title: A siphonage flow and thread-based low-cost platform enables quantitative and sensitive assays.
abstract: For pump-free, material abundant, portable, and easy-to-operate low-cost microfluidics, a siphonage flow microfluidic thread-based analytical device (S-μTAD) platform enabling quantitative and sensitive assays was designed. Renewable and continuous siphonage flow allowed replicate sampling and detection on one channel/device, obviating some possible inconsistencies among channels or devices. Y-shaped channels were fabricated with polyester cotton blend thread, due to its greater chemiluminescent sensitivity in comparison with that of cotton and polyester threads. S-μTAD sensors for glucose and uric acid were fabricated by using oxidase-immobilized cotton thread as the sample arm of the channels. The acceptable reproducibility and high sensitivity, demonstrated by the relative standard deviations of less than 5% in all cases and the detection limits of 4 × 10(-8) mol L(-1) for hydrogen peroxide, 1 × 10(-7) mol L(-1) for glucose, and 3 × 10(-6) mol L(-1) for uric acid, demonstrated the feasibility of the S-μTAD for quantitative assays. Good agreements between S-μTAD/sensor results and hospital results for blood glucose and uric acid assays indicated the capability of S-μTAD/sensors for the analysis of real samples. These findings proved the utility of siphonage for low-cost microfluidics and the suitability of our S-μTAD design for quantitative assays.
authors.affiliation: Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, 710062 Xi'an, China. lvjiagen@snnu.edu.cn jxdu@snnu.edu.cn.
authors.forename: Fang
authors.initials: F
authors.lastname: Lu
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Mao
authors.forename: Rui
authors.initials: R
authors.lastname: Wu
authors.forename: Shenghai
authors.initials: S
authors.lastname: Zhang
authors.forename: Jianxiu
authors.initials: J
authors.lastname: Du
authors.forename: Jiagen
authors.initials: J
authors.lastname: Lv
mesh_terms: D015374:Biosensing Techniques / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D001786:Blood Glucose / Q000032:analysis; D032561:Cotton Fiber; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D005947:Glucose / Q000032:analysis; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis; D046210:Microfluidic Analytical Techniques / Q000191:economics / Q000295:instrumentation*; D010088:Oxidoreductases / Q000737:chemistry / Q000378:metabolism; D015203:Reproducibility of Results; D014527:Uric Acid / Q000032:analysis
chemical_list: D001786:Blood Glucose; D004800:Enzymes, Immobilized; D014527:Uric Acid; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; D005947:Glucose