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As glucose biosensors play an important role in glycemic control, which can prevent the diabetic complications, the development of a glucose sensing platform is still in needed. Herein, the first proposal on the in-house fabricated paper-based screen-printed ionic liquid/graphene electrode (SPIL-GE) modified with MXene (Ti3C2Tx), prussian blue (PB), glucose oxidase (GOx), and Nafion is reported. The concentration of PB/Ti3C2Tx was optimized and the optimal detection potential of PB/Ti3C2Tx/GOx/Nafion/SPIL-GE is −0.05 V. The performance of PB/Ti3C2Tx/GOx/Nafion modified SPIL-GE was characterized by cyclic voltammetry and chronoamperometry technique. This paper-based platform integrated with nanomaterial composites were realized for glucose in the range of 0.0–15.0 mM with the correlation coefficient R2 = 0.9937. The limit of detection method and limit of quantification were 24.5 μM and 81.7 μM, respectively. In the method comparison, this PB/Ti3C2Tx/GOx/Nafion/SPIL-GE exhibits a good correlation with the reference hexokinase method. This novel glucose sensing platform can potentially be used for the good practice to enhance the sensitivity and open the opportunity to develop paper-based electroanalytical devices. [ABSTRACT FROM AUTHOR]

ABO blood group is the most important blood type system for transfusion medicine. A paper-based analytical device (PAD) for ABO blood typing has been proposed. The device was composed of Whatman No. 113 paper, an absorbent gel pad, and a 3D-printing cassette. The 3D-printing cassette contained two circular holes for display of letters “A” and “B” on the PAD. Whole blood was dropped onto hydrophilic letters A and B on the PAD, in which the anti-A and anti-B were pre-immobilized, respectively. An absorbent gel pad was used to adsorb excess blood sample and washing solution during the washing step. The particle size of agglutinated red blood cells (RBCs) could not be eluted out of the paper by the elution solution. In contrast, non-agglutinated RBCs were washed out by means of elution solution. The devices could be used for real blood samples in a wide range of hematocrit levels, 21-59%. Unknown blood group samples (n = 500) were identified by the developed device and the results were compared with the conventional method, revealing 100% accuracy. Because of its compact size with low-cost fabrication, the portable ABO blood typing device has great potential for point-of-care testing, particularly in developing countries. [ABSTRACT FROM AUTHOR]