Rapid detection of glycosylated hemoglobin levels by a microchip liquid chromatography system in gradient elution mode

• Published in: Analytica chimica acta 2024-02, Vol.1288, p.342186-342186, Article 342186
• Main Authors: Jiao, Dezhao, Zhang, Ruirong, Zhang, Hantian, Ma, Haoquan, Zhang, Xiaorui, Fan, Xiaoguang, Chang, Honglong
• Format: Article
• Language: English
• Subjects: Glycosylated hemoglobin; Gradient elution; Liquid chromatography; Microchip; Microfluidic chip
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2023.342186

The determination of glycosylated hemoglobin (HbA1c) is crucial for diabetes diagnosis and can provide more substantial results than the simple measurement of glycemia. While there is a lack of simple methods for the determination of HbA1c using a point-of-care test (POCT) compared to glycemia measurement. In particular, high-performance liquid chromatography (HPLC) is considered the current gold standard for determining HbA1c levels. However, commercial HPLC systems usually have some sort of disadvantages such as bulky size, high-cost and need for qualified operators. Therefore, there is an urgent demand to develop a portable, and fast HbA1c detection system consuming fewer reagents. We present a novel microchip that integrates a micromixer, passive injector, packed column and detection cell. The integrated microchip, in which all the microstructures were formed in the CNC machining center through micro-milling, is small in size (30 mm × 70 mm × 10 mm), and can withstand 1600 psi of liquid pressure. The integrated design is beneficial to reduce the band broadening caused by dead volume. Based on the microchip, a microchip liquid chromatography (LC) system was built and applied to the analysis of HbA1c. The separation conditions of HbA1c in blood calibrator samples were optimized using the microchip LC system. Samples containing four levels of HbA1c were completely separated within 2 min in optimal gradient conditions, with an inaccuracy (