Trends und Entwicklungstendenzen in der Mischtechnik – Eindrücke und Schlaglichter der ACHEMA 2022

This contribution shows an important excerpt of the trends, tendencies, further developments and innovations in mixing technology presented at ACHEMA 2022, which, as one of the most important chemical and process engineering unit operations, is particularly important against the background of one of the ACHEMAs main topics “sustainability”. In addition to process solutions for different viscosity ranges, examples of stirring technology for liquid-phase systems, static and solid-state mixers, as well as individual, novel mixing systems from the laboratory to industrial scale are dealt with.     

Construction of Microfluidic Chip Structure for Cell Migration Studies in Bioactive Ceramics

Cell migration is an essential bioactive ceramics property and critical for bone induction, clinical application, and mechanism research. Standardized cell migration detection methods have many limitations, including a lack of dynamic fluid circulation and the inability to simulate cell behavior in vivo. Microfluidic chip technology, which mimics the human microenvironment and provides controlled dynamic fluid cycling, has the potential to solve these questions and generate reliable models of cell migration in vitro. In this study, a microfluidic chip is reconstructed to integrate the bioactive ceramic into the microfluidic chip structure to constitute a ceramic microbridge microfluidic chip system. Migration differences in the chip system are measured. By combining conventional detection methods with new biotechnology to analyze the causes of cell migration differences, it is found that the concentration gradients of ions and proteins adsorbed on the microbridge materials are directly related to the occurrence of cell migration behavior, which is consistent with previous reports and demonstrates the effectiveness of the microfluidic chip model. This model provides in vivo environment simulation and controllability of input and output conditions superior to standardized cell migration detection methods. The microfluidic chip system provides a new approach to studying and evaluating bioactive ceramics.     

Microfluidic-Generated Seeds for Gold Nanotriangle Synthesis in Three or Two Steps

Nanoparticle synthesis has drawn great attention in the last decades. The study of crystal growth mechanisms and optimization of the existing methods lead to the increasing accessibility of nanomaterials, such as gold nanotriangles which have great potential in the fields of plasmonics and catalysis. To form such structures, a careful balance of reaction parameters has to be maintained. Herein, a novel synthesis of gold nanotriangles from seeds derived with a micromixer, which provides a highly efficient mixing and simple parameter control is reported. The impact of the implemented reactor on the primary seed characteristics is investigated. The following growth steps are studied to reveal the phenomena affecting the shape yield. The use of microfluidic seeds led to the formation of well-defined triangles with a narrower size distribution compared to the entirely conventional batch synthesis. A shortened two-step procedure for the formation of triangles directly from primary seeds, granting an express but robust synthesis is further described. Moreover, the need for a thorough study of seed crystallinity depending on the synthesis conditions, which – together with additional parameter optimization – will bring a new perspective to the use of micromixers which are promising for scaling up nanomaterial production is highlighted.     

用于高分辨率成像的肺器官芯片构建及肺炎模型应用研究

肺是人体呼吸系统的重要组成部分,气道上皮是肺与外界接触的第一道屏障,参与抵御外来的颗粒物、病原体等,可将异物以痰的形式排出体外,对维护呼吸道正常功能起到至关重要的作用.常用的体外细胞培养模型和哺乳动物模型尚不能完全模拟人体肺-气道微环境,在人体细胞与病原体相互作用研究和药物研发应用方面具有一定的局限性.该研究设计制作了...     

聚(双环戊二烯-co-环辛二烯)微流控芯片的制备

本文报道了聚(双环戊二烯-co-环辛二烯)微流控芯片的制备方法。引入环辛二烯作为共聚单体,与双环戊二烯通过开环易位聚合制备得到弹性共聚物。当环戊二烯与环辛烯的质量比是1 : 1时,制得共聚物的力学性能接近于聚二甲基硅氧烷(PDMS),弹性共聚物具有较高的微尺寸结构成型精度。利用聚双环戊二烯半固化凝胶的反应特性,实现共聚物与聚双环戊二烯基底之间的稳定键合。共聚物微流控芯片可以通过类似于PDMS的连接方式,实现简单、高效的密封连接。利用共聚物微流控芯片制得单分散的微液滴,控制连续相的流速即可实现微液滴尺寸的调变。关键词：聚双环戊二烯共聚物；环辛烯；弹性体；微流控芯片；单分散液滴；中图分类号：TQ630 文献标识码： A 文章编号：1003-5214 (2020) 01-0000-00     

A continuous flow reactor for the flexible production of different formulations: CFD-aided design

