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Organic materials are receiving more attention in the solar cell due to their better solution process, controllable synthesis, tunable chemical and physical properties. However, the focus problem of compatibility and aggregation is to be solved urgently in organic materials, which inevitably limits them widely application. To this end, an inorganic–organic hybrid materials with wide-band absorption is designed and prepared, that incorporates octavinyl-polyhedral oligomeric silsesquioxane with 6-bromoquanaldine to produce H1, then reacts with squaric acid to design H2, which efficiently avoids the fluorescence quenching due to the steric hindrance. The electrochemical results shows that the energy level of H2 is match well with the commercial dye N719. Hence it shows a better photovoltaic performance based on dye-sensitized solar cell, along with power conversion efficiency up to 7.73% when it is co-sensitized with N719. The hybrid system exhibits good performances in solar cell and long-term stability.

Combining octavinyl-polyhedral oligomeric silsesquioxane (OV-POSS) with amine-containing polyacrylamide (OV-POSS co-poly(acrylamide)) gives a new fluorescent polymeric chemo-sensor with complete water solubility. It shows better selectivity for Fe3+ in water over a wide detection range (pH = 4–10). The incorporation of Fe3+ into OV-POSS co-poly(acrylamide) results in a significant fluorescence enhancement in water over other metal ions. The bound ratio of OV-POSS co-poly(acrylamide)–Fe3+ complex was determined to be 1 : 2 according to the Job's plot. The association constant (Ka) of Fe3+ binding with the chemosensor was 7.416 × 107, and the detection limit was 0.9 × 10−9 M. Moreover, it was found that the system possessed low cytotoxicity, good permeability, high stability, and compatibility. Hence, it can be successfully applied in bio-imaging with bright blue fluorescence. In addition, a visible color change to the naked eye from colorless to bright yellow could be directly observed when Fe3+ was added into the chemosensor OV-POSS co-poly(acrylamide) compared with other metal ions.

Combining octavinyl-polyhedral oligomeric silsesquioxane (OV-POSS) with amine-containing polyacrylamide (OV-POSS co-poly(acrylamide)) gives a new fluorescent polymeric chemo-sensor with complete water solubility. It shows better selectivity for Fe3+ in water over a wide detection range (pH = 4-10). The incorporation of Fe3+ into OV-POSS co-poly(acrylamide) results in a significant fluorescence enhancement in water over other metal ions. The bound ratio of OV-POSS co-poly(acrylamide)-Fe3+ complex was determined to be 1 : 2 according to the Job's plot. The association constant (Ka) of Fe3+ binding with the chemosensor was 7.416 × 107, and the detection limit was 0.9 × 10-9 M. Moreover, it was found that the system possessed low cytotoxicity, good permeability, high stability, and compatibility. Hence, it can be successfully applied in bio-imaging with bright blue fluorescence. In addition, a visible color change to the naked eye from colorless to bright yellow could be directly observed when Fe3+ was added into the chemosensor OV-POSS co-poly(acrylamide) compared with other metal ions.

Objectives To develop and validate a new technique for hand hygiene for use in healthcare settings; to evaluate correlation between bioluminescence and conventional time consuming viable counting methods; to use bioluminescent constructs of bacterial pathogens as a real time biosensors for rapid bactericidal monitoring and to conduct in vitro toxicity tests of the Himalayan oregano oil (HOO) against human cell lines. The ultimate aim of this study is to improve the quality of care of patients through application of a new hand hygiene which could be more acceptable to users while maintaining the efficacy of current hand hygiene disinfectant. Methods: Representatives of the common UK bacterial pathogens Escherichia coli, Pseudomonas aeruginosa and Methicillin sensitive Staphylococcus aureus were used in experiments. Strains used had been previously genetically modified with addition of lux CDABE operon to express bioluminescence in order that they could be used as reporter of viable metabolically active cells to show a real time in situ antimicrobial effect of HOO. Oregano oil samples were analysed for the percentage contents of thymol and carvacrol using gas chromatography. Potential toxicity of Oregano oil at a range of concentrations on cultured human keratinocytes and Jurkat cells were determined using Neutral Red, WST and MTS assays. Results: High correlation was obtained between viable count and bioluminescence. Application of HOO in concentrations effective against bacteria was found to be safe to human keratinocytes (fig.1 and 2) Conclusions: Bioluminescence has the capability to replace the plate culture method for evaluating the efficacy of a new antimicrobial product as it provides a rapid means of collecting data on the antimicrobial action of HOO. HOO may have the potential as a natural potent antimicrobial agent in the health care setting, as it has demonstrated biocidal action towards significant pathogens in a short time. Application of the oil in the correct dilution was found to be safe on human keratinocytes.

