A highly photoluminescent small-size carbon dots (CDs) deriving ampicillin sodium were successfully obtained via one-step hydrothermal method. The prepared CDs showed uniform particle size and possessed good excitation-dependent characteristic. The dead bacteria and yeast cells could be selectively stained by the CDs, but the live ones not. It indicated that the CDs possessed a good potential for the live/dead bacteria and yeast differentiation. Cell and plant leave bioimaging showed that the prepared CDs possessed low biotoxicity, excellent biocompatibility and multicolor fluorescence emission properties making it a good candidate for bioimaging application. The probe exhibited high selectivity and sensitivity to detect Hg(II) and 2,4-dinitrophenol (2,4-DNP), and excellent linear range of 0–50 μM for Hg(II) (R² = 0.9920) and 0–25 μM for 2,4-DNP (R² = 0.9919), with low detection limits of 33.40 nM and 13.44 nM for Hg(II) and 2,4-DNP, respectively. It revealed that dynamic quenching mechanism dominated in Hg(II) quenching the CDs fluorescent, while the quenching mechanism of 2,4-DNP detection belonged to the inner filter effect. The sensor was successfully applied to determine the Hg(II) and 2,4-DNP in real water samples. It shows that the fluorescent nanoprobe shows great promising potential for application to environmental pollutants detection.

通过一步水热法成功获得了由氨苄西林钠衍生的高光致发光小尺寸碳点（CD）。所制备的CD显示出均匀的粒径，并具有良好的激发依赖性。死菌和酵母细胞可以被CD选择性染色，而活菌则不能。它表明CD具有活/死细菌和酵母分化的良好潜力。细胞和植物叶片的生物成像表明，所制备的CD具有较低的生物毒性，优异的生物相容性和多色荧光发射特性，使其成为生物成像应用的良好候选者。该探针对Hg（II）和2,4-二硝基苯酚（2,4-DNP）的检测具有很高的选择性和灵敏度，并且Hg（II）（R ²）的线性范围为0–50μM。 对于2,4-DNP（R ²  = 0.9919）= 0.9920）和0–25μM，对于Hg（II）和2,4-DNP的低检测限分别为33.40 nM和13.44 nM。结果表明，Hg（II）的动态猝灭机理主要是对CD荧光的猝灭，而2,4-DNP检测的猝灭机理则属于内滤作用。该传感器已成功应用于确定实际水样中的Hg（II）和2,4-DNP。结果表明，荧光纳米探针具有广阔的应用前景。