The increasing need to improve the sustainability of industrial processes requires more flexible and intensified solutions. For this purpose, nowadays lots of efforts are made to switch from batch to continuous processes, the latter being able to ensure the same processing history to all fluid elements, with a consequent better control of the operating conditions and product quality. The present work aims at developing a continuous flow reactor for the production of several fine chemicals, including medical-surgical aids, but also other substances for specific industrial sectors. The plant is basically an inline reactor equipped with various static mixers and side inlets, and it is conceived to ensure on-site production. This is an important feature also in light of the recent COVID-19 pandemic, which asked for flexible and distributed production of chemicals. Numerical simulations based on computational fluid dynamics are employed to study the performance, in terms of pressure drops and degree of mixing, of different static mixers, that is, the Lightnin Inliner Series 50 and Ross low pressure drop (LPD), combining various elements of mixing and injections in different operating conditions in both laminar and turbulent regimes. The results highlighted how numerical simulations may represent a valid tool for supporting the detailed design of such flow reactors by allowing the evaluation of the optimal design solutions.     

Construction of Exosome SORL1 Detection Platform Based on 3D Porous Microfluidic Chip and its Application in Early Diagnosis of Colorectal Cancer

Exosomes are promising new biomarkers for colorectal cancer (CRC) diagnosis, due to their rich biological fingerprints and high level of stability. However, the accurate detection of exosomes with specific surface receptors is limited to clinical application. Herein, an exosome enrichment platform on a 3D porous sponge microfluidic chip is constructed and the exosome capture efficiency of this chip is ≈90%. Also, deep mass spectrometry analysis followed by multi-level expression screenings revealed a CRC-specific exosome membrane protein (SORL1). A method of SORL1 detection by specific quantum dot labeling is further designed and the ensemble classification system is established by extracting features from 64-patched fluorescence images. Importantly, the area under the curve (AUC) using this system is 0.99, which is significantly higher (p < 0.001) than that using a conventional biomarker (carcinoembryonic antigen (CEA), AUC of 0.71). The above system showed similar diagnostic performance, dealing with early-stage CRC, young CRC, and CEA-negative CRC patients.     

One-Step Formation of Targeted Liposomes in a Versatile Microfluidic Mixing Device

Targeted liposomes, as a promising carrier, have received tremendous attention in COVID-19 vaccines, molecular imaging, and cancer treatment, due to their enhanced cellular uptake and payload accumulation at target sites. However, the conventional methods for preparing targeted liposomes still suffer from limitations, including complex operation, time-consuming, and poor reproducibility. Herein, a facile and scalable strategy is developed for one-step construction of targeted liposomes using a versatile microfluidic mixing device (MMD). The engineered MMD provides an advanced synthesis platform for multifunctional liposome with high production rate and controllability. To validate the method, a programmed death-ligand 1 (PD-L1)-targeting aptamer modified indocyanine green (ICG)-liposome (Apt-ICG@Lip) is successfully constructed via the MMD. ICG and the PD-L1-targeting aptamer are used as model drug and targeting moiety, respectively. The Apt-ICG@Lip has high encapsulation efficiency (89.9 ± 1.4%) and small mean diameter (129.16 ± 5.48 nm). In vivo studies (PD-L1-expressing tumor models) show that Apt-ICG@Lip can realize PD-L1 targeted photoacoustic imaging, fluorescence imaging, and photothermal therapy. To verify the versatility of this approach, various targeted liposomes with different functions are further prepared and investigated. These experimental results demonstrate that this method is concise, efficient, and scalable to prepare multifunctional targeted liposomal nanoplatforms for molecular imaging and disease theranostics.     

When Super-Resolution Microscopy Meets Microfluidics: Enhanced Biological Imaging and Analysis with Unprecedented Resolution

Super-resolution microscopy is rapidly developed in recent years, allowing biologists to extract more quantitative information on subcellular processes in live cells that is usually not accessible with conventional techniques. However, super-resolution imaging is not fully exploited because of the lack of an appropriate and multifunctional experimental platform. As an important tool in life sciences, microfluidics is capable of cell manipulation and the regulation of the cellular environment because of its superior flexibility and biocompatibility. The combination of microfluidics and super-resolution microscopy revolutionizes the study of complex cellular properties and dynamics, providing valuable insights into cellular structure and biological functions at the single-molecule level. In this perspective, an overview of the main advantages of microfluidic technology that are essential to the performance of super-resolution microscopy are offered. The main benefits of performing super-resolution imaging with microfluidic devices are highlighted and perspectives on the diverse applications that are facilitated by combining these two powerful techniques are provided.