Facile fabrication of uniform golf-ball-shaped microparticles from various polymers

Hwangbo, Kyung-Hee; Kim, Mi Ri; Lee, Chang‐Soo; Cho, Kuk Young

doi:10.1039/c1sm06529g

Cited by 41 publications

(43 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These particles show some similarities to the "golf-ball" and "polyelectrolyte capsule" morphologies reported previously. 54,55 Figure 4a. For all PMMA-AA non-cross-linked particles, increasing the pH resulted in gradual dissociation of any large particles which were present into smaller aggregates, which eventually dissolved completely.…”

Section: ■ Experimental Sectionmentioning

confidence: 98%

Injectable Biocompatible and Biodegradable pH-Responsive Hollow Particle Gels Containing Poly(acrylic acid): The Effect of Copolymer Composition on Gel Properties

et al. 2014

View full text Add to dashboard Cite

The potential of various pH-responsive alkyl (meth)acrylate ester- and (meth)acrylic acid-based copolymers, including poly(methyl methacrylate-co-acrylic acid) (PMMA-AA) and poly(n-butyl acrylate-co-methacrylic acid) (PBA-MAA), to form pH-sensitive biocompatible and biodegradable hollow particle gel scaffolds for use in non-load-bearing soft tissue regeneration have been explored. The optimal copolymer design criteria for preparation of these materials have been established. Physical gels which are both pH- and redox-sensitive were formed only from PMMA-AA copolymers. MMA is the optimal hydrophobic monomer, whereas the use of various COOH-containing monomers, e.g., MAA and AA, will always induce a pH-triggered physical gelation. The PMMA-AA gels were prepared at physiological pH range from concentrated dispersions of swollen, hollow, polymer-based particles cross-linked with either cystamine (CYS) or 3,3'-dithiodipropionic acid dihydrazide (DTP). A linear relationship between particle swelling ratios, gel elasticity, and ductility was observed. The PMMA-AA gels with lower AA contents feature lower swelling ratios, mechanical strengths, and ductilities. Increasing the swelling ratio (e.g., through increasing AA content) decreased the intraparticle elasticity; however, intershell contact and gel elasticity were found to increase. The mechanical properties and performance of the gels were tuneable upon varying the copolymers' compositions and the structure of the cross-linker. Compared to PMMA-AA/CYS, the PMMA-AA/DTP gels were more elastic and ductile. The biodegradability and cytotoxicity of the new hollow particle gels were tested for the first time and related to their composition, mechanical properties, and morphology. The new PMMA-AA/CYS and PMMA-AA/DTP gels have shown good biocompatibility, biodegradability, strength, and interconnected porosity and therefore have good potential as a tissue repair agent.

show abstract

Section: ■ Experimental Sectionmentioning

confidence: 98%

Injectable Biocompatible and Biodegradable pH-Responsive Hollow Particle Gels Containing Poly(acrylic acid): The Effect of Copolymer Composition on Gel Properties

et al. 2014

View full text Add to dashboard Cite

show abstract

“…16 Hole-shell and crescent-moon-shaped microparticles can be synthesised from acorn-shaped biphasic droplets by polymerisation of one of the phases. 17,18 Such unique morphologies can modify drug release profile 12,19,20 and increase the potential for alternative routes of drug administration.…”

Section: Introductionmentioning

confidence: 99%

Structured Biodegradable Polymeric Microparticles for Drug Delivery Produced Using Flow Focusing Glass Microfluidic Devices

Ekanem

Nabavi

Vladisavljević

et al. 2015

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Biodegradable poly(DL-lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) microparticles with tunable size, shape, internal structure and surface morphology were produced by counter-current flow focusing in axisymmetric (3D) glass capillary devices. The dispersed phase was composed of 0.5-2 wt% polymer solution in a volatile 2 organic solvent (ethyl acetate or dichloromethane) and the continuous phase was 5 wt% aqueous poly(vinyl alcohol) solution. The droplets with a coefficient of variation in dripping regime below 2.5 % were evaporated to form polymeric particles with uniform sizes ranging between 4-30 µm. The particle microstructure and surface roughness were modified by adding nanofiller (montmorillonite nanoclay) or porogen (2-methylpentane) in the dispersed phase to form less porous polymer matrix or porous particles with golf-ball-like dimpled surface, respectively. The presence of 2-4 wt% nanoclay in the host polymer significantly reduced the release rate of paracetamol and prevented the early burst release, as a result of reduced polymer porosity and tortuous path for the diffusing drug molecules. Numerical modelling results using the volume of fluid-continuum surface force model agreed well with experimental behaviour and revealed trapping of nanoclay particles in the dispersed phase upstream of the orifice at low dispersed phase flow rates and for 4 wt% nanoclay content, due to vortex formation. Janus PLA/PCL (polycaprolactone) particles were produced by solvent evaporation-induced phase separation within organic phase droplets containing 3 % (v/v) PLA/PCL (30/70 or 70/30) mixture in dichloromethane. A strong preferential adsorption of Rhodamine 6G dye onto PLA was utilized to identify PLA portions of the Janus particles by Confocal Laser Scanning Microscopy (CLSM). Uniform hemispherical PCL particles were produced by dissolution of PLA domes with acetone.

