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Heavy atom free organic materials absorbing in red to near infrared (NIR) region are potential candidates as photosensitizers (PS) in photodynamic therapy (PDT). PDT relies on many factors and one of them is singlet oxygen generation ability of PS in aqueous medium. In this contribution, we report the synthesis of a new PS i. e. 8‐thienyl bisbenzothieno‐[b]‐fused‐boron‐dipyrromethene (BT‐[b]‐fused BODIPY). This PS shows absorption (λabs) at ~650 nm in toluene while in its water‐dispersible nanoaggregates it is found at ~764 nm. Nanoaggregates of BT‐[b]‐fused BODIPY demonstrated dual advantages, (i) facilitating PS release in the cellular system and (ii) sharply enhanced singlet oxygen efficiency (ΦΔ ${\Phi _{\rm{\Delta }} }$ ~48 %) in aqueous medium. Intracellular reactive oxygen species (ROS) generation was confirmed by 2′,7′‐dichlorodihydrofluorescein diacetate (DCFDA) assay in A549 cells. In vitro photocytotoxic studies of BT‐[b]‐fused BODIPY are carried out in different carcinomas i. e. MCF‐7 and A549 cells. It has zero dark cell toxicity while half maximal inhibitory concentration (IC50) in MCF‐7 is found to be low (6.08±1.1) μM and 7.41±1.9 μM in A549 on 15 min light exposure. These nanoaggregates induce apoptosis in cancer cells on light irradiation thereby proving it to be a potential PS for PDT. [ABSTRACT FROM AUTHOR]

In this research work, different chemical modifications were applied to gold nanoparticles and their use in enhanced non-classical light emitters based on metal-enhanced fluorescence (MEF) was evaluated. In order to achieve this, gold core–shell nanoparticles with silica shells were modified via multilayered addition and the incorporation of a covalently linked laser dye to develop MEF. Their inter-nanoparticle interactions were evaluated by using additional silica shell multilayers and modified cyclodextrin macrocycles. In this manner, the sizes and chemical surface interactions on the multilayered nanoarchitectures were varied. These optical active nanoplatforms led to the development of different nanoassembly sizes and luminescence behaviors. Therefore, the interactions and nanoassembly properties were evaluated by using various spectroscopic and nanoimaging techniques. Highly dispersible gold core–shell nanoparticles with diameters of 50–60 nm showed improved colloidal dispersion that led to single ultraluminescent gold core–shell nanoparticles with MEF. Then, the addition of variable silica lengths produced increased interactions and consequent nanoaggregation. However, the silanized nanoparticles were easily dispersible after agitation or sonication. Thus, their sizes were proportional only to the diameter and the van de Waals interaction did not affect their sizes in bulk. Then, the covalent linking of different concentrations of modified cyclodextrins was applied to the chemical surfaces by incorporating additional hydroxyl groups from the glucose monomeric unities of cyclodextrins. In this manner, variable larger-sized and inter-branched grafted gold core–shell silica nanoparticles were generated. The ultraluminescent properties were conserved due to the non-optical activity of the cyclodextrins. However, they generated enhanced ultraluminescence phenomena. Laser fluorescence microscopy nanoimaging showed enhanced resolutions in comparison to non-grafted supramolecular gold core–shell nanoparticles. The differences in their interactions and the sizes of the nanoassemblies were explained by their single nanoparticle diameters and the interacting chemical groups on their nanosurfaces. While the varied luminescence emissions generated were tuned by plasmonics, enhanced plasmonic phenomena and light scattering properties were seen depending on the type of nanoassembly. Thus, optically active and non-optically active materials led to different optical properties in the bright field and enhanced the excited state within the electromagnetic near-field of the gold nanotemplates. In this manner, it was possible to achieve high sensitivity by varying the spacer lengths and optical properties. Therefore, further perspectives regarding the design of nano-tools composed of light for various applications were discussed. [ABSTRACT FROM AUTHOR]

