Portable liquid chromatography for point-of-care testing of glycated haemoglobin

Liquid chromatography (LC) coupled with absorption detection plays an important role in the analytical field. However, the miniaturisation of the whole system is still a challenging problem. Here we developed a compact and lightweight LC system with overall size of 20 cm × 16 cm × 16 cm and weight of 1.8 kg for the fast and accurate measurement of glycated haemoglobin (HbA_1c). The system mainly comprises a battery-operated electrolysis micropump (EMP), a highly integrated LC microchip and an LED-based absorbance detector. The good linearity (R² = 0.9860) and low limit of detection (LOD) (about nine times lower than the commercial detector) of the LED detector were measured to meet the requirement of the on-chip determination. The inaccuracy (≤ 4.3 %) and repeatability (≤ 2.8 %) of the LC system were successfully verified by measuring the HbA_1c levels of patients with diabetes and comparing the results with those from a commercial LC instrument. Thus, the developed LC system showed great potential for accurate and point-of-care diabetes diagnostics.