A simple and highly efficient method for dopamine (DA) detection using water-soluble silicon nanoparticles (SiNPs) was reported. The SiNPs with a high quantum yield of 23.6% were synthesized by using a one-pot microwave-assisted method. The fluorescence quenching capability of a variety of molecules on the synthesized SiNPs has been tested; only DA molecules were found to be able to quench the fluorescence of these SiNPs effectively. Therefore, such a quenching effect can be used to selectively detect DA. All other molecules tested have little interference with the dopamine detection, including ascorbic acid, which commonly exists in cells and can possibly affect the dopamine detection. The ratio of the fluorescence intensity difference between the quenched and unquenched cases versus the fluorescence intensity without quenching (ΔI/I) was observed to be linearly proportional to the DA analyte concentration in the range from 0.005 to 10.0 μM, with a detection limit of 0.3 nM (S/N = 3). To the best of our knowledge, this is the lowest limit for DA detection reported so far. The mechanism of fluorescence quenching is attributed to the energy transfer from the SiNPs to the oxidized dopamine molecules through Förster resonance energy transfer. The reported method of SiNP synthesis is very simple and cheap, making the above sensitive and selective DA detection approach using SiNPs practical for many applications.

unique optical properties such as strong luminescence, high photostability, and size-tunable emission wavelength. [ 1 ] However, these semiconductor QDs usually have the problem of low biocompatibility. Thus it is urgent to fi nd alternative fl uorescent nanoparticles with similar optical properties. Silicon, the second most abundant element on earth, is nontoxic (or with low toxicity) and essential for human health. [ 2 ] Because of their superb electronic, optical, and mechanical properties, silicon-based nanostructures (such as nanospheres, nanoribbons, nanowires, nanorods, and nanodots) have been extensively employed in a large variety of applications, including those related to optoelectronics, energy, catalysis, bioanalysis, and biology. [ 3 ] With many superior characteristics including excellent optical properties, easy surface modifi cation capability, superb biocompatibility, and low cytotoxicity, fl uorescent silicon nanoparticles (SiNPs) are being considered as replacements for current fl uorescence labels in biological, biomedical, and biochemical applications, including longterm bioimaging [ 2c,d , 4 ] and sensing. [ 5 ] Numerous methods for preparing free-standing SiNPs have been developed and can be classifi ed into three categories: [ 6 ] (1) the top-down approach using bulk silicon materials (e.g., etching of bulk silicon [ 7 ] and breaking down silicon rich Fluorescent silicon nanoparticles (SiNPs) have shown potential applications in bioimaging/biolabelling, sensing, and nanomedicine/cancer therapy due to their superior properties such as excellent photostability, low cytotoxicity, and versatile surface modifi cation capability. Here, a simple, high-yield, and one-pot method is developed to prepare superbright, water-soluble, and amine-functionalized SiNPs with photoluminescence quantum yield (PLQY) comparable to fl uorescent II-VI semiconductor quantum dots (QDs) but with much lower cytotoxicity. By introducing a commercially available amine-containing silane molecule, N-[3-(trimethoxysilyl)propyl]ethylenediamine (DAMO), water-soluble SiNPs are prepared with PLQY of 82.4% via a microwave-assisted method. To the best of our knowledge, this is the highest PLQY value ever reported for water-soluble fl uorescent SiNPs. The silicon element in our SiNPs is mainly four-valent silicon and thus these SiNPs may also be termed as oxidized silicon nanospheres or silica nanodots. We have also demonstrated the importance of the silane structure (e.g., a suitable amine content) on the photoluminescence property of the prepared SiNPs. As revealed by the time-resolved photoluminescence technique, the highest PLQY value of DAMO SiNPs is correlated with their monoexponential decay with a relatively long fl uorescence lifetime. In addition, the potential use of these SiNPs has also been demonstrated for fl uorescent patterning/printing and ion sensing (including Cu 2+ and Hg 2+).

Hydrolysis of planar phospholipids catalyzed by honey bee venom phospholipase A (bvPLA) was studied. Experiments demonstrated that Ca ions mediated between the lipids and bvPLA, induced reorientation of bvPLA, and activated hydrolysis. One of the hydrolysis products, fatty acids, was desorbed, and the other one, lysophospholipids, self-organized at the interface.

A commercially available amine‐containing silane molecule, N‐[3‐(trimethoxysilyl)propyl]ethylenediamine (DAMO) is introduced in article 1500360 by F. G. Wu, Z. Chen, and co‐workers. Superbright water‐soluble silicon nanoparticles (SiNPs) are prepared with a photoluminescence quantum yield (PLQY) of 82.4% via a one‐pot microwave‐assisted method. To the best of the authors' knowledge, this is the highest PLQY value ever reported for water‐soluble fluorescent SiNPs.

No abstract