Development of a fluorescence immunochromatographic assay for the detection of zeta globin in the blood of (−−SEA) α-thalassemia carriers

Southeast Asian deletion (−−SEA) α-thalassemia is an inherited monogenic disorder of human hemoglobin, and embryonic globin ζ (hemoglobin ζ, zeta globin chain or Hb zeta chain) has been shown to be a marker that can be used for the identification of carriers of the (−−SEA) α-thalassemia deletion. In this work, a fluorescence immunochromatographic assay (FL-ICA) was established to detect the zeta globin chain in the hemolysates of carriers of the (−−SEA) α-thalassemia deletion. This assay can be completed within 10 min using a simple UV detector and does not suffer from interference from the red background color of the hemolysate. A total of 314 blood samples were tested by FL-ICA and ELISA. The results of these assays were confirmed by PCR, the standard technique for genetic disease testing. The sensitivity and specificity of this novel FL-ICA were 100% and 98.0%, respectively; the corresponding values for the ELISA performed simultaneously were 100% and 99.2%, respectively. In conclusion, a new FL-ICA–a simple, fast, convenient, low-cost method–was developed that may be useful in both high-throughput screening and individual detection of the (−−SEA) α-thalassemia deletion in carriers. Additionally, this qualitative FL-ICA may enlighten the development of a new systems for analysis of other target molecules using whole-blood samples.