A 2-D π–π dimer model system to investigate structure-charge transfer relationships in rubrene

© The Royal Society of Chemistry 2019Rubrene (5,6,11,12-tetraphenyltetracene) is undoubtedly one of the best performing organic charge transfer mediating materials, with experimentally determined mobilities up to 40 cm2 V−1 s−1. Consequently, there has been increasing interest by means of crystal engineering in trying to generate rubrene-based materials with analogous or even superior conducting properties. Often, experimental measurements are carried out in thin film architectures of these materials, where measured properties can be detrimentally impacted by device manufacture rather than intrinsic charge transfer properties of the material. The latter results in discarding potential good performers. To address these concerns, we report a two-dimensional model system that will allow researchers to predict charge transfer properties of their materials solely requiring the coordinates of the π–π stacking motifs. We envisaged this study to be of significant interest to the increasingly large community of materials scientists devoted to the realisation of improved organic charge mediating materials and particularly to those engaged in exploiting rubrene-based architectures.Peer reviewedFinal Accepted Versio

Effects of tooth-brushing force with a desensitising dentifrice on dentine tubule patency and surface roughness

Objectives To investigate the effects of a 5% NovaMin containing dentifrice on dentine tubule patency and surface roughness at 100 g and 400 g tooth brush abrasion forces. Methods 75 polished human dentine samples were prepared and randomly allocated into one of five groups; control (1), Na2PFO3 100 g abrasion force (2), NovaMin 100 g (3), Na2PFO3 400 g (4) and NovaMin 400 g (5). The control group underwent two 2-minute cycles of artificial saliva (AS), one 2-minute erosion cycle; the rest underwent two toothbrush abrasion cycles in an AS/dentifrice slurry and one 2-minute erosion cycle. All samples were imaged at baseline and post intervention using Tandem Scanning Microscopy and Profilometry to analyse tubule patency and roughness. Results Mean tubule patency increased significantly between baseline and post intervention in groups 1,2 and 4 and decreased significantly post intervention in groups 3 and 5 (p < 0.01). Post intervention, there were statistically significant differences in mean patent tubules between NovaMin and the Na2PFO3 and control groups (p < 0.001). Surface roughness increased for all groups between baseline and post interventions (P < 0.001); mean (SD) roughness increases for groups 1, 2, 3, 4 and 5 were 0.14 (0.05) μm, 0.18 (0.04) μm, 0.16 (0.06) μm, 0.19 (0.07) μm and 0.21 (0.02) μm respectively. Differences between group 1 and 5 were significant (p < 0.01). Conclusions Brushing with NovaMin resulted in significant dentine tubule occlusion at 100 g and 400 g, but brushing with Na2PFO3 resulted in increased tubule patency. Surface roughness increased significantly at 400 g brushing with NovaMin. There was no correlation between tubule patency and surface roughness. Clinical significance A NovaMin desensitising dentifrice resulted in tubule occlusion even at high brushing forces. There was minimal increase in surface roughness at the lower (100 g) brushing force

Sustainable polyurethane coatings derived from alkyds of Camelina oil monoglycerides

This study presents the synthesis of sustainable urethane coatings derived from alkyds of Camelina oil (CO) monoglycerides, offering a sustainable alternative to petrochemical resources. Utilizing immobilized lipase for a low-temperature glycerolysis reaction, high-yield monoglycerides were obtained from CO. These were then reacted with dibasic acids (phthalic, succinic, and maleic anhydride) to produce alkyd diols, confirmed by both nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. The hydroxyl functionality of the alkyd diols showed a significant enhancement (up to 2200%) over crude CO produced Camelina-based alkyd diols were incorporated into polyurethane formulations and applied to metal substrates. Comprehensive performance evaluations revealed their superior mechanical, thermal, and chemical properties in comparison with previously reported plant-based alkyd-urethane coatings, especially for the phthalic anhydride-derived alkyd diol. The present research underscores the potential of Camelina-derived alkyds in creating high-performance, plant-based coatings, aligning with recent sustainability trends in material science.ye

New FTY720-docetaxel nanoparticle therapy overcomes FTY720-induced lymphopenia and inhibits metastatic breast tumour growth