show abstract

“…[ 25 ] The golf-ball-structure is one of the most important types of textured particles, containing a wrinkled spherical shell [ 26 ] to give 3D honeycomb-shaped fi lms. Recently, we have reported the development of facile methods to prepare golf-ball-shaped microparticles [ 27 ] showing improved cell internalization [ 28 ] and cell adhesion [ 22 ] for small-and large-sized dimple-structured microparticles, respectively. We therefore selected uniformly sized golf-ball-shaped microparticles for the preparation of the opal structure.…”

Section: Resultsmentioning

confidence: 99%

“…The initial stage in the preparation of these uniformly sized smooth microspheres and golf-ball-shaped microparticles involved their synthesis from a tubing-based microfl uidic apparatus using the amorphous polymers poly(D,L-lactic-co -glycolic acid) (PLGA) and poly(D,L-lactic acid) (PDLA) at 18 °C, as previously reported ( Figure S1, Supporting Information). [ 27 ] We selected an amorphous biodegradable polymer because of its wide-ranging uses in biomedical applications. A slight difference in the dimple structure was observed depending on the materials used.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Inverse Opal Scaffolds with an Embossed Surface Pattern Prepared from Sticky Golf‐Ball‐Shaped Microparticle Assemblies

Kim

Lee

et al. 2015

Adv Materials Inter

Self Cite

View full text Add to dashboard Cite

coherent light collection in photonic crystals, high speed ion and electron movement in separators [ 5 ] and electrodes [ 6,7 ] of lithium-ion batteries, and microfi ltration membranes. [ 8 ] In tissue engineering, 3D porous scaffolds are critical for providing multidirectional physical supports for cell attachment. Interconnected pores within the scaffolds play an important role in cell migration, the supply of nutrients and oxygen, and the removal of waste metabolites. In addition, it has been reported that pore size should ideally be large enough to promote cell seeding and ingrowth. A number of attempts to yield larger pores (normal cell size 20-100 µm) in scaffolds using methods such as gas in liquid foam templating, [ 9 ] salt leaching, and freeze drying [ 10 ] have been reported.[ 11 ] However, these methods result in random pore sizes, shapes, and generally yield disordered structures. Because pore size, shape, and interconnectivity [ 12 ] have a signifi cant impact on tissue engineering, a scaffold that provides optimum levels of each is required. [ 13 ] The inverse opal structure has been found to be an ideal scaffold for cell cultures owing to its regular 3D interconnectivity, and its uniform pore size within a critical range, which promotes cell seeding and ingrowth, and plays a vital role in cell culture. [ 14 ] To date, a range of biomedical applications have been studied using inverse opal scaffolds, such as immune cell culture, cell body formation, neovascularization, bone cartilage formation, and neural tissue engineering. [14][15][16] While inverse opal structures can be applied in a range of fi elds where smaller pore sizes are required, those bearing larger pores are essential for providing comparative pore sizes for the cells in scaffold applications. However, reduction in the surface-area-to-volume ratio (SAV) in these systems may reduce the surface area available for cell adhesion. Compensation of the surface area in bigger pore size applications should therefore be considered, and new approaches are required.Physical parameters such as surface topography, roughness, and elasticity have recently been reported to infl uence cell interactions with a 2D fl at substrate. [ 17 ] For example, a fi lm surface with microgrooves is capable of inducing cell alignment and myotube formation. [ 18 ] In addition, 3D micro pillar structures on polydimethylsiloxane (PDMS) fi lm surfaces demonstrate Inverse opal scaffolds presenting an embossed-pattern surface are prepared from colloidal crystal assemblies of uniformly sized golf-ball-shaped microparticles. Post-treatments, such as thermal annealing during the bridging of the microparticles for opal preparation, are avoided to prevent deterioration of surface patterns of the sacrifi cial template. This presents a new approach to increase the surface-area-to-volume ratio (SAV) by the alteration of morphological features in sophisticated 3D structures that remain largely unexamined owing to diffi culties in their preparation. Previous results observed in 2D ...

show abstract

Facile fabrication of uniform golf-ball-shaped microparticles from various polymers

Cited by 41 publications

References 40 publications

Injectable Biocompatible and Biodegradable pH-Responsive Hollow Particle Gels Containing Poly(acrylic acid): The Effect of Copolymer Composition on Gel Properties

Injectable Biocompatible and Biodegradable pH-Responsive Hollow Particle Gels Containing Poly(acrylic acid): The Effect of Copolymer Composition on Gel Properties

Structured Biodegradable Polymeric Microparticles for Drug Delivery Produced Using Flow Focusing Glass Microfluidic Devices

Inverse Opal Scaffolds with an Embossed Surface Pattern Prepared from Sticky Golf‐Ball‐Shaped Microparticle Assemblies

Contact Info

Product

Resources

About