Fluorescence-guided imaging during surgery is a promising technique that is increasingly used to aid surgeons in identifying sites of tumor and surgical margins. Of the two types of fluorescent probes, always-on and activatable, activatable probes are preferred because they produce higher target-to-background ratios, thus improving sensitivity compared with always-on probes that must contend with considerable background signal. There are two types of activatable probes: 1) enzyme-reactive probes that are normally quenched but can be activated after cleavage by cancer-specific enzymes (activity-based probes) and 2) molecular-binding probes which use cancer targeting moieties such as monoclonal antibodies to target receptors found in abundance on cancers and are activated after internalization and lysosomal processing (binding-based probes). For fluorescence-guided intraoperative surgery, enzyme-reactive probes are superior because they can react quickly, require smaller dosages especially for topical applications, have limited side effects, and have favorable pharmacokinetics. Enzyme-reactive probes are easier to use, fit better into existing work flows in the operating room and have minimal toxicity. Although difficult to prove, it is assumed that the guidance provided to surgeons by these probes results in more effective surgeries with better outcomes for patients. In this review, we compare these two types of activatable fluorescent probes for their ease of use and efficacy.

中文翻译：

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荧光引导手术中的可激活荧光探针：实际考虑。

手术期间的荧光引导成像是一种有前途的技术，越来越多地用于帮助外科医生识别肿瘤和手术切缘的部位。在这两种类型的荧光探针中，始终开启和可激活的可激活探针是优选的，因为它们产生更高的靶与背景之比，从而与必须与相当大的背景信号竞争的始终开启的探针相比，提高了灵敏度。有两种类型的可激活探针：1）酶反应性探针，通常被淬灭，但在被癌症特异性酶切割后可以被激活（基于活性的探针）； 2）使用癌症靶向部分（例如单克隆抗体）的分子结合探针针对大量存在于癌症中的目标受体的抗体，并在内部化和溶酶体处理后被激活（基于结合的探针）。对于荧光引导的术中手术，酶反应性探针具有优越性，因为它们可以快速反应，需要更小剂量，尤其是局部应用，副作用有限，并且具有良好的药代动力学。酶反应探针更易于使用，更适合手术室中现有的工作流程，并且毒性最小。尽管很难证明，但可以推测，这些探头向外科医生提供的指导可导致更有效的手术，并为患者带来更好的结果。在这篇综述中，我们比较了这两种类型的可激活荧光探针的易用性和功效。并具有良好的药代动力学。酶反应探针更易于使用，更适合手术室中现有的工作流程，并且毒性最小。尽管很难证明，但可以推测，这些探头向外科医生提供的指导可导致更有效的手术，并为患者带来更好的结果。在这篇综述中，我们比较了这两种类型的可激活荧光探针的易用性和功效。并具有良好的药代动力学。酶反应探针更易于使用，更适合手术室中现有的工作流程，并且毒性最小。尽管很难证明，但可以推测，这些探头向外科医生提供的指导可导致更有效的手术，并为患者带来更好的结果。在这篇综述中，我们比较了这两种类型的可激活荧光探针的易用性和功效。