In this manuscript, the authors reported an Electrochemical Sensor Development for Detecting Organophosphate Pesticide using CuO Nano-grass Electrode. The developed sensor was used organophosphate pesticides (OPPs); namely malathion and chlorpyrifos. The manuscript is well organized. However, some issues in this work need further attention and clarification. I suggest it can be accepted for publication after some careful revision.

1. The literature citation can be enhanced; references can be included to make the manuscript much better (a paragraph must be added about importance of analytical and electroanalytical methods in determination of environmental analysis):

2. The grammar, sentence structure, and clarity of phrasing throughout the manuscript need to be improved.

3. The fabrication procedure of the modified electrode is not clear. Author should explain and enhance the schematic structure of the developed sensor.

4. Authors should explain the electrochemical oxidation mechanism of the detected analyte at the solid/liquid interface.

5. Prior the modification process the work electrode surface must be treated to improve the adhesion of the sensitive layer. Why authors don’t speak about the treatment procedure?

6. Authors should provide more detail about the conditions of storage of the sensor after measurements.

7. The figures are not at standards. The x and y scaling should be appropriate. Rescale the numbers with proper intervals.
8. The quality of the figures is low (Fig 2, 3, 6, 7, 9 and 10).
9. The regeneration of this electrochemical sensor should be explained in this report?
10. All references must be verified and actualised.

The revised version of this paper was organized and structured according to the reviewers comments. As my opinion i recomend this paper for publication in your honorable journal