Kimoto Hiroshi, Suzuki Yota, Ebisawa Yu, Iiyama Masamitsu, Hashimoto Takeshi, Hayashita Takashi
Department of Materials and Life Sciences, Faculty of Science and Technology, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554, Japan.
Technical Development Division, Nomura Micro Science Co., Ltd., 2-4-37 Okada, Atsugi, Kanagawa 243-0021, Japan.
ACS Omega. 2022 Jul 15;7(29):25891-25897. doi: 10.1021/acsomega.2c02935. eCollection 2022 Jul 26.
Endotoxin is a lipopolysaccharide (LPS) that is found in the outer membrane of the cell wall of Gram-negative bacteria. Due to its high toxicity, the allowable endotoxin limit for water for injection is set at a very low value. Conventional methods for endotoxin detection are time-consuming and expensive and have low reproducibility. A previous study has shown that dipicolylamine ()-modified pyrene-based probes exhibit fluorescence enhancement in response to LPS; however, the application of such probes to the sensing of LPS is not discussed. Against this backdrop, we have developed a simple and rapid endotoxin detection method using a -modified pyrenyl probe having a zinc(II) center (). When LPS was added into solution, excimer emission of the pyrene moiety emerged at 470 nm. This probe can detect picomolar concentrations of LPS (limit of detection = 41 pM). The high sensitivity of the probe is ascribed to the electrostatic and hydrophobic interactions between the probe and LPS, which result in the dimer formation of the pyrene moieties. We also found that has the highest selectivity for LPS compared with other phosphate derivatives, which is probably caused by the co-aggregation of the probe with LPS. We propose that is a promising chemical sensor for the detection of endotoxin in medical and pharmaceutical applications.
内毒素是一种脂多糖（LPS），存在于革兰氏阴性菌细胞壁的外膜中。由于其高毒性，注射用水的内毒素允许限量设定得非常低。传统的内毒素检测方法耗时且昂贵，重现性低。先前的一项研究表明，二吡啶甲胺修饰的芘基探针在响应LPS时会出现荧光增强；然而，此类探针在LPS传感中的应用尚未被讨论。在此背景下，我们开发了一种使用具有锌（II）中心的修饰芘基探针的简单快速的内毒素检测方法。当将LPS添加到溶液中时，芘部分的激基缔合物发射出现在470 nm处。该探针可以检测皮摩尔浓度的LPS（检测限 = 41 pM）。该探针的高灵敏度归因于探针与LPS之间的静电和疏水相互作用，这导致芘部分形成二聚体。我们还发现，与其他磷酸盐衍生物相比，对LPS具有最高的选择性，这可能是由于探针与LPS的共聚集所致。我们认为是一种用于医疗和制药应用中内毒素检测的有前途的化学传感器。
