The bioconjugation of DNA with gold nanoparticles towards the spectrophotometric genosensing of pathogenic bacteria

The investigation of important bio-molecular events such as expression of special genes has shown promise with the advent of nanotechnology.

Tuning the Biginelli reaction mechanism by the ionic liquid effect: the combined role of supported heteropolyacid derivatives and acidic strength

Herein, a combination of heteropolyacids and ionic liquids as a catalytic system was studied for the Biginelli multicomponent reaction; the positive ionic liquid effect associated with the acidic strength of zeolite-supported heteropolyacids made this combination an efficient catalytic system for the multicomponent synthesis of 3,4-dihydropyrimidin-2(1H)-one/thione derivatives. The acidic strength effect was evaluated, and a range was determined in which the reaction provided better results. The mechanism of the reaction was also investigated in the presence and absence of ionic liquids, and two features of paramount importance were revealed: the mechanism could be tuned to proceed through only one reaction path among three possibilities and the kinetics of the reaction was significantly faster in the presence of an ionic liquid.

Heteropolyacids and ionic liquid effect allowed tuning of the Biginelli reaction mechanism and synthesis of 3,4-dihydropyrimidin-2(1H)-one/thione derivatives in an efficient, recyclable fashion. The role of acidic strength and supported heteropolyacid is disclosed.

A perylenediimide-based nanocarrier monitors curcumin release with an “off–on” fluorescence switch

A perylenediimide-based nanocarrier (PPL-B) is constructed and used for monitoring curcumin release through an “off–on” fluorescence switch.

Methyl-restricted rotor rotation on the stator produces high-efficiency fluorescence emission: a new strategy to achieve aggregation-induced emission

At present, we have realized that the aggregation-induced emission (AIE) achieves the purpose of fluorescence enhancement by restricting rotations to reduce intermolecular or intramolecular energy loss. Based on this idea, we synthesized a novel fluorene-based fluorescent compound with a restricted rotor rotation on the stator through the Suzuki coupling reaction. The luminescence effect was evaluated by comparing its fluorescence intensity with that of the control compound. Finally, theoretical calculations showed that the presence of methyl groups hindered the thermal rotation of the fluorenyl groups. Thus, the results indicated that the fluorescence of this compound was better than that of the control compound. A new synthetic pathway for high-efficiency AIE-based fluorescent luminogens has been developed.

At present, we have realized that the aggregation-induced emission (AIE) achieves the purpose of fluorescence enhancement by restricting rotations to reduce intermolecular or intramolecular energy loss.

Tuning the aggregation performance by varying the substituent position: comparative study of neutral bis-urea derivatives in aqueous medium

A set of three neutral bis-urea derivatives has been purposefully chosen to investigate the consequences of positional isomers on the aggregation performance.

Microwave-assisted facile synthesis of poly(luminol-co-phenylenediamine) copolymers and their potential application in biomedical imaging

Conjugated copolymers have attracted much attention because of their outstanding photo-physical properties. The present work reports for the first time, microwave-assisted copolymerization of o-phenylenediamine with luminol using different weight ratios of the two monomers. The composition of the copolymers was confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (¹H-NMR) while monomer reactivity ratios were determined using the Fineman–Ross method. Ultraviolet-visible spectroscopy revealed the variation in polaronic states upon copolymerization while X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses showed the morphology of the copolymers to be intermediate between that of the homopolymers. Confocal analysis and fluorescence studies revealed that the copolymers showed composition based blue as well as red emission which could be utilized for in vivo imaging of cancer cells.

Development of bioimaging agents based on poly(o-phenylendiamine and luminol).

Materials Functionalization with Multicomponent Reactions: State of the Art

The emergence of neoteric synthetic routes for materials functionalization is an interesting phenomenon in materials chemistry. In particular, the union of materials chemistry with multicomponent reactions (MCRs) opens a new avenue leading to the realm of highly innovative functionalized architectures with unique features. MCRs have recently been recognized as considerable part of the synthetic chemist's toolbox due to their great efficiency, inherent molecular diversity, atom and pot economy along with operational simplicity. Also, MCRs can improve E-factor and mass intensity as important green chemistry metrics. By rational tuning of the materials, as well as the MCRs, wide ranges of functionalized materials can be produced with tailorable properties that can play important roles in the plethora of applications. To date, there has not reported any exclusive review of a materials functionalization with MCRs. This critical review highlights the state-of-the-art on the one-pot functionalization of carbonaceous and siliceous materials, polysaccharides, proteins, enzymes, synthetic polymers, etc., via diverse kind of MCRs like Ugi, Passerini, Petasis, Khabachnik-Fields, Biginelli, and MALI reactions through covalent or noncovalent manners. Besides the complementary discussion of synthetic routes, superior properties and detailed applicability of each functionalized material in modern technologies are discussed. Our outlook also emphasizes future strategies for this unprecedented area and their use as materials for industrial implementation. With no doubt, MCRs-functionalization of materials bridges the gap between materials science domain and applied chemistry.

Functional Poly(dihalopentadiene)s: Stereoselective Synthesis, Aggregation-Enhanced Emission and Sensitive Detection of Explosives

The development of polymeric materials with novel structures and unique properties and functionalities is of both academic and industrial significance. In this work, functional poly(dihalopentadiene)s were synthesized by boron trihalide-mediated multicomponent polymerization routes in a stereoselective manner. The polymerizations of tetraphenylethylene-containing diyne, BX₃ (X = Cl, Br) and p-tolualdehyde proceed smoothly in dichloromethane under mild conditions to afford high molecular weight poly(dihalopentadiene)s with a predominant (Z,Z)-configuration in moderate to good yields. The reaction conditions and the boron trihalide used were found to have great effects on the stereochemistry of the resulting polymer structures. The obtained poly(1,5-dihalo-(Z,Z)-1,4-pentadiene)s possess high thermal stability and good film-forming ability. Their thin films show high refractive index of 1.9007⁻1.6462 in a wide wavelength region of 380⁻890 nm with low optical dispersion. The polymers are weakly emissive in dilute solutions but become highly emissive upon aggregated, demonstrating a unique phenomenon of aggregation-enhanced emission. Their nanoaggregates in aqueous media can serve as sensitive fluorescent chemosensors for the detection of explosives with a superamplification effect and a low detection limit.

A new blue AIEgen based on tetraphenylethene with multiple potential applications in fluorine ion sensors, mechanochromism, and organic light-emitting diodes

A new blue organoboron AIEgen with multiple potential applications is synthesized and studied.