Introduction: Lateral flow assay method is a test for rapid detection of morphine that h-as many applications in identification of ad-dicts. However, detection level of the sys-tem has limited its application. This rese-arch examined how to improve the detec-tion level and sensitivity of this system.
Materials & Method: pH of conjugation, OD of conjugated material and concentr-ation of morphine-BSA in the test band w-ere effective on the detection level of this system. To determine optimum pH, a com-mercial kit (Gold in a box) was used. By applying various concentrations of morp-hine solution, and considering a constant concentration of morphine-BSA, the opt-imal OD was set. Then, the optimal conc-entration of morphine-BSA was obtained for a fixed amount of OD. Effect of block-ing the conjugated pad and addition of su-gar to the conjugated substance were also studied.
Findings: Optimum values of pH and OD was pH=8.4 and OD=1. Optimum conce-ntration of morphine-BSA in the test band was obtained to be 0.5 mg/ml. Cut-off value of optimized kit attained to 25 ng/ml. After comparing the results with a standard kit, sensitivity and specificity of the optimized kits were 100 % and 99% , respectively.
Discussion & Conclusion: Finding and opt-imizing the effective factors on the perf-ormance of diagnostic lateral flow method can be an effective strategy to increase the sensitivity and reduce the detection level of this system.
shamlo ahmad H, heat M, rashedi H, ovlad G R, latifi A M, haidari moghadam R. Optimization of Effective Parameters on Cut-off of Rapid Detection System of Morphine Based on Lateral Flow Assay (LFA) Method. J. Ilam Uni. Med. Sci. 2014; 22 (3) :19-26 URL: http://sjimu.medilam.ac.ir/article-1-1942-en.html