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We, the Editor and Publisher of the journal Supramolecular Chemistry, have retracted the following article: Tanuja Yeluri, Rajesh S. Bhosale, Namdev V. Ghule, Aaron M. Raynor, Sidhanath V. Bhosale & Sheshanath V. Bhosale (2015) Neomycin and gentamic in detection via molecular recognition with cyclam-decorated gold nanoparticles, Supramolecular Chemistry, 27:11-12, 772-779, DOI: 10.1080/10610278.2015.1071819 Since publication, significant concerns have been raised about the integrity of data and figures in the article. When approached for an explanation, the corresponding author did not provide the requested supporting information. RMIT University, where research had been conducted, confirm they are investigating issues related to the integrity of the published work. As verifying the validity of published work is core to the integrity of the scholarly record, we are therefore retracting the article. The institution and the corresponding author have been informed. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted articles will remain online to maintain the scholarly record, but they will be digitally watermarked on each page as ‘Retracted’.

Herein we describe the development of cyclam-coated gold nanoparticles (cyclam-Au NPs) based sensitive colorimetric method for neomycin and gentamicin detection. The cyclam-Au NPs were characterised by UV–vis spectroscopy, fourier transform infrared spectroscopy, transmission electron microscopy techniques, dynamic light scattering and zeta potential measurements. The cyclam-Au NPs aggregated in presence of neomycin and gentamicin, which results a colour change from violet to blue. The characteristic absorption peak at 530 nm was bathochromic-shifted to a longer wavelength (660 nm). This confirms the aggregation of cyclam-Au NPs in the presence of neomycin as well as gentamicin via hydrogen bonding. The UV–vis absorption measurements employed to determine detection limit of neomycin and gentamicin. The detection limit is 1.87 × 10− 8 M and 2.35 × 10− 8 M for neomycin and gentamicin respectively.

Retraction of ‘Dipyrrolyl-bis-sulfonamide chromophore based probe for anion recognition’ by Namdev V. Ghule et al., RSC Adv., 2014, 4, 27112–27115, https://doi.org/10.1039/C4RA04000G.

Retraction of ‘Hydrogen sulfate ion sensing in aqueous media based on a fused pyrimido benzothiazole derivative’ by Sachin D. Padghan et al., RSC Adv., 2016, 6, 34376–34380, https://doi.org/10.1039/C6RA01980C.

The evaluation of basin from the drainage morphometric parameters helps in understanding the physical behaviour of the catchments for various purposes. Remote Sensing and Geographic Information System (GIS) techniques were used to study quantitative morphometric analysis of the Yerla River basin of basaltic Deccan Trap region, India. Morphometric analysis is carried out using Survey of India topographical maps in ArcGIS software. Thematic maps such as drainage map, stream ordering map, contour map, elevation map, slope map, aspect map and digital elevation model (DEM) are prepared. SRTM data of 90 m spatial resolution is used to create DEM and ASTER data of 30 m spatial resolution is used to create longitudinal profile of the catchment area. Various linear, relief and areal morphometric parameters such as area, perimeter, stream order, stream length, stream number, bifurcation ratio, drainage density, stream frequency, drainage texture, length of basin, form factor, circulatory ratio and elongation ratio are computed. The dendritic type drainage network of the basin exhibits the homogeneity in texture and lack of structural control. The seventh order basin has low drainage density and poor stream frequency indicates coarse drainage. The mean bifurcation ratio indicates a hilly dissected basin. The form factor ratio and circularity ratio shows that the whole basin has an elongated shape. The compactness coefficient value shows less hazardous basin. Sinuosity indices value indicate transitional stage. Morphometric analysis helps to understand the geo-hydrological characteristics of the watershed. It is inevitable in development and management of drainage basin.

Correction for ‘Dipyrrolyl-bis-sulfonamide chromophore based probe for anion recognition’ by Namdev V. Ghule et al., RSC Adv., 2014, 4, 27112–27115, DOI: 10.1039/C4RA04000G.

A series of new unsymmetrically substituted naphthalenediimide (NDI) moieties NDI‐1 to NDI‐6 were synthesized. The structures of these compounds were confirmed by means of FT‐IR, 1H NMR, 13C NMR, ESI‐mass and HRMS spectroscopic measurements. UV/Vis and fluorescence spectroscopy were employed to investigate the photophysical properties of the prepared compounds in solution and in the solid state. Using the onset of UV/Vis absorption, the optical band gaps were calculated. Cyclic voltammetry measurements were performed to study the electrochemical behavior and to calculate the LUMO energy levels. The thermal properties of NDI derivatives were studied by differential scanning calorimetry. The mesomorphic birefringent behavior of the NDI derivatives was investigated with polarizing optical microscopy. Among all of the studied NDI derivatives, only NDI‐1, NDI‐2, and NDI‐3 showed liquid crystalline texture, owing to the presence of an amide linkage for H‐bonding along with aromatic moieties for π–π‐stacking.

Correction for ‘Wheel like supramolecular assembly of cyclam decorated gold nanoparticles induced by Cd2+’ by Tanuja Yeluri et al., RSC Adv., 2015, 5, 21511–21514, DOI: 10.1039/C5RA00777A.

In the present work, two new naphthalene diimide (NDI) amphiphiles, NDI‐N and NDI‐NA, were successfully synthesized and employed to investigate their self‐assembly and optical properties. For NDI‐NA, which contains an amide group, aggregation‐induced emission enhancement (AIEE) was demonstrated in the presence of various ratios of methylcyclohexane (MCH) in chloroform, which led to the visual color changes. This new amide‐containing NDI‐NA amphiphile formed nanobelt structures in chloroform/MCH (10:90, v/v) and microcup‐like morphologies in chloroform/MCH (5:95, v/v). The closure of these microcups led to the formation of vesicles and microcapsules. The structural morphologies gained from the solvophobic control of NDI‐NA were confirmed by various complementary techniques such as infrared spectroscopy, X‐ray diffraction, and scanning and transmission electron microscopy. In the absence of the amide moiety in NDI‐N, no self‐assembly was observed, indicating the fundamental role of H‐bonding in the self‐association process.

