Designer hydrophilic regions regulate droplet shape for controlled surface patterning and 3D microgel synthesis.

Small

Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 65 Landsdowne Street, Cambridge, MA 02139, USA.

Published: February 2012


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

A simple technique is presented for controlling the shapes of micro- and nanodrops by patterning surfaces with special hydrophilic regions surrounded by hydrophobic boundaries. Finite element method simulations link the shape of the hydrophilic regions to that of the droplets. Shaped droplets are used to controllably pattern planar surfaces and microwell arrays with microparticles and cells at the micro- and macroscales. Droplets containing suspended sedimenting particles, initially at uniform concentration, deposit more particles under deeper regions than under shallow regions. The resulting surface concentration is thus proportional to the local fluid depth and agrees well with the measured and simulated droplet profiles. A second application is also highlighted in which shaped droplets of prepolymer solution are crosslinked to synthesize microgels with tailored 3D geometry.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3285541PMC
http://dx.doi.org/10.1002/smll.201101745DOI Listing

Publication Analysis

Top Keywords

hydrophilic regions
12
shaped droplets
8
regions
5
designer hydrophilic
4
regions regulate
4
regulate droplet
4
droplet shape
4
shape controlled
4
controlled surface
4
surface patterning
4

Similar Publications

Impact of wettability heterogeneity on methane hydrate growth kinetics in partially water-saturated sediments.

J Colloid Interface Sci

August 2025

Research Centre of Ecology & Environment for Coastal Area and Deep Sea, Guangdong University of Technology, Guangzhou 510006, China; Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou),

Hypothesis: Gas hydrate formation in sediments is influenced by the availability of gas-water interfacial areas, which governs gas-water interactions. The surface wettability of sediment particles is expected to affect the spatial distribution of water within the pore space, thereby altering the extent of gas-liquid contact. Consequently, by tuning the wettability heterogeneity of the sediment, the spatial distribution of pore water can be regulated, which in turn influences the gas-water interactions and the kinetics of gas hydrate formation.

View Article and Find Full Text PDF

Proto-SLIPS: Slippery Liquid-Infused Surfaces that Release Highly Water-Soluble Agents.

ACS Appl Mater Interfaces

September 2025

Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706, United States.

Slippery liquid-infused porous surfaces (or "SLIPS") can prevent bacterial surface fouling, but they do not inherently possess the means to kill bacteria or reduce cell loads in surrounding media. Past reports show that the infused liquids in these materials can be leveraged to load and release antimicrobial agents, but these approaches are generally limited to the use of hydrophobic agents that are soluble in the infused oily phases. Here, we report the design of so-called "proto-SLIPS" that address this limitation and permit the release of highly water-soluble (or oil-insoluble) agents.

View Article and Find Full Text PDF

Light-activated antimicrobial polymers with citronellol-enhanced bacterial accumulation for on-demand disinfection.

J Mater Chem B

September 2025

School of Materials Science and Engineering, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou, 510640, China.

Antibacterial photodynamic therapy offers a promising approach for combating both susceptible and multidrug-resistant pathogens. However, conventional photosensitizers have limitations in terms of poor binding specificity and weak penetration for pathogens. In this study, we developed synergistic photobactericidal polymers that integrate hydrophilic toluidine blue O (TBO) with the lipophilic penetration enhancer citronellol (CT).

View Article and Find Full Text PDF

Photodegradable nanoparticles with sphere, worm, and vesicle morphologies were synthesized following polymerization induced self-assembly (PISA), incorporating a photoresponsive phenyl vinyl ketone (PVK) block and a nonphoto responsive 2-hydroxypropyl methacrylamide (HPMA) block. The photodegradation of nanoparticles under UV revealed that the initial shapes of sphere and vesicle particles are retained even until 7 h and after 24 h of photo-induced degradation, respectively, despite a significant reduction in molecular weight (M). This could be due to the assembly of degraded PVK fragments in the hydrophobic region, maintaining the relative hydrophilic to hydrophobic ratio.

View Article and Find Full Text PDF

Optimization and application of pretreatment for the analysis of typical per- and polyfluoroalkyl substances (PFAAs) in drinking water: a systematic evaluation of filter membranes and SPE Sorbents.

Anal Sci

September 2025

Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Resources and Environment, Nanchang University, Nanchang, 330031, People's Republic of China.

The accurate detection of trace perfluoroalkyl acids (PFAAs) in drinking water remains challenging due to nonspecific adsorption losses during pretreatment. This study systematically evaluated the adsorption behaviors of 11 PFAAs across five filtration membranes and four solid-phase extraction (SPE) sorbents to establish an optimized analytical protocol. Results demonstrated that glass fiber (GL) filters minimized PFAAs retention (94.

View Article and Find Full Text PDF