Highly sensitive and quantitative fluorescent lateral flow strip sensor for heart failure detecting based on dual-color upconversion microparticles

ANP (atrial natriuretic peptide) and BNP (brain natriuretic peptide) are important indicators for detecting heart failure (HF). However, traditional testing method had low real-time detecting and poor sensitivity, which limited the early diagnosis of HF. Herein, we prepare a low cost device based on upconversion microparticles (UCMPs) with porous structure, which has a high detecting sensitivity for ANP and BNP markers. The lowest detection concentration of ANP and BNP can reach 5 pg/mL with Yb/Tm/Sr/12CaO·7Al2O3 (Yb/Tm/Sr/C12A7)-LFS and Yb/Er/Sr/C12A7-LFS, which are of one order lower than their clinical cutoff. The whole UCL intensity of UCMPs enhanced via Sr2+ ions doping. UCMPs not only have dual-color UCL, but also achieve good temperature sensing. The maximum SR of Yb/Tm/Sr/C12A7 and Yb/Er/Sr/C12A7 based on UCL ratio are 4.23 % K−1 and 3.36 % K−1, respectively. The UCMPs-LFS device has a low-cost laser diode, simplified laser and permits a mobile phone camera to collect the imaging, which is benefit for detecting ANP and BNP application.