Solar energy is a natural renewable energy source. The sunlight that spreads the earth's atmosphere is sufficient to power all of our essentials. The real-world usage of solar energy is critical to fulfilling current and future needs. This article focuses on the vital use of solar energy by utilizing the nanoaggregation concept. A suitable mathematical model is established by considering the flow slip, hydrodynamics, Ohmic, and radiative heats. The modeled problem was resolved using R-K-based shooting process. Simultaneous outcomes are obtained for the aggregation and nonaggregation cases. This study is a practical application of enhanced heat transport in Parabolic Trough Solar Collector (PTSC). It is found that nanoparticle aggregation aids in enlarging the thermal conduction rate of PTSC. This helps with the practical usage of solar energy. [ABSTRACT FROM AUTHOR]

• An AIE active anthracene-based Schiff base probe ' AP' is firstly reported as Cu2+ sensor. • AP has negligible interfering effect on Cu2+ detection with nanomolar LOD. • AP - AP * in AIE and AP − Cu2+ − AP * excimer formation is established from UV/PL, DFT and 1H NMR titration debriefings. • Crystalline and nanostructural features of AIE and sensors are authorized by PXRD, SEM, TEM and DLS studies. • Proposed method is validated by cellular imaging and real water recovery interrogations. An aggregation induced emission (AIE) active anthracene-based Schiff base probe "(2-((anthracen-9-ylmethylene) amino) phenol); AP " was synthesized via one-pot reaction and utilized in "turn-on" detection of Cu2+ ions. Ultraviolet–visible and photoluminescence (UV–vis/PL) interrogations confirm the AIE between 0 and 99 % water fraction (f w) and high selectivity of AP to Cu2+. PL studies establish the linear regression of Cu2+ between 0 and 24 µM with a detection limit (LOD) of 53.2 nM. The Job plot and high-resolution mass (HR-mass) data affirm 2:1 stoichiometry and the association constant (K a) value appraised as 1.88 × 10−4 M−2. Time-resolved photoluminescence (TRPL) studies reveal decay kinetics of AIE, Cu2+ sensors and complex's reversibility. Moreover, 1H NMR titration and density functional theory (DFT) investigations identify the binding mode, π-π stacking in AIE, AP − Cu2+ − AP * excimer formation, band gap variations and involvement of photoinduced electron transfer (PET) and chelation enhanced fluorescence (CHEF) mechanism. Crystallinity and nanostructural variations of AIE and Cu2+ sensors are investigated by using powder-X-ray diffraction (PXRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and dynamic light scattering (DLS). AIE and Cu2+ sensory method are validated by MDA-MB-231 cellular imaging studies. Finally, real water-based titrations show nanomolar LODs and recoveries > 97 % with RSDs < 3.5 %. [ABSTRACT FROM AUTHOR]

The discovery and synthesis of novel multifunctional organic building blocks for nanoparticles is challenging. Texaphyrin macrocycles are capable and multifunctional chelators. However, they remain elusive as building blocks for nanoparticles because of the difficulty associated with synthesis of texaphyrin constructs capable of self-assembly. A novel manganese (Mn)-texaphyrin-phospholipid building block is described, along with its one-pot synthesis and self-assembly into a Mn-nanotexaphyrin. This nanoparticle possesses strong resilience to manganese dissociation, structural stability, in vivo bio-safety, and structure-dependent T1 and T2 relaxivities. Magnetic resonance imaging (MRI) contrast enhanced visualization of lymphatic drainage is demonstrated with respect to proximal lymph nodes on the head and neck VX-2 tumors of a rabbit. Synthesis of 17 additional metallo-texaphyrin building blocks suggests that this novel one-pot synthetic procedure for nanotexaphyrins may lead to a wide range of applications in the field of nanomedicines. [ABSTRACT FROM AUTHOR]

Tetraphenylethene and doxorubicin are assembled into a self-indicating drug delivery system (TD NPs). TD NPs are decomposed into DOX and TPE NPs in lysosome. Since TD NPs, TPE NPs and DOX are all fluorescent, the detachment of DOX from TPE NPs is accompanied by fluorescence changing. By observing the fluorescence changes, the spatiotemporal drug release is visualized., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)