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Highlights • We report a portable absorption photometry-based microfluidic system for detection of human triglyceride, albumin and total protein. • A new pump-free microfluidic chip is developed and contributed to detection sensitivity and miniaturization. • Quantitative analysis of three blood test items in the required concentration range is robust and reproducible. Abstract We reported a novel integrated portable human blood system based on absorption photometry and microfluidic technology. A capillary pump for fluid control was embedded in microfluidic chip instead of heavy syringe pump. The analytes could automatically flow, mix and react in chip. It achieves long-term stability of hydrophilic microfluidic channel surface for rapid and sensitive detection. Herein, we detected three analytes from human blood, including triglyceride (TGL), albumin (ALB) and total protein (TP) which are very important for health examination. All components of this system including light-emitting diode (LED) light source, microfluidic chip, photodiode detector (PD), electronic circuit, Organic LED screen and memory card were fully integrated into a portable instrument with small size (11.2 × 7.2 × 6.1 cm). The pair of LED and PD was used for measuring light absorbance of biochemical assay. The limit of detections (LODs) for TGL, ALB and TP were estimated to be below 0.1 mmol/L, 4 g/L and 10 g/L respectively, which is significantly below the clinical cut-off value. Passing − Boblok regression analyses were used to achieve the evaluation for this system. It showed good accuracy and feasibility of our system and was expected to be useful as a potential clinical tool for human blood serum test. [ABSTRACT FROM AUTHOR]

We report the application of a fully automated surface-enhanced Raman scattering (SERS)-based solenoid-embedded microfluidic device to the quantitative and sensitive detection of anthrax biomarker poly-γ- d -glutamic acid (PGA) in solution. Analysis is based on the competitive reaction between PGA and PGA-conjugated gold nanoparticles with anti-PGA-immobilized magnetic beads within a microfluidic environment. Magnetic immunocomplexes are trapped by yoke-type solenoids embedded within the device, and their SERS signals were directly measured and analyzed. To improve the acccuracy of measurement process, external standard values for PGA-free serum were also measured through use of a control channel. This additional measurement greatly improves the reliability of the assay by minimizing the influence of extraneous experimental variables. The limit of detection (LOD) of PGA in serum, determined by our SERS-based microfluidic sensor, is estimated to be 100 pg/mL. We believe that the defined method represents a valuable analytical tool for the detection of anthrax-related aqueous samples. [ABSTRACT FROM AUTHOR]