Please look at the following below links which may help you in your analysis:

http://www.cysonline.org/article.asp?issn=2229-5186;year=2011;volume=2;issue=1;spage=21;epage=25;aulast=Shrivastava

https://www.eflm.eu/files/efcc/Zagreb-Theodorsson_2.pdf

https://pubs.acs.org/doi/pdf/10.1021/ac0302859

https://dnr.wi.gov/regulations/labcert/documents/guidance/-LODguide.pdf

Thanks

Hello M. Mahafuzur Rahman ,

As far as I am concerned, when I work on immunosensors I take the lowest quantity of analyte that can be reliably detected (usually 3 times the noise).

Best regards,

Marie B.

The most important point is that in a publication or other document, you should describe in enough detail, how you calculated it. There is not only one way to estimate a limit of detection. If you want to compare limits of detection, you have to use the same calculation method for all.