Purpose: Combining molecular therapies with chemotherapy may offer an improved clinical outcome for chemoresistant tumours. Sphingosine-1-phosphate (S1P) receptor antagonist and sphingosine kinase 1 (SK1) inhibitor FTY720 (FTY) has promising anticancer properties, however, it causes systemic lymphopenia which impairs its use in cancer patients. In this study, we developed a nanoparticle (NP) combining docetaxel (DTX) and FTY for enhanced anticancer effect, targeted tumour delivery and reduced systemic toxicity. Methods: Docetaxel, FTY and glucosamine were covalently conjugated to poly(lactic-co-glycolic acid) (PLGA). NPs were characterised by dynamic light scattering and electron microscopy. The cellular uptake, cytotoxicity and in vivo antitumor efficacy of CNPs were evaluated. Results: We show for the first time that in triple negative breast cancer cells FTY provides chemosensitisation to DTX, allowing a four-fold reduction in the effective dose. We have encapsulated both drugs in PLGA complex NPs (CNPs), with narrow size distribution of ~ 100 nm and excellent cancer cell uptake providing sequential, sustained release of FTY and DTX. In triple negative breast cancer cells and mouse breast cancer models, CNPs had similar efficacy to systemic free therapies, but allowed an effective drug dose reduction. Application of CNPs has significantly reversed chemotherapy side effects such as weight loss, liver toxicity and, most notably, lymphopenia. Conclusions: We show for the first time the DTX chemosensitising effects of FTY in triple negative breast cancer. We further demonstrate that encapsulation of free drugs in CNPs can improve targeting, provide low off-target toxicity and most importantly reduce FTY-induced lymphopenia, offering potential therapeutic use of FTY in clinical cancer treatment

4-(4-Chloro­phen­yl)-6-hydr­oxy-5-(2-thienyl­carbonyl)-6-(trifluoro­meth­yl)-3,4,5,6-tetra­hydro­pyrimidin-2(1H)-one monohydrate

The asymmetric unit of the title compound, C16H12ClF3N2O3S·H2O, contains two crystallographically independent organic mol­ecules and two water mol­ecules. The organic species are linked by an inter­molecular O—H⋯O hydrogen bond, while the water mol­ecules are connected to them through inter­molecular O—H⋯N hydrogen bonds. The thio­phene and phenyl rings are oriented at dihedral angles of 62.35 (4) in the first independent mol­ecule and 60.74 (5)° in the second, while the pyrimidine rings adopt twisted conformations in both molecules. Intra­molecular N—H⋯F inter­actions result in the formation of two five-membered rings having envelope conformations. In the crystal structure, further inter­molecular O—H⋯O and N—H⋯O hydrogen bonds link the mol­ecules into chains

A study of diabetic retinopathy in diabetic foot syndrome in Western Regional Institute of India

Background: Diabetes is a rapidly growing health challenge and potential epidemic across low-and-middle-income countries like India. Diabetic retinopathy (DR) is a consequence of diabetic microangiopathy, which may cause visual deterioration due to macular edema in any stage and vitreous hemorrhage or tractional retinal detachment in the advanced proliferative retinopathy stages. Aims and Objectives: The aim was to study the retinopathy status in diabetic patients with a risk of diabetic foot syndrome (DFS) visiting a western regional hospital in India. Materials and Methods: In this cross-sectional study, all patients with diabetes mellitus (DM) with a risk of DFS, visiting a tertiary care hospital during the study period, underwent an ophthalmological evaluation for documentation of their retinopathy status. Results: One hundred and fourteen patients diagnosed to have a risk profile for DFS were included in the study. Their mean age was 61.22 years and 81.6% were males. The mean duration of DM was 12.24 years, respectively. Of the 114 patients, 72 had DR. An increased presence of retinopathy in patients with an increased risk grade of diabetic foot (DF) was found significant by the Chi‐square test. (P<0.001). Conclusion: Our study found an increased presence of DR in Western Indian cohort with DFS. The severity of retinopathy was greater in patients with higher grades of risk for DF, therefore establishment of an association between DR and DFS will help in developing an integrated management strategy for these two grave consequences of diabetes