Sensitive fluorescence detection of glyphosate and glufosinate ammonium pesticides by purine-hydrazone-Cu2+ complex.

Organophosphorus pesticides play an important role as broad-spectrum inactivating herbicides in agriculture. Developing a method for rapid and efficient organophosphorus pesticides detection is still urgent due to the increasing concern on food safety. An organo-probe (ZDA), synthesized by purine hydrazone derivative and 2,2'-dipyridylamine derivative, was applied in sensitive recognition of Cu2+ with detection limit of 300 nM. Mechanism study via density functional theory (DFT) and job's plot experiment revealed that ZDA and Cu2+ ions form a 1:2 complex quenching the fluorescence emission. Moreover, this fluorescent complex ZDA-Cu2+ was applicable for detecting glyphosate and glufosinate ammonium following fluorescence enhancement mechanism, with detection limits of 11.26 nM and 11.5 nM, respectively. Meanwhile, ZDA-Cu2+ was effective and sensitive when it is used for pesticide detection, reaching the maximum value and stabilizing in 1 min. Finally, the ZDA-Cu2+ probe could also be tolerated in cell assay environment, implying potential bio-application.

Presentations of Meckel's diverticulum at Khyber Teaching Hospital Peshawar.

BACKGROUND: This study was conducted with an objective to observe various presentations of Meckel's Diverticulum in our setting and compare it with other national and international studies. METHODS: It was a retrospective analysis of hospital record carried out at the department of paediatric surgery Khyber Teaching Hospital, Peshawar. A total of 63 patients meeting the inclusion criteria were included in the study who had presented to our unit with signs and symptoms of Meckel's Diverticulum and who were diagnosed either by investigations or at surgery. All the patients were explored and resection and anastomosis performed. We did not do H. Pylori culture. Patients with bleeding per rectum were investigated by Meckel's scan. Analysis of the results was done by SPSS version 10. RESULTS: Majority of our patients presented with obstruction (82.5%) in contrast to the Western studies (around 40%) while only 4.7% presented with bleeding per rectum again in contrast to the Western countries (38.56%). CONCLUSION: There appears to be a geographical and/or racial difference in the presentation of Meckel's diverticulum.