Heparin has been in clinical use as an anticoagulant for the last eight decades and used worldwide in more than 100 million medical procedures every year. This lifesaving drug is predominantly obtained from ~700 million pig intestines or bovine organs through millions of small and medium-sized slaughterhouses. However, the preparations from animal sources have raised many safety concerns, including the contamination of heparin with potential pathogens, proteins, and other impurities. In fact, contaminated heparin preparations caused 149 deaths in several countries, including the United States, Germany, and Japan in 2008, highlighting the need for implementing sensitive and simple analytical techniques to monitor and safeguard the heparin supply chain. The contaminant responsible for the adverse effects in 2008 was identified as oversulfated chondroitin sulfate (OSCS). We have developed a very sensitive, facile method of detecting OSCS in heparin lots using a nanosensor, a gold nanoparticle–heparin dye conjugate. The sensor is an excellent substrate for heparitinase enzyme, which cleaves the heparin polymer into smaller disaccharide fragments, and therefore facilitates recovery of fluorescence from the dye upon heparitinase treatment. However, the presence of OSCS results in diminished fluorescence recovery from the nanosensor upon heparitinase treatment, because OSCS inhibits the enzyme. The newly designed nanosensor can detect as low as 1 × 10^–9% (w/w) OSCS, making it the most sensitive tool available to date for the detection of trace amounts of OSCS in pharmaceutical heparins. In this report, we describe a simple methodology for the preparation of nanosensor and its application in the detection of OSCS contaminants.

在过去的八年里，肝素一直作为抗凝剂用于临床，每年在全球范围内用于超过 1 亿次医疗程序。这种救命药物主要是通过数百万个中小型屠宰场从约 7 亿个猪肠或牛器官中获得。然而，动物来源的制剂引起了许多安全问题，包括潜在病原体、蛋白质和其他杂质对肝素的污染。事实上，2008 年受污染的肝素制剂在包括美国、德国和日本在内的多个国家造成 149 人死亡，凸显了实施敏感和简单的分析技术来监测和保护肝素供应链的必要性。2008 年造成不良影响的污染物被确定为过度硫酸化的硫酸软骨素 (OSCS)。我们开发了一种非常灵敏、简便的方法，可使用纳米传感器（一种金纳米颗粒 - 肝素染料偶联物）检测肝素批次中的 OSCS。该传感器是肝素酶的极好底物，肝素酶将肝素聚合物切割成更小的二糖片段，因此有助于在肝素酶处理后从染料中恢复荧光。然而，OSCS 的存在导致肝素酶处理后纳米传感器的荧光恢复减弱，因为 OSCS 抑制酶。新设计的纳米传感器可检测低至 1×10 金纳米颗粒-肝素染料偶联物。该传感器是肝素酶的极好底物，肝素酶将肝素聚合物切割成更小的二糖片段，因此有助于在肝素酶处理后从染料中恢复荧光。然而，OSCS 的存在导致肝素酶处理后纳米传感器的荧光恢复减弱，因为 OSCS 抑制酶。新设计的纳米传感器可检测低至 1×10 金纳米颗粒-肝素染料偶联物。该传感器是肝素酶的极好底物，肝素酶将肝素聚合物切割成更小的二糖片段，因此有助于在肝素酶处理后从染料中恢复荧光。然而，OSCS 的存在导致肝素酶处理后纳米传感器的荧光恢复减弱，因为 OSCS 抑制酶。新设计的纳米传感器可检测低至 1×10 因为 OSCS 抑制酶。新设计的纳米传感器可检测低至 1×10 因为 OSCS 抑制酶。新设计的纳米传感器可检测低至 1×10^–9 % (w/w) OSCS，使其成为迄今为止可用于检测药用肝素中痕量 OSCS 的最灵敏的工具。在本报告中，我们描述了一种制备纳米传感器的简单方法及其在检测 OSCS 污染物中的应用。