Existing Printing Methods Research Articles

Hybrid Printing of Fully Integrated Microfluidic Devices for Biosensing.

The advent of 3D printing has facilitated the rapid fabrication of microfluidic devices that are accessible and cost-effective. However, it remains a challenge to fabricate sophisticated microfluidic devices with integrated structural and functional components due to limited material options of existing printing methods and their stringent requirement on feedstock material properties. Here, a multi-materials multi-scale hybrid printing method that enables seamless integration of a broad range of structural and functional materials into complex devices is reported. A fully printed and assembly-free microfluidic biosensor with embedded fluidic channels and functionalized electrodes at sub-100µm spatial resolution for the amperometric sensing of lactate in sweat is demonstrated. The sensors present a sensitive response with a limit of detection of 442nm and a linear dynamic range of 1-10mm, which are performance characteristics relevant to physiological levels of lactate in sweat. The versatile hybrid printing method offers a new pathway toward facile fabrication of next-generation integrated devices for broad applications in point-of-care health monitoring and sensing.

Lightweight 3D bioprinting with point by point photocuring

As photocrosslinkable materials, methacryloyl-modified hydrogels are widely used as bioinks in tissue engineering. Existing printing methods to use these hydrogels, including changing the viscosity of the material or mixing them with other printing components, have been explored, but their application has been limited due to low printing quality or high cost. In addition, the complex operation of bulky equipment restricts the application of these existing printing methods. This study presents a lightweight stereolithography-based three-dimensional (3D) bioprinting system with a smart mechanical and structural design. The developed bioprinter dimensions were 300 mm × 300 mm × 200 mm and it can be placed on a benchtop. The equipment has a mini bioink chamber to store a small amount of bioink for each printing. We systematically investigated the point-by-point curing process in the 3D bioprinting method, which can