A naphthalenediimide colorimetric pH sensor was designed, synthesised and employed for live cell applications. In DMSO : buffer solution, the NDI probe exhibits good pH selectivity and high photostability. We used a core-substituted naphthalenediimide (NDI-C) probe for the analysis of the autophagosomes. A new flow cytometric method was also developed for the analysis of cell population on the basis of intracellular pH.

A sensitive and selective receptor 3-cyano-4-imino-2-methylthio-4H-pyrimido[2,1-b][1,3]benzothiazole (SVK-1) bearing a fused pyrimido benzothiazole structure was developed for the recognition of HSO4− anions. UV-vis and fluorescence emission spectroscopy were employed for the recognition for HSO4− over other anions such as Cl−, Br−, I−, F−, AcO−, H2PO4−, ClO4− and NO3− in an aqueous medium.

This study presents a gold nanoparticle (Au NP) system based on interaction between cyclam and Au NPs. We have found that in the presence of Cd2+, cyclam coated Au NPs form well defined wheel like supramolecular assembled nanostructures. Self-assembly is achieved via co-ordination bonding between cyclam decorated Au NPs and Cd2+ ions. This finding introduces novel assembled nanostructures and contributes to understand the effect of Cd2+ cyclam interaction on the morphology of Au NPs assembly.

An amino-core-substituted naphthalenediimide (NDI) derivative has been synthesized in good yield in two steps. The NDI bearing a diamine moiety undergoes a reversible protonation-deprotonation process, which results in intensity changes in the absorption and emission spectra. This derivative exhibits good photostability, good selectivity, high sensitivity, and is employed to exhibit the pH within the rough endoplasmic reticulum of living cells.

A simple, efficient and ecofriendly one pot synthesis protocol has been developed for the synthesis of N-substituted decahydroacridine-1,8-diones by using an efficient and recyclable solid acidic silica supported MoO3/SiO2 catalyst from a condensation of aldehyde, amine and cyclic 1,3-diketone in THF. The reaction using MoO3/SiO2 catalyst was carried out under mild condition with very high yields up to 92%. The present approach of this methodology offers several advantages such as shorter reaction times, good yields, low cost, environmentally benign, milder reaction conditions, easy recovery of catalyst and reusability.

This paper reports the dielectric and photoluminescence measurements of ossiointegrated strontium doped hydroxyapatite bioceramic. The study on invitro bioactivity of Sr-HAp is carried out by using modified simulated body fluid. Dielectric properties of these ossiointegrated samples are studied in the frequency range 10 Hz to 1 MHz at room temperature. Dielectric constant is found to be decreasing with increase in incubation period and frequency of applied ac field. Higher the period of incubation and applied ac frequency, higher is the dielectric loss. AC conductivity shows frequency independent behaviour for all samples in lower frequency region and then increases linearly with increase in frequency. Sample incubated for longer duration shows higher conductivity. The optical properties of incubated Sr-HAp samples are also investigated with photoluminescence (PL) technique. The PL study shows the blue emission at around 476 nm when excited at 409 nm. The PL in tensity increases with increase in incubation duration and Sr-substitution.

The Cover Feature illustrates the outstanding liquid‐crystalline properties of unsymmetrically substituted naphthalenediimides through amide hydrogen bonding and hydrophobic interactions along with p—p stacking. More information can be found in the Full Paper by N. V. Ghule et al. on page 61 in Issue 1, 2018 (DOI: 10.1002/open.201700151).

Construction of thermodynamically stable nanostructures on the nano- to millimeter scales through noncovalent bonding plays an important role in material science. The self-assembly of tetra-alkylamino core-substituted naphthalene diimides (cNDIs) with variable alkyl chains (C8H17, C12H25, and C16H33) added on to the core leads to the formation of a variety of controlled morphologies and well-defined nanostructures. Such structures include nanorods, vesicular, belts, twisted ribbons, and donutlike morphologies (formed in CHCl3/MeOH and CHCl3/hexane mixtures) generated through solvophobic control. UV/Vis absorption and fluorescence spectroscopy demonstrate molecular aggregation in solution. Furthermore, SEM was employed to visualize the supramolecular self-assembled nanostructures. The growth of these structures is mainly due to packing of hydrophobic alkyl chains and π-π stacking of the cNDI core. The present study paves the way to rational and controlled designs of nanostructures made of optically active dyes (naphthalene diimide); this may open a new avenue towards tuning nanodimensional morphology.

A new receptor based on dipyrrolyl-bis-sulfonamide (DPBS) has been described. The colorimetric and long range UV investigation properties of this receptor reveal that it recognised biologically important anions such as F−, H2PO4−, AcO− in chloroform. The sensing capabilities of the receptor DPBS for these anions were determined by means of florescence and 1H-NMR spectroscopy.

The self-assembly of spherical silver nanoparticles with variable size and controlled organization using triglycine as an organic template is described. Triglycine and silver nitrate were used as the starting materials for the preparation of the spherical nanoparticles, and in the presence of copper cations, the particles further self-assembled into one dimensional nanostructures. The formation of supramolecular nanoaggregates was evaluated by means of UV/vis, TEM, SEM, and energy dispersive X-ray spectroscopy.