Question: 1.This protocol for urine sample, and our sample will be human serum, so do they have a different protocol for blood sample or it is a same protocol? and if it will be a plasma sample, what is the best anticoagulant will be added? 2. They do not show the stability of sample before protocol that will be done (storing) either in 4,-20 or -80 C. 3. They do not show a reference range, so if they have? we need to know it and that for deciding to add healthy control in our study or not? 4.What is their diluent reagent? saline? Answer: 1.according to the requirements of the specimen use EDTA or sodium citrate as anticoagulant. 2.1-3 days testing samples can be stored at 4℃standby. If special reasons need to periodically collect samples, please put the samples separately and placed in -20℃or 70℃condition, avoid repeated freezing and thawing. 3. The Elisa kit is marked with the detection range 4. diluent reagent is PBS