Highly birefringent vaterite microspheres: production, characterization and applications for optical micromanipulation

Parkin, Simon J.; Vogel, Robert; Persson, Michael; Funk, Maren; Loke, Vincent L. Y.; Nieminen, Timo A.; Heckenberg, N. R.; Rubinsztein‐Dunlop, Halina

doi:10.1364/oe.17.021944

Cited by 71 publications

(59 citation statements)

References 46 publications

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“…So far, only pure insulin particles have been synthesized by infiltrating the internal structure of CaCO 3 microparticles but they collapsed after template removal 33, 34. CaCO 3 microparticles are constituted of crystallites (vaterite mainly) of about several tens of nanometers in size, arranged in a wheat sheaves‐like structure 35. The voids between these crystallites represent a channel‐like structure with interconnected pores.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Porous PEG Microgels Using CaCO₃ Microspheres as Hard Templates

Behra

Schmidt

Hartmann

et al. 2012

Macromol. Rapid Commun.

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Porous poly(ethylene glycol) (PEG) microgels of both 17.6 and 8.3 μm in diameter are synthesized via hard templating with calcium carbonate (CaCO(3)) microparticles. The synthesis is performed in three steps: loading of PEG macromonomers into CaCO(3) microparticles, crosslinking via photopolymerization, and removal of the CaCO(3) template under acidic conditions. The resulting porous PEG microgels are inverse replicates of their templates as indicated by light microscopy, cryo-scanning electron microscopy (cryo-SEM), and permeability studies. Thus this process allows for the straightforward and highly reproducible synthesis of porous hydrogel particles of two different diameters and porosities that show great potential as carriers for drugs or nanomaterials.

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Section: Introductionmentioning

confidence: 99%

Synthesis of Porous PEG Microgels Using CaCO₃ Microspheres as Hard Templates

Behra

Schmidt

Hartmann

et al. 2012

Macromol. Rapid Commun.

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“…[30] Today it is possible to produce optical functional CaCO 3 based materials like amorphous, nanocrystalline calcite and calcitic single crystal based microlens arrays as well as highly birefrin gent vaterite microspheres. [31] Often organic additives are used to guide the formation of complex shapes via selfassembly, [6,32] but also without using additives it is possible to get materials with complex shapes. [33] …”

Section: Artificial Calcium Carbonate Microlens Arraysmentioning

confidence: 99%

Tailoring Calcium Carbonate to Serve as Optical Functional Material: Examples from Biology and Materials Science

Schmidt

Wagermaier

2016

Adv Materials Inter

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In nature and technology there are many examples of micron sized optical systems based on minerals. The thermodynamically most stable polymorph of calcium carbonate (CaCO3) –calcite– exhibits birefringence. However, nature uses biomineralization approaches to produce CaCO3 based optical functional materials, for example calcite mircrolens arrays as part of the photoreceptor system of brittlestars, amorphous CaCO3 (ACC) plant cystoliths as light scatterers and calcite trilobite eyes. In this short review, we illustrate basic strategies to produce optical materials from CaCO3 by manipulating the material structure. These strategies are driven by the aim to eliminate or reduce the birefringent properties of calcite, or even, to turn this property into an advantage. We report on the formation, structure, and functions of micron sized (hemi-)spherical objects made from CaCO3 with biological origin but also in bio-inspired synthetic examples. We highlight aspects, which pave the way to learn from nature and how to characterize natural and artificial systems. In conclusion, we identify three main possibilities to make optical materials based on CaCO3: (i) orienting the optical axis along the desired light propagation direction, (ii) stabilizing metastable phases, and (iii) producing nanocrystalline structures, which reduce birefringent properties

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“…Most of the previous works on optimizing optical forces have focused on improving the trapping beam [14][15][16][17] while structure-related force optimization mostly involves material selection and antireflection coatings [18,19] or optically driven motors based on birefringence or light scattering [20][21][22][23]. In this work we bring focus to the object shaping aspects of optimizing the mechanical effects of optical fields.…”

Section: Introductionmentioning

confidence: 99%

Optical forces through guided light deflections

Palima¹,

Bañas²,

Vizsnyiczai³

et al. 2013

Opt. Express

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Optical trapping and manipulation typically relies on shaping focused light to control the optical force, usually on spherical objects. However, one can also shape the object to control the light deflection arising from the light-matter interaction and, hence, achieve desired optomechanical effects. In this work we look into the object shaping aspect and its potential for controlled optical manipulation. Using a simple bent waveguide as example, our numerical simulations show that the guided deflection of light efficiently converts incident light momentum into optical force with one order-of-magnitude improvement in the efficiency factor relative to a microbead, which is comparable to the improvement expected from orthogonal deflection with a perfect mirror. This improvement is illustrated in proof-of-principle experiments demonstrating the optical manipulation of two-photon polymerized waveguides. Results show that the force on the waveguide exceeds the combined forces on spherical trapping handles. Furthermore, it shows that static illumination can exert a constant force on a moving structure, unlike the position-dependent forces from harmonic potentials in conventional trapping.

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Highly birefringent vaterite microspheres: production, characterization and applications for optical micromanipulation

Cited by 71 publications

References 46 publications

Synthesis of Porous PEG Microgels Using CaCO₃ Microspheres as Hard Templates

Synthesis of Porous PEG Microgels Using CaCO₃ Microspheres as Hard Templates

Tailoring Calcium Carbonate to Serve as Optical Functional Material: Examples from Biology and Materials Science

Optical forces through guided light deflections

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Highly birefringent vaterite microspheres: production, characterization and applications for optical micromanipulation

Cited by 71 publications

References 46 publications

Synthesis of Porous PEG Microgels Using CaCO3 Microspheres as Hard Templates

Synthesis of Porous PEG Microgels Using CaCO3 Microspheres as Hard Templates

Tailoring Calcium Carbonate to Serve as Optical Functional Material: Examples from Biology and Materials Science

Optical forces through guided light deflections

Contact Info

Product

Resources

About

Synthesis of Porous PEG Microgels Using CaCO₃ Microspheres as Hard Templates

Synthesis of Porous PEG Microgels Using CaCO₃ Microspheres as Hard Templates