呼吸道感染病是全球病例死亡的主要原因之一，目前由新冠病毒引起的新冠肺炎在世界范围流行，对公众健康造成巨大威胁。快速准确的诊断检测方法和有效的治疗技术是防控呼吸道感染病的关键。目前呼吸道感染病采样主要方法是鼻拭子或咽拭子，然后进行核酸检测分析。与鼻咽拭子相比，呼出气气溶胶采集是一种非侵入性的方法，可以减少受试者的不适感，并降低医护人员感染风险。现有的呼出气气溶胶采样器存在采集效率较低和病毒生物活性保存率低等问题，限制了呼出气气溶胶样本在疾病诊断中的应用。论文基于“冷凝生长+旋风采集”原理研制新型呼出气气溶胶采样器，搭建评测系统表征了其性能，发现采样器对100纳米聚α乙烯油气溶胶的采集效率可达 68.1%，表明该采样器可以有效采集亚微米呼出气气溶胶；对Phi6噬菌体的活性保存效率为93.5%，表明该采样器能够有效维持病毒活性以进行检测分析；样品采集速率为248.7 μL/min，表明该采样器在1分钟内即可采集到足够的样本供后续RT-qPCR核酸分析。应用该采样器采集呼吸道感染病患者的呼出气气溶胶样本，成功识别了腺病毒和流感病毒，同咽拭子样品检测结果吻合。相较于注射和口服药物治疗新冠肺炎等呼吸道感染病，基于气溶胶的吸入给药能快速地将药物输运到呼吸道感染区，有望在实现便捷给药的同时提高治疗效果，并降低药物用量及其潜在副作用。论文研制了药物气溶胶发生装置和给药系统，以新研发治疗新冠肺炎的纳米抗体药物为例，对药物气溶胶发生和给药系统进行了评测，并在生物安全三级实验室评估了纳米抗体药物气溶胶给药对小鼠新冠肺炎的防护效果。发现所发生的纳米抗体药物气溶胶质量浓度中值粒径约为2微米，所发生的药物气溶胶具有良好的稳定性和可调节性。小鼠肺部纳米抗体药物的沉积量与雾化液中纳米抗体浓度呈较好的比例关系，表明纳米抗体气溶胶成功沉积在小鼠肺部。雾化前后纳米抗体的中和能力无显著变化。发现气溶胶给药在使用更低药物剂量前提下实现与滴鼻给药相当的效果，显著降低小鼠肺部新冠病毒滴度。
Respiratory infection was listed as one of key killers. Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was widespread around the world, threating public health. Rapid, accurate diagnosis method and effective therapeutics are essential to control the spread of COVID-19. At present, specimen collection methods of respiratory infections include nasal swabs and throat swabs, and then specimen is analyzed via nucleic acid testing. Compared with nasal swabs and throat swabs, exhaled aerosol collection is a non-invasive method, which reduces discomfort in subjects and the risk of infection in healthcare workers. The collection efficiencies and viral infectivity conservation efficiencies of current exhaled breath devices are relatively low, so development of a new sampler is in need. In this study, a novel exhaled breath sampler was developed based on condensational growth and cyclone centrifugation and experimental results showed that the collection efficiency for 100 nm test aerosols is 68.1%, which indicates that it can efficiently collect exhaled bioaerosols. Phi6 infectivity conservation efficiency was tested to be 93.5%, which means that it effectively preserves their infectivity for culture experiment. Its higher sample collection rate can reduce the collection time and make it feasible for deployment. Besides, adenoviruses and influenza B viruses were detected in exhaled breath of patients with respiratory disease, which agree with the detection results of nasal swab.Compared with drug delivery via oral and intravenous route for therapies of patients with COVID-19 and other respiratory infections, drug delivery via aerosol can permeate into the sites of lung infection more conveniently and efficiently, has the potential to improve curative effect, reduce side effect and administration dosage. In this study, an aerosol generator and delivery system were developed and their aerosol characteristics was characterized by nebulizing newly developed nanobody designed for COVID-19 treatment. And then the in vivo therapeutics and prophylactic efficacy of nanobodies against SARS-CoV-2 in mice were evaluated in biological safety protection third-level laboratory. Experimental results showed that the mass median aerosol diameter of atomized nanobodies was about 2 μm. The concentrations of nanobodies were uniformly distributed across different places inside the chamber and maintained stability during long-term exposure durations. Besides, the nanobodies mass deposited in the lungs of mice was directly proportional to the concentration of nanobodies in the atomized solution, indicating that nanobodies was successfully permeated into the lungs of mice and deposited. The aerosolization processing did not influence the neutralization activities of the nanobodies against SARS-CoV-2 pseudoviruses. The lung viral RNAs of mice decreased equally when nanobody was delivered via intranasal and inhalational routes and the administrated dose via the inhalational route was lower than via the intranasal route
