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A new fluorescent sensor, 4-allylamine-N-(N-salicylidene)-1,8-naphthalimide (1), anchoring a naphthalimide moiety as fluorophore and a Schiff base group as receptor, was synthesized and characterized. The photophysical properties of sensor 1 were conducted in organic solvents of different polarities. Our study revealed that, depending on the solvent polarity, the fluorescence quantum yields varied from 0.59 to 0.89. The fluorescent activity of the sensor was monitored and the sensor was consequently applied for the detection of Cu with high selectivity over various metal ions by fluorescence quenching in Tris-HCl (pH = 7.2) buffer/DMF (1:1, v/v) solution. From the binding stoichiometry, it was indicated that a 1:1 complex was formed between Cu and the sensor 1. The fluorescence intensity was linear with Cu in the concentration range 0.5-5 μM. Moreso, the detection limit was calculated to be 0.32 μM, which is sufficiently low for good sensitivity of Cu ion. The binding mode was due to the intramolecular charge transfer (ICT) and the coordination of Cu with C = N and hydroxyl oxygen groups of the sensor 1. The sensor proved effective for Cu monitoring in real water samples with recovery rates of 95-112.6 % obtained.

Three mono-, bi- and multi-nuclear Ag(i) complexes have been synthesized and characterized systematically. The complexes bind to DNA in a intercalate mode. Complex2has the potential ability to scavenge hydroxyl radicals inin vitrostudies.

Super-resolution microscopy (SRM) has revolutionized cell biology, enabling visualization of cellular structures with nanometric resolution, single-molecule sensitivity, and with multiple colors. Here we review how nanocontainers have been used to enhance these techniques.

A new fluorescent Al 3+ -probe, N-allyl-4-[3,3′-((2-aminoethyl)

The present study reports the development of a new 1,8-naphthalimide-based fluorescent sensor V for monitoring Cu(II) ions. The sensor exhibited pH independence over a wide pH range 2.52-9.58, and indicated its possible use for monitoring Cu(II) ions in a competitive pH medium. The sensor also showed high selectivity and sensitivity towards the Cu(II) ions over other competitive metal ions in DMSO-HEPES buffer (v/v, 1:1; pH 7.4) with a fluorescence 'turn off' mode of 79.79% observed. A Job plot indicated the formation of a 1:1 binding mode of the sensor with Cu(II) ions. The association constant and detection limit were 1.14 × 10 M and 4.67 × 10 M, respectively. The fluorescence spectrum of the sensor was quenched due to the powerful paramagnetic nature of the Cu(II) ions. Potential application of this sensor was also demonstrated when determining Cu(II) ion levels in two different water samples.

Though it has not been shown to deliver any biological importance, mercuric(II) ion (Hg 2+) is a deleterious cation which poses grievous effects to the human body and/or the ecosystem, hence, the need for its sensitive and selective monitoring in both environmental and biological systems. Over the years, there has been a great deal of work in the use of fluorescent, colourimetric, and/or ratiometric probes for Hg 2+ recognition. Essentially, the purpose of this review article is to give an overview of the advances made in the constructions of such probes based on the works reported in the period from 2011 to 2019. Discussion in this review work has been tailored to the kinds of fluorophore scaffolds used for the constructions of the probes reported. Selected examples of probes under each fluorophore subcategory were discussed with mentions of the typically determined parameters in an analytical sensing operation, including modulation in fluorescence intensity, optimal pH, detection limit, and association constant. The environmental and biological application ends of the probes were also touched where necessary. Important generalisations and conclusions were given at the end of the review. This review article highlights 196 references. Keywords Mercuric(II) ion (Hg 2+) • Fluorescent probes • Colourimetric probes • Ratiometric probes • Hg 2+-selective probes • Sensing

From the structure of DNA, [1] to computer science, [2] and space-station batteries, [3] several key scientific discoveries that enhance our lives today,w ere made by marginalized scientists.T hese three scientists,R osalind E. Franklin, Alan M. Turing and Olga D. Gonzµlez-Sanabria, did not conform to the cultural expectations of how scientists should look and behave.U nfortunately,m arginalized scientists are often viewed as just aresource rather than the lifeblood that constitutes science itself.W eneed to embrace scientists from all walks of life and corners of the globe;t his will also mean that nobody is excluded from tackling the life-threatening societal challenges that lie ahead. An awareness of science policy is essential to safeguarding our future.