Herein,
a Au-Au/IrO2 nanocomposite with tandem enzyme-mimicking
activity was innovatively synthesized, which can show outstanding
glucose oxidase (GOx)-like activity and peroxidase-like activity simultaneously
under neutral conditions. Moreover, a Au-Au/IrO2@Cu(PABA)
reactor was prepared via encapsulation of the Au-Au/IrO2 nanocomposite in a Cu(PABA) metal organic framework. The reactor
not only exhibits excellent organic solvent stability, acid resistance,
and reusability but also displays better cascade reaction catalytic
efficiency (kcat
/Km
= 148.86 min–1 mM–1) than the natural free enzyme system (GOx/HRP) (kcat
/Km
= 98.20 min–1 mM–1) and Au-Au/IrO2 nanocomposite
(kcat
/Km
=
135.24 min–1 mM–1). In addition,
it is found that the reactor can catalyze glucose or dissolved oxygen
to produce active oxygen species (ROS) including HO, 1O2, and O2
–
· through
its enzyme-mimicking activity. Finally, the novel reactor was successfully
used in organic dye degradation and antibacterial application. The
results show that it can effectively degrade methyl orange, methylene
blue, and rhodamine B, which all can reach a degradation rate of nearly
100% after interacting with Au-Au/IrO2@Cu (PABA) for 3.5
h. Furthermore, the reactor also exhibits excellent antibacterial
activity, so as to achieve a complete bactericidal effect to Staphylococcus aureus and Escherichia
coli at a concentration of 12.5 μg mL–1.
BACKGROUND: The use of safe and effective insecticides against mosquito-borne stocks is still one of the most effective ways to rapidly interrupt the spread of diseases such as malaria, dengue etc., but many insects are resistant to most insecticides and most of the traditional pyrethroids (like permethrin, deltamethrin etc.) contain phenoxy groups so it is easy to form dibenzofuran, a pollutant, after photodegradation. It is therefore necessary to synthesize novel pyrethroids which have better mosquito-killing activity, poor resistance to mosquitoes, and no dibenzofuran formation during photodegradation.
RESULTS: A series of novel dihaloacetylated heterocyclic pyrethroids were synthesized to enhance antimosquito activity. Bioassays based on the guidelines of the Chinese Center for Disease Control and Prevention (CDC) indicate that the synthesized compounds DCA-O (LC 50 = 2.95 ± 0.05 g L −1 ), DCA-01 (LC 50 = 5.83 ± 0.36 g L −1 ) and DCA-11 (LC 50 = 5.79 ± 1.51 g L −1 ) exhibit high insecticidal activities and sensitivity against Aedes albopictus while deltamethrin and permethrin produced moderate levels of resistance. Moreover, the analysis of the photodegradation implies that the novel compounds synthesized by substituting a phenoxy group with a heterocyclic ring do not form dibenzofuran, a pollutant. Lastly, the cytotoxicity data of pyrethroids on human dopaminergic neuroblastoma SH-SY5Y cells confirm that the synthesized compounds have low toxicity for the cells. CONCLUSION: Novel dihaloacetylated heterocyclic pyrethroids, made by simple synthesis steps, have better antimosquito activity, lower drug resistance, are less polluting to the environment and show low toxicity to human nerve cells. This also provides an effective idea for the synthesis of pyrethroids. Novel dihaloacetylated heterocyclic pyrethroids have better antimosquito activity, lower drug resistance, are less polluting to the environment, ahow low toxicity to human nerve cells and simple synthesis steps.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.