A microbial biosensor is an analytical device with a biologically integrated transducer that generates a measurable signal indicating the analyte concentration. This method is ideally suited for the analysis of extracellular chemicals and the environment, and for metabolic sensory regulation. Although microbial biosensors show promise for application in various detection fields, some limitations still remain such as poor selectivity, low sensitivity, and impractical portability. To overcome such limitations, microbial biosensors have been integrated with many recently developed micro/nanotechnologies and applied to a wide range of detection purposes. This review article discusses micro/nanotechnologies that have been integrated with microbial biosensors and summarizes recent advances and the applications achieved through such novel integration. Future perspectives on the combination of micro/nanotechnologies and microbial biosensors will be discussed, and the necessary developments and improvements will be strategically deliberated.

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Various materials are fabricated to form specific structures/patterns at the micro‐/nanoscale, which exhibit additional functions and performance. Recent liquid‐mediated fabrication methods utilizing bottom‐up approaches benefit from micro‐/nanofluidic technologies that provide a high controllability for manipulating fluids containing various solutes, suspensions, and building blocks at the microscale and/or nanoscale. Here, the state‐of‐the‐art micro‐/nanofluidic approaches are discussed, which facilitate the liquid‐mediated patterning of various hybrid‐scale material structures, thereby showing many additional advantages in cost, labor, resolution, and throughput. Such systems are categorized here according to three representative forms defined by the degree of the free‐fluid–fluid interface: free, semiconfined, and fully confined forms. The micro‐/nanofluidic methods for each form are discussed, followed by recent examples of their applications. To close, the remaining issues and potential applications are summarized.

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Three-dimensional (3D)-printed in vitro tissue models have been used in various biomedical fields owing to numerous advantages such as enhancements in cell response and functionality. In liver tissue engineering, several studies have been reported using 3D-printed liver tissue models with improved cellular responses and functions in drug screening, liver disease, and liver regenerative medicine. However, the application of conventional single-component bioinks for the printing of 3D in vitro liver constructs remains problematic because of the complex structural and physiological characteristics of the liver. The use of multicomponent bioinks has become an attractive strategy for bioprinting 3D functional in vitro liver tissue models because of the various advantages of multicomponent bioinks, such as improved mechanical properties of the printed tissue construct and cell functionality. Therefore, it is essential to review various 3D bioprinting techniques and multicomponent hydrogel bioinks proposed for liver tissue engineering to suggest future directions for liver tissue engineering. Accordingly, we herein review multicomponent bioinks for 3D-bioprinted liver tissues. We first describe the fabrication methods capable of printing multicomponent bioinks and introduce considerations for bioprinting. We subsequently categorize and evaluate the materials typically utilized for multicomponent bioinks based on their characteristics. In addition, we also review recent studies for the application of multicomponent bioinks to fabricate in vitro liver tissue models. Finally, we discuss the limitations of current studies and emphasize aspects that must be resolved to enhance the future applicability of such bioinks.

Diffusioosmosis (DO) results from ion transport near charged surfaces in the presence of electrolyte gradients and is critical in nanofluidic systems. However, DO has not yet been comprehensively studied because nanofabrication materials have limitations of low throughput and difficult quantification. Herein, we describe a self-assembled particle membrane (SAPM)-integrated microfluidic platform that can modulate the material properties (e.g., zeta-potential) and transport flux of nanopores. We quantify the effect of the zeta-potential on DO by measuring the electrical signals across three different nanopores/nanochannels of the SAPM. We then empirically quantify the effects of the temperature and ionic strength of the electrolytes on DO and reveal a nonlinear relationship with DO-driven ion transport; the ionic strengths govern the DO-or diffusion-effective ion transport phenomena. Finally, we demonstrate DO-driven electric power generation with enhanced performance as a potential application under optimized experimental conditions.

Because of their unique advantages, non‐woven nanofibrous mats are now being widely used in various fields. Accordingly, a variety of fabrication techniques have been proposed for manufacturing these mats. Electrospinning has emerged as one of the most popular methods for fabricating nanofibers. However, the whipping motion of the electrospinning jet of conventional electrospinning imposes a knotty limitation on the geometric control. Thus, when nanofibrous mats are fabricated via electrospinning, geometric uniformity cannot be assured, and this can significantly affect the performance, quality, and reliability of their applications. In this study, a direct‐write electrospinning‐based fabrication method for nanofibrous mats that provides greater overall thickness and fiber‐density uniformity is proposed. Various nanofibrous mats fabricated via the proposed method are presented, and their morphological and mechanical properties are experimentally investigated. The fabricated nanofibrous mats exhibit better thickness and fiber‐density uniformity, and their mechanical properties are controllable.

This study investigates whether higher start-up intention leads to innovative behavior and whether innovative behavior is increased by the medium of entrepreneurship. This study tested the hypotheses by conducting a survey on students participating in entrepreneurship club activities in university. The results showed that start-up intention affects innovative behavior and has a significant effect on the sub-factors of entrepreneurship, such as innovation, risk taking, and proactiveness. The result of an analysis of the mediating effect of entrepreneurship on innovative behavior showed that all sub-factors performed a partially mediating role. It can therefore be said that higher start-up intention leads to more innovative behavior and that entrepreneurship serves as an important link in this relationship. These results show that increasing start-up intention may lead to innovative behavior and imply that this has educational relevance in cultivating entrepreneurship. However, this study is limited in terms of the generalizability of the results, as the subjects are university students participating in entrepreneurship club activities in Korea. Therefore, more significant outcomes can be obtained in further research by targeting a broader scope of subjects.