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Asymmetric ultrafiltration membranes derived from block copolymer self-assembly have seen growing attention as a result of their ordered pore structures and scalable fabrication process. One route to extend their utility is to provide, through the molecular architecture of the block copolymer, covalent binding sites for facile attachment of foreign functional molecules. Here, we report the synthesis of triblock terpolymer poly(styrene)-block-poly(4-vinylpyridine)-block-poly(propylene sulfide) (SVPS) and its fabrication into isoporous ultrafiltration membranes. Final SVPS membrane top surfaces exhibit narrowly dispersed mesopores with 6-fold symmetry. Membranes show a switchable response to pH changes demonstrating the potential as a chemical gate. Membrane pore surfaces are decorated with thiol groups providing active covalent binding sites via versatile thiol–ene click chemistry. The work may open pathways to produce high-performance multifunctional membranes for chem- and bio-sensing and for separation ...

Change history: In Fig. 3b of this Letter, the labels for the outer (11.8 nm) and inner (7.4 nm) diameters of the structure were inadvertently omitted. Fig. 3 has been corrected online.

Silica chemistry provides pathways to uniquely tunable nanoparticle platforms for biological imaging. It has been a long-standing problem to synthesize fluorescent silica nanoparticles (SNPs) in batch reactions with high and low fluorescence intensity levels for reliable use as an intensity barcode, which would greatly increase the number of molecular species that could be tagged intracellularly and simultaneously observed in conventional fluorescence microscopy. Here, employing an amino-acid catalyzed growth, highly fluorescent SNP probes were synthesized with sizes < 40 nm and well separated intensity distributions, as mapped by single-particle imaging techniques. A seeded growth approach was used to minimize the rate of secondary particle formation. Organic fluorescent dye affinity for the SNP during shell growth was tuned using specifics of the organosilane linker chemistry. This work highlights design considerations in the development of fluorescent probes with well separated intensity distributions synthesized in batch reactions for single-particle imaging and sensing applications, where heterogeneities across the nanoparticle ensemble are critical factors in probe performance.

Silica chemistry provides pathways to uniquely tunable nanoparticle platforms for biological imaging. It has been a long-standing problem to synthesize fluorescent silica nanoparticles (SNPs) in batch reactions with high and low fluorescence intensity levels for reliable use as an intensity barcode, which would greatly increase the number of molecular species that could be tagged intracellularly and simultaneously observed in conventional fluorescence microscopy. Here, employing an amino-acid catalyzed growth, highly fluorescent SNP probes were synthesized with sizes