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New oral anticoagulants (NOAC) are approved for several indications for prophylaxis and treatment of venous thromboembolism and for prevention of embolism in atrial fibrillation at fixed daily doses without need of laboratory guided dose adjustment. Due to their low molecular weight of about 500 to 600 Dalton and their hydrophilicity free anticoagulant is excreted immediately through glomerular filtration into the urine. Impairment of renal function may increase the plasma concentration of the anticoagulants and lowered creatinine clearance is a declared contraindication. In contrast to the initial aim of development the anticoagulant effect is required to be determined in special clinical situations. Several specific and non-specific assays using plasma samples are currently undergoing standardization. As all NOACs are excreted into the urine, specific assays were developed for this matrix to determine them quantitatively of qualitatively. Urine samples can be easily and repetitively obtained avoiding problems and risks associated with blood sampling. The qualitative assay can be performed as a point of care test (POC) also by the patient by judging the different colours for the absence or presence of the drugs with the naked eye. The test is rapid (results available within 15 min), sensitive, specific and accurate and does not require a purified NOAC as control. The tests may be a tool for clinicians who need to know for treatment decisions if a NOAC is on board or not. As the tests are specific for oral direct thrombin inhibitors and for oral direct factor Xa inhibitors, the indication does not interfere with other qualitative POC test in development using clotting systems. The test may be indicated for patients at acute hospitalization, before surgery or central nervous system puncture anaesthesia, if fibrinolytic therapy is indicated, acute deterioration of renal function, and for control of adherence to therapy.

In previous work, the photocatalytic stability during the recycled degradation is employed to evaluate the inhibitory effect of photocorrosion. Then, a significant question arises: is the photocatalytic stability only related to the photocorrosion for ZnO? The answer turns out to be no in our work. The phenomenon of photocatalytic reaction-induced selective corrosion of ZnO nanosheets was firstly revealed. It is found that the special corrosion not only needs UV light irradiation, but also results from the photocatalytic reaction. Then, the impacts of this special corrosion and photocorrosion on morphology and photocatalytic stability were compared. It is found that the PRIS corrosion shows more mass loss, more selective etching and more decrease of unit mass photocatalytic activity than that of photocorrosion. The results indicate that the special corrosion-induced active face loss rather than the photocorrosion-induced mass loss can be fatal for the photocatalytic stability. Accordingly, a direct and visual confirmation of inhibitory effect of loaded Ag against selective corrosion is revealed.