Co/Co‐N nanoparticles incorporated nitrogen‐doped nanoporous carbon (Co/Co‐N@NPC) nanostructures were fabricated via pyrolysis of metal organic framework, ZIF‐67, under argon atmosphere. The ZIF‐67 derived Co/Co‐N@NPC modified carbon paste electrode exhibited excellent performance during electroanalysis of dopamine, displaying two linear ranges; 10 nM to 50 μM, and 50 μM–500 μM with sensitivity of 12.4±0.3 μA/μM/cm2 and11.69±0.06 μA/μM/cm2, respectively. The modified electrodes were observed to be highly selective towards dopamine even in presence of other interfering biomolecules such as ascorbic acid, glucose and uric acid. To the best of our knowledge, the sensing ability of Co/Co‐N@NPC with a lower limit of detection as 6 nM is the best compared to the previously reported cobalt mediated sensors for dopamine. Practical feasibility of the sensor was demonstrated in real sample analysis of dopamine measurement in human urine samples and dopamine hydrochloride injection samples.

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The remedial investigation/feasibility studies conducted at certain Army installations showed a need to clean up contaminated sites, where high levels of ammunition chemicals such as 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitrobenzene (TNB), 1,3-dinitrobenzene (DNB), and their degradation products/metabolites were detected in surface soil and groundwater. TNB is a photodegradation product of TNT; it is not easily degraded, and persists in the environment. The toxicity data on TNB are scanty. Hence the U.S. Environmental Protection Agency in 1988 (US. EPA, 1997) developed a reference dose (RfD) for TNB (0.00005 mg/kg/d for chronic toxicity) based on the toxicity of DNB, which is structurally similar to TNB. Since then we have completed acute, subacute, subchronic, chronic, reproductive, and developmental toxicity studies and toxicokinetics studies. We have reviewed the mammalian toxicity data for TNB and have determined the no observed adverse effect levels (NOAEL) and low observed adverse effect levels (LOAEL) for subchronic, chronic, reproductive, and developmental toxicity. Based on the newly determined NOAEL and LOAEL values, we have now developed a new RfD for TNB (0.03 mg/kg/d), based on the chronic toxic effects on hematology and histopatho logical changes in testes and kidney.

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