A smartphone-based point-of-care test for detection of Chlamydia trachomatis

 描述(由申请人提供)：意义：本项目的最终目标是一种CE标志、FDA批准和CLIA豁免的基于智能手机的快速(&lt；20分钟)护理点(POC)测试，以帮助诊断沙眼衣原体(CT)感染。CT感染是最常见的细菌性传播感染，美国每年有近300万新病例，相关成本超过24亿美元。未经治疗的妇女，主要是15-24岁的年龄组，有很高的风险出现严重的后遗症，包括盆腔炎、宫外孕和不孕症。CT感染可以通过一片药片治愈，但事实上，在多达10个受感染的男性和女性中，多达9个人没有症状，这就需要使用准确的检测方法对高危人群进行筛选。目前使用的核酸扩增技术(NAAT)价格昂贵，在样本收集和结果之间存在显著延迟，严重限制了它们在受不成比例影响的资源贫乏环境中的适用性。快速的POC检测可以通过实现当天的“检测和治疗”方法和立即通知合作伙伴来防止后遗症和遏制疾病传播。目前CT的POC检测以侧向血流试验(LFT)为基础，使用胶体金作为报告，具有95%的特异性，但由于其低(高)检出限(LOD)，临床敏感性较低(低至27%)。在这个项目中，Lighostics的专利“纳米荧光粉”，二氧化硅包裹的持久发光纳米颗粒，将被用作衣原体内毒素(CLP)免疫分析的LFT记者。在测试完成后(15分钟)，一次性LFT盒将由智能手机读取，使用廉价的手机壳状附件和软件应用程序，使其极具现场部署能力和家庭测试的吸引力。假设：我们假设，改进的纳米磷-LFT的LOD预计比胶体金-LFT低20-200倍，将导致临床敏感性接近NAAT，后者是&gt；95%的敏感性。初步结果：使用相同的亲和试剂，使用未经优化和多分散的纳米荧光粉，纳米磷-LFTs的分析灵敏度比胶体金-LFTs提高了20倍，使用iPhone进行高灵敏发光检测的可行性也是如此。具体目标：该项目的第一阶段交付将是一个经过分析和临床验证的设备原型。在目标1中，将优化纳米荧光粉-LFT参数和智能手机组件，以实现灵敏的CT检测。在目标2中，将通过分析敏感度、特异度和干扰研究，以及通过小规模的回溯性临床研究来评估优化设备原型的性能。通过与表面化学、STI、LFT和CLPS专家的合作或技术服务，这个第一阶段项目的成功将为第二阶段新的CT POC测试的设备集成和预期的临床测试奠定基础。它还将验证纳米磷-LFTs作为超灵敏分析物检测的平台技术，在需要更敏感的POC测试的各种关键医疗条件中具有潜在的应用。

 DESCRIPTION (provided by applicant): Significance: The ultimate goal of this project is a CE-marked, FDA-cleared and CLIA-waived rapid (<20 min) smartphone-based point-of-care (POC) test to aid the diagnosis of Chlamydia trachomatis (CT) infections. CT infections are the most common bacterial STI, with almost 3 million new cases in the US each year, and associated costs exceeding $2.4 billion. Untreated women, mostly in the 15-24 age group, are at a high risk of serious sequelae including pelvic inflammatory disease, ectopic pregnancy, and infertility. CT infections are curable with a single pill, but the fact that they are asymptomatic in up to 9 out o 10 infected men and women necessitates screening of high-risk populations using accurate testing methods. Currently used Nucleic Acid Amplification Techniques (NAATs) are expensive and have a significant delay between specimen collection and result, severely limiting their applicability in disproportionately affected resource poor settings. Rapid POC tests can prevent sequelae and curb disease transmission by enabling a same-day "test and treat" approach and immediate partner notification. Current POC tests for CT, based on the lateral flow test (LFT) and using colloidal gold as reporters, are > 95% specific, but have low clinical sensitivities (down to 27%) due to their poor (high) limit of detection (LOD). In this project, Luminostics' proprietary "nanophosphors", silica- encapsulated persistent luminescence nanoparticles, will be used as LFT reporters in an immunoassay for Chlamydial LPS (cLPS). Upon assay completion (<15 min), the disposable LFT cartridge will be readout by a smartphone using an inexpensive phone case-like attachment and software app, making it extremely field- deployable and attractive for home testing. Hypothesis: We hypothesize that the improved LOD of nanophosphor-LFTs, expected to be 20- to 200-fold lower than colloidal gold-LFTs, will result in clinical sensitivities approaching NAATs, which are >95% sensitive. Preliminary results: Using the same affinity reagents, a 20-fold improvement in analytical sensitivity of nanophosphor-LFTs over colloidal gold-LFTs has been demonstrated using unoptimized and polydisperse nanophosphors, as has the feasibility of highly sensitive luminescence detection using an iPhone. Specific Aims: The Phase I deliverable of this project will be an analytically and clinicaly validated device prototype. In Aim 1, nanophosphor-LFT parameters and smartphone components will be optimized for sensitive CT detection. In Aim 2, the performance of the optimized device prototype will be evaluated through analytical sensitivity, specificity, and interference studies, and through a small-scale retrospective clinical study. The success of this Phase I project, the odds of which are maximized by collaborations with or the technical services of surface chemistry, STI, LFT, and cLPS experts, will set the stage for device integration and prospective clinical testing of the new POC test for CT in Phase II. It will also validate nanophosphor-LFTs as a platform technology for ultrasensitive analyte detection, with potential applications in a variety of critical medical conditions that need more sensitive POC tests.