloidal spheres with fluorinated cores and varying grafts of poly(ethylene glycol). Colloid Polym Sci 2017; 295:1983-1991. [PMID: 28989224 PMCID: PMC5602058 DOI: 10.1007/s00396-017-4172-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 07/27/2017] [Accepted: 07/27/2017] [Indexed: 11/02/2022]
Abstract
Fluorinated spheres with grafted poly(ethylene glycol) (PEG) have been synthesized using a semi-batch emulsion polymerization in which the initiator is fed slowly to the reaction. In this way, PEG-grafted colloidal spheres can be fabricated with varying PEG chain length, different cores and varying degrees of crosslinking. The resulting batches have been characterized using disc centrifuge photosedimentometry and small-angle X-ray scattering. The size distribution is shown to be a sensitive function of the molar ratio of the reactive PEG macromonomer to fluorinated monomer, and with some optimization latices of very low polydispersity can be obtained with this simple synthesis method. For short PEG grafts too high a molar ratio results in a build up of smaller size particles and a broadening of the size distribution, whereas for longer grafts the mean particle size increases with decreasing molar ratio.
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Zupkauskas M, Lan Y, Joshi D, Ruff Z, Eiser E. Optically transparent dense colloidal gels. Chem Sci 2017; 8:5559-5566. [PMID: 28970935 PMCID: PMC5618774 DOI: 10.1039/c7sc00901a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 05/25/2017] [Indexed: 11/21/2022] Open
Abstract
Traditionally it has been difficult to study the porous structure of dense colloidal gels and (macro) molecular transport through them simply because of the difference in refractive index between the colloid material and the continuous fluid phase surrounding it, rendering the samples opaque even at low colloidal volume fractions. Here, we demonstrate a novel colloidal gel that can be refractive index-matched in aqueous solutions owing to the low refractive index of fluorinated latex (FL)-particles (n = 1.37). Synthesizing them from heptafluorobutyl methacrylate using emulsion polymerization, we demonstrate that they can be functionalized with short DNA sequences via a dense brush-layer of polystyrene-b-poly(ethylene oxide) block-copolymers (PS-PEO). The block-copolymer, holding an azide group at the free PEO end, was grafted to the latex particle utilizing a swelling-deswelling method. Subsequently, DNA was covalently attached to the azide-end of the block copolymer via a strain-promoted alkyne-azide click reaction. For comparison, we present a structural study of single gels made of FL-particles only and composite gels made of a percolating FL-colloid gel coated with polystyrene (PS) colloids. Further we demonstrate that the diffusivity of tracer colloids dispersed deep inside a refractive index matched FL-colloidal gel can be measured as function of the local confinement using Dynamic Differential Microscopy (DDM).
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Affiliation(s)
- M Zupkauskas
- Optoelectronics Group , Department of Physics , Cavendish Laboratory , University of Cambridge , J J Thomson Avenue , Cambridge CB3 0HE , UK .
| | - Y Lan
- Optoelectronics Group , Department of Physics , Cavendish Laboratory , University of Cambridge , J J Thomson Avenue , Cambridge CB3 0HE , UK .
- Melville Laboratory for Polymer Synthesis , Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge , CB2 1EW , UK
- Collaborative Innovation Center of Chemical Science and Engineering , Institute of Polymer Chemistry , Nankai University , Tianjin 300071 , China
| | - D Joshi
- Optoelectronics Group , Department of Physics , Cavendish Laboratory , University of Cambridge , J J Thomson Avenue , Cambridge CB3 0HE , UK .
| | - Z Ruff
- Optoelectronics Group , Department of Physics , Cavendish Laboratory , University of Cambridge , J J Thomson Avenue , Cambridge CB3 0HE , UK .
| | - E Eiser
- Optoelectronics Group , Department of Physics , Cavendish Laboratory , University of Cambridge , J J Thomson Avenue , Cambridge CB3 0HE , UK .