Die vorliegende Studie wurde in einer Gruppe von Dörfern im Ostsudan, Gedaref State, durchgeführt. Bei 100 Patienten mit der Verdachtsdiagnose Kala Azar- oder Post-Kala Azar- Leishmaniose war der Erregernachweis mit der PCR direkt in klinischen Proben, die auf Filterpapier aufgebracht worden waren, ohne vorherige Kultivierung erfolgreich. In dieser PCR wurden die ribosomalen, internal transcribed spacer (ITS1 & ITS2) amplifiziert, weil sie sehr variabel sind, eine klare Speziesidentifizierung gestatten und bei weiterführenden Analysen der PCR-Produkte auch der Nachweis stammspezifischer Unterschiede erwartet werden konnte. Für die Analyse der Diversität von Leishmania donovani-Isolaten aus dem Sudan wurden 4 verschiedene PCR-basierte Methoden eingesetzt: das PCR-Fingerprinting mit unspezifischen Einzelprimern, die RFLP- Analyse des amplifizierten ITS-Locus, ,,single strand conformation polymorphism (SSCP)- Analysen der amplifizierten ITS-Region, des Gens, welches für die Hauptoberflächenprotease (gp63) kodiert, und anonymer DNA- Fragmente sowie Sequenzanalysen der entsprechenden Zielregionen. Das PCR-Fingerprinting und die Restriktionsanalyse der ITS-Region lieferten weitgehend übereinstimmende Fragmentmuster für alle untersuchten L.donovani-Stämme. 12 unterschiedliche Profile wurden bei der SSCP-Analyse des ITS1-Locus für 86 Isolate aus dem Sudan erhalten, während der ITS2-Locus bei diesen Stämmen hochkonserviert war und nur ein Stamm ein unterschiedliches SSCP-Muster aufwies. L. Donovani -Stämme anderer geographischer Herkunft hatten unterschiedliche ITS2-Profile in der SSCP. Für den gp63 - Locus waren 3 polymorphe SSCP-Muster bei 31 untersuchten sudanesischen Isolaten nachweisbar. Für die meisten der anonymen DNA-Fragmente, L510, L413, LK413, L0308 UND L0114, konnten leider nur von 8 kultivierten Stämmen gute PCR-Produkte erhalten werden. Lediglich das Fragment L0110 konnte erfolgreich von 31 auf Filterpapier aufgebrachten Proben direkt amplifiziert werden. Die Suche nach Polymorphismen mit der SSCP ergab keine Unterschiede in diesen anonymen DNA-Regionen, mit Ausnahme des Fragments L0114, das zwei verschiedene Muster aufwies. Die Ergebnisse der SSCP-Analysen und der DNA- Sequenzierung stimmten gut überein, wodurch bestätigt wurde, dass die SSCP genetische Unterschiede auf dem Niveau einzelner Basenaustausche nachweisen kann. Die SSCP- Technik hat Vorteile gegenüber den anderen Methoden, die für die Untersuchung von Sequenzvariationen innerhalb der Spezies L. donovani angewandt wurden. Es konnten keine Korrelationen zwischen der Form der klinischen Manifestation und den Ergebnissen des PCR- Fingerprinting, der ITS-RFLP- und ITS-SSCP- Analysen festgestellt warden. Diese Studie ist von besonderem Nutzen in epidemiologischen Feldstudien, bei denen die Kultivierung der Erreger besonders in Entwicklungsländern extrem schwierig sein kann., This study was carried out in clusters of villages that represent an endemic focus of visceral leishmaniasis (VL). These villages were located in Gedaref state, eastern Sudan. For diagnostic purposes polymerase chain reaction (PCR) was performed successfully, directly from clinical samples spotted on filter papers with no prior cultivation from 100 patients suspected of having kala-azar or post kala-azar dermal leishmaniasis. Mainly the ribosomal internal transcribed spacer (ITS1 & ITS2) were targeted in PCR because this region is more variable and allows clear species identification and also strain differences could be expected by further analysis of these PCR products. PCR was found to be more sensitive compared to the gold standard microscopic method. Four PCR based approaches were used to analyse diversity within Sudanese isolates of Leishmania donovani. Methods compared were fingerprinting with single non-specific primers, restriction analysis of the amplified ITS locus (RFLP), single-stranded conformation polymorphism (SSCP) of the ITS region, major surface protease (gp63) gene, anonymous DNA fragments and sequencing of these targeted regions. When PCR fingerprinting and restriction analysis of ITS region were applied, highly similar fragment patterns were observed for all strains of L. donovani studied. The ITS1 locus gave 12 different SSCP profiles among the 86 Sudanese isolates, where as the ITS2 locus was highly conserved among the 86 samples with the exception of 1 isolate. Strains of L. donovani derived from other geographical areas were found to have different ITS2 patterns. The gp63 locus gave 3 polymorphic patterns among 31 Sudanese isolates. Concerning most of the anonymous DNA fragments namely, L510, L413, LK413, L0308 and L0114 unfortunately, we succeeded to get good PCR products only from DNA extracted 8 successful cultures. Only for the fragment L0110 we were able to get good PCR products from 31 samples spotted on filter papers. When these PCR products were investigated for polymorphisms using SSCP no differences were observed with exception of L0114 region, which showed 2 patterns. SSCP analysis correlates well with results of DNA sequencing and confirmed that SSCP was able to detect genetic diversity at the level of a single nucleotide. SSCP had advantages over the other methods employed for investigating of sequence variation within the species L. donovani. There was no correlation between the form of clinical manifestation of the disease and the PCR fingerprinting, ITS-RFLP, or ITS-SSCP characteristics. This study is beneficial particularly in epidemiological studies based on field-work where obtaining cultures can be extremely difficult especially in developing countries.