Development Of A New Type Of Piezoelectric Immunosensor Array And It's Application In Clinical Immunophenotyping Of Acute Leukemias

Leukemia is a type of hematologic malignant tumor of high heterogeneity and heterology. Diagnosis of leukemia is mainly based on MICM typing, and immunophenotyping is an important adjunctive method of phenotype recognition and diagnosis of leukemia, which has substantial significance to exactly choose clinic treatment schema, judge prognosis correctly and analyze characters of different subtype of leukemias.The main immunological methods for detecting the expression of differentiated antigens of leukocytes include immuno-histochemistry (IH), flow cytometry (FCM), fluoroimmunoassay, these methods used to date are, however, of either time consuming, or complicated entailing expensive instrumentation and inefficiency of quantitation. Therefore, an integrated piezoelectric immunosensor array has been initiated to immunophenotype acute leukemias in clinic in our experiment.Each of the quartz crystal microbalance (QCM) was fabricated with plasma-polymerized film (PPF) of n-butylamine and nanogold particles to be used to immobilize antibodies in oriention. Leukocytic lineage-associated monoclonal antibodies were separately immobilized onto the nanogold modified surface of the crystals, which were constructed by 2×2 type of probes forming a QCM-based immunosensor array. The main parameters were optimized, including the immobilization amount of antibodies, pH, immunoreaction time, sample dilution ratio, etc.It was found that the developed technique could readily identify the expressed degree of leukocytic lineage-associated antigens in a short time, and might monitor dynamically the immunoreaction processes. Moreover, comparison studies were carried out for CD antigens expressed on the nucleated cells isolated from 96 acute leukemic patients and 24 normal subjects using the QCM-based immunosensor method and the fluoroimmunoassay. Results obtained by immunophenotyping patients samples with the immunosensor-based method has no significant difference to fluoroimmunoassay.This new immunosensor array showed some advantages of high sensitivity, high specificity, good reproducibility, easy operation, and low cost over other methods. The results of specimen evaluation indicated that it might be clinically suitable for quantifying human differentiated leukocytes and immunophenotyping of acute leukemias.