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Jarzebski M, Zhang Y, Sliwa T, Mazuryk J, Deptula T, Kucinska M, Murias M, Buitenhuis J, Gapiński J, Patkowski A. Core–shell fluorinated methacrylate nanoparticles with Rhodamine-B for confocal microscopy and fluorescence correlation spectroscopy applications. J Fluor Chem 2016. [DOI: 10.1016/j.jfluchem.2016.01.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Ding X, Zhang B, Yang J, Ma ZJ, Fan G. Use of feedback system control in optimizing chemical combinations to synthesize nanoparticles with desired characteristics. RSC Adv 2016. [DOI: 10.1039/c5ra24218e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Defining desired chemical combinations through the FSC method.
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Affiliation(s)
- Xianting Ding
- Med-X Research Institute
- School of Biomedical Engineering
- Shanghai Jiao Tong University
- China
| | - Bing Zhang
- Institute of Process Equipment
- College of Chemical and Biological Engineering
- Zhejiang University
- China
| | - Jian Yang
- Institute of Process Equipment
- College of Chemical and Biological Engineering
- Zhejiang University
- China
| | - Zhi Jun Ma
- Department of Material Engineering
- South China University of Technology
- China
| | - Gang Fan
- Institute of Process Equipment
- College of Chemical and Biological Engineering
- Zhejiang University
- China
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Yang C, Castelvetro V, Scalarone D, Bianchi S, Zhang Y. Three different β-cyclodextrins direct the emulsion copolymerization of a highly fluorinated methacrylate toward distinctive nanostructured particle morphologies. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/pola.24921] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Misra A, Urban MW. Environmentally Compliant Fluoro-Containing MMA/nBA Colloidal Dispersions; Synthesis, Molecular Modeling, and Coalescence. Macromolecules 2009. [DOI: 10.1021/ma9012303] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anuradha Misra
- School of Polymers and High Performance Materials Shelby F. Thames
Polymer Science Research Center The University of Southern Mississippi
Hattiesburg, Mississippi 39406
| | - Marek W. Urban
- School of Polymers and High Performance Materials Shelby F. Thames
Polymer Science Research Center The University of Southern Mississippi
Hattiesburg, Mississippi 39406
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11
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Abstract
Core-shell materials, in which a layer or multilayer of inorganic or organic material surrounds an inorganic or organic particle core, have been investigated both as a means to improve the stability and surface chemistry of the core particle and as a way of accessing unique physical and chemical properties that are not possible from one material alone. As a result, the fabrication of core-shell particles is attracting a great deal of interest because of their unique properties and potential applicability in catalysis, semiconductors, drug delivery, enzyme immobilization, molecular recognition, chemical sensing, etc. As evidenced by the literature described and discussed in this review, a basic understanding of the mechanism and recent progress in production methods have enabled the fabrication of core-shell particles with unique and tailored properties for various applications in materials science.
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Misra A, Jarrett WL, Urban MW. Fluoromethacrylate-Containing Colloidal Dispersions: Phospholipid-Assisted Synthesis, Particle Morphology, and Temperature-Responsive Stratification. Macromolecules 2007. [DOI: 10.1021/ma070852k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anuradha Misra
- School of Polymers and High Performance Materials, Shelby F. Thames Polymer Science Research Center, The University of Southern Mississippi, Hattiesburg, Mississippi 39406-0076
| | - William L. Jarrett
- School of Polymers and High Performance Materials, Shelby F. Thames Polymer Science Research Center, The University of Southern Mississippi, Hattiesburg, Mississippi 39406-0076
| | - Marek W. Urban
- School of Polymers and High Performance Materials, Shelby F. Thames Polymer Science Research Center, The University of Southern Mississippi, Hattiesburg, Mississippi 39406-0076
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Matsumoto K, Kage S, Matsuoka H. Synthesis of water-dispersible, fluorinated particles with grafting sulfonate chains by the core crosslinking of block copolymer micelles. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/pola.21903] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Shimizu H, Shiraishi T, Wada R, Okabe M. Fluorinated monomer–styrene copolymer latex particles: I. kinetic studies in a soap-free aqueous medium. Colloid Polym Sci 2006. [DOI: 10.1007/s00396-006-1548-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Beach E, Keefe M, Heeschen W, Rothe D. Cross-sectional analysis of hollow latex particles by focused ion beam–scanning electron microscopy. POLYMER 2005. [DOI: 10.1016/j.polymer.2005.09.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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