title: An integrated microfluidic system for measurement of glycated hemoglobin levels by using an aptamer-antibody assay on magnetic beads.
abstract: Blood glycated hemoglobin (HbA1c), reflecting the average blood glucose level in the proceeding 2-3 months, is recommended for screening/diagnosing and patient management of diabetes. However, accurate measurement of the HbA1c level at the point of care is hampered by costly, large-scale instruments (such as high-performance liquid chromatography) or reagent instability of classical immunologic methods, which involve antibody-based immunoturbidimetry. In this work, an integrated microfluidic system using aptamer-based testing to measure HbA1c in blood samples is therefore presented. This measuring system used nucleic-acid aptamers that exhibited high sensitivity and high specificity for hemoglobin and HbA1c to perform a stable and robust testing. The compact microfluidic system consumed less samples and reagents and significantly shortened the detection time. Combining the advantages of microfluidics and aptamers, this integrated microsystem presents a promising tool for accurate and point-of-case HbA1c detection. To demonstrate its clinical utility, whole blood samples with clinically-relevant concentrations of HbA1c and Hb were automatically measured on the integrated microfluidic system. Experimental data showed that the developed aptamer-based microfluidic system is capable of detecting HbA1c and Hb with a good linear response. The entire process was completed within 25 min. The aptamer-antibody on-chip sandwich immunoassay may be further refined to allow diabetes screening and diagnosis at lower cost and earlier phase to minimize the risk of diabetic complications.
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Ko-Wei
authors.initials: KW
authors.lastname: Chang
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan.
authors.forename: Jinglun
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Ching-Hsuan
authors.initials: CH
authors.lastname: Yang
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan, Taiwan. Electronic address: hsieh@mail.ncku.edu.tw.
authors.forename: Shu-Chu
authors.initials: SC
authors.lastname: Shiesh
authors.affiliation: Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan; Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu, Taiwan; Institute of NanoEngineering and Microsystems, National Tsing Hua University, Hsinchu, Taiwan. Electronic address: gwobin@pme.nthu.edu.tw.
authors.forename: Gwo-Bin
authors.initials: GB
authors.lastname: Lee
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004867:Equipment Design; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation; D018189:Immunomagnetic Separation / Q000295:instrumentation; D060328:Magnetic Phenomena; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D012680:Sensitivity and Specificity
chemical_list: D055910:Antibodies, Immobilized; D052157:Aptamers, Nucleotide; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: Aptamer; Diabetes mellitus; HbA1c; MEMS; Microfluidic