The widespread application of pyriproxyfen (PPF) in agriculture has led to its accumulation in environmental and food samples, posing potential risks to environmental safety and human health. Therefore, a reliable and sensitive detection method is urgently needed. In this study, suitable PPF hapten was designed using computer analysis. A highly specific monoclonal antibody (mAb) against PPF was successfully developed, exhibiting a half-maximal inhibitory concentration of 1.55 ng/mL. Based on this antibody, a colloidal gold immune test strip was established for the on-site detection of PPF in lake water, soil, strawberries, and cabbage, achieving calculated limits of detection (cLOD) of 0.76, 1.87, 5.25, and 4.35 ng/mL, respectively. The spiked recovery rates ranged from 91.7% to 110.8%, with coefficients of variation between 2.17% to 8.71%. The detection results were consistent with those obtained using instrumental method, confirming that the developed colloidal gold immunochromatographic test strip (CGITS) enables accurate, rapid, and on-site detection of PPF in environmental and food samples.

Skin aging, marked by alterations in external appearance, internal function, and structure, is predominantly driven by oxidative stress and inflammatory responses. Chiral selenium (L-Se) and manganese dioxide (D-MnO₂) nanoparticles (NPs), modified by L-cysteine and D-gluconic acid, respectively, were developed for anti-aging. Circular dichroism (CD) spectra of L-Se and D-MnO₂ NPs showed the highest CD intensity of 145.3 ± 5.5 mdeg at 646 nm and 94.3 ± 4.9 mdeg at 552 nm, respectively. In vitro experiments showed that chiral L-Se NPs were oxidized to Se⁴⁺ in the presence of hydrogen peroxide, wherein Mn²⁺ and Mn⁴⁺ were in a dynamic state because a disproportionation reaction occurred between chiral D-MnO₂ NPs and hydrogen peroxide. Importantly, chiral L-Se and D-MnO₂ NPs showed scavenging reactive oxygen species (ROS) and multienzyme-like antioxidative activity. Living cell experiments demonstrated that the ROS level decreased 2.45-fold and the inflammatory factors level reduced about 2-fold after cotreatment with D-MnO₂ and L-Se NPs. The mechanism demonstrated that chiral NPs resisted aging by scavenging ROS and reducing inflammation, L-Se and D-MnO₂ NPs were mediated by the extracellular CD44 and CD147 transmembrane proteins, respectively, while L-Se NPs showed superior anti-inflammatory capability whereas D-MnO₂ NPs had stronger anti-oxidative property. Notably, the boosted ability of antioxidation and antiinflammation was successfully confirmed by experiments in vivo. These findings suggest that multiple chiral NPs highly enhance the anti-aging efficiency.

Paclitaxel (PTX), methotrexate (MTX), and 5-fluorouracil (5-FU) are commonly-used small molecule anti-tumor drugs for breast cancer. Unfortunately, drug resistance occurs with long-term treatment or excessive use, and the high concentrations of PTX, MTX, and 5-FU in patients may lead to side effects with dose-limiting toxicities, such as myelosuppression, hepatotoxicity, and peripheral neuropathy. Therefore, concentration monitoring of PTX, MTX, and 5-FU in clinical treatment is very important. We prepared highly sensitive and specific monoclonal antibodies using several haptens, and established a multiple paper-based sensor utilizing optical signals of gold nanoparticles, which simultaneously detected PTX, MTX, and 5-FU in human plasma or urine with 10 min. A portable scanner for quantitative detection in plasma and urine samples was used, and the calculated limit of detection (cLOD) values were 0.002 and 0.142 μg/mL for PTX, 0.187 and 0.976 ng/mL for MTX, and 0.057 and 0.128 μg/mL for 5-FU, respectively. In the recovery test, the recovery rates and the coefficient of variation were 85.84%–108.81% and 1.23%–8.80%, respectively, indicating the reliability and accuracy of the multiple gold immunochromatographic strip (GIS). In addition, for the determination of collected clinical plasma samples, the correlation between the test data of the multiple GIS and liquid chromatography–tandem mass spectrometry (LC–MS/MS) was good. Therefore, the developed multiple GIS could be applied to the rapid detection of PTX, MTX, and 5-FU in different clinical samples.