Novel sampling matrices were manufactured using 3D printing for the detection of respiratory pathogens in expired air. A specific configuration of the matrices was designed using Computer-Aided Design software. Polyvinyl alcohol (PVA) was printed using fused deposition modelling to create a multilayer matrix to enhance the capture of bacteria. The performance of these matrices was compared with gelatine filters that have been used for this work to date. PVA matrices (60 mm diameter) were contaminated with bacteria either by direct inoculation, or by aerosol exposure using an Omron A3 nebuliser. Rough and smooth morphotypes of Mycobacterium abscessus, M. smegmatis and M. bovis BCG, were used in this study to contaminate the matrices. PVA matrices and gelatine sampling filters were contaminated to compare recovery rates for quantitative analyses. These were dissolved in water, bacteria pelleted and DNA extracted followed by a Mycobacterium-specific quantitative Polymerase Chain Reaction (qPCR).The results showed that 3D printed PVA matrices are very effective to capture the bacteria. 3D printed PVA matrix and gelatine filters yielded results of the same order of magnitude for mycobacterial analyses, however, PVA matrix offers several advantages over the latter material. 3D printed PVA is considered as an economic and time-effective matrix as it is cheaper than gelatine filters. PVA is sufficiently robust to be handled and loaded into the surgical masks for sampling, compared to the brittle gelatine filters that required supportive frames. PVA is a synthetic material and it is suitable for DNA-based analyses, whilst gelatine is derived from animal collagen, and carries a high bacterial DNA background that interferes with the target DNA analysis. Furthermore, PVA dissolves in distilled water without requiring chemicals or enzymes, such as the case for gelatine hydrolysis. To summarise, 3D printed PVA sampling matrix is considered a promising tool used for microbiological diagnostic purposes.

使用3D打印制造了新颖的采样矩阵，用于检测呼出空气中的呼吸道病原体。使用计算机辅助设计软件设计了矩阵的特定配置。使用熔融沉积模型印刷聚乙烯醇（PVA），以创建多层基质以增强细菌的捕获。将这些基质的性能与迄今为止用于这项工作的明胶过滤器进行了比较。通过直接接种或使用Omron A3雾化器进行气雾剂暴露，PVA基质（直径60毫米）被细菌污染。脓肿分枝杆菌，耻垢分枝杆菌和牛分枝杆菌的粗糙和光滑形态型本研究中使用了BCG来污染基质。PVA基质和明胶采样过滤器被污染，以比较回收率以进行定量分析。将它们溶解在水中，沉淀细菌，提取DNA，然后分枝杆菌提取特异性定量聚合酶链反应（qPCR）。结果表明3D打印的PVA基质对捕获细菌非常有效。3D打印的PVA基质和明胶过滤器对于分枝杆菌分析产生的结果数量级相同，但是，PVA基质比后者更具有优势。3D打印的PVA比明胶过滤器便宜，因此被认为是经济且省时的基质。与需要支撑框架的脆性明胶滤光片相比，PVA具有足够的强度，可以处理并装入手术口罩中进行采样。PVA是一种合成材料，适用于基于DNA的分析，而明胶则来源于动物胶原蛋白，并具有较高的细菌DNA背景，会干扰目标DNA的分析。此外，PVA溶于蒸馏水而无需化学药品或酶，例如明胶水解的情况。总而言之，3D打印的PVA采样矩阵被认为是用于微生物诊断的有前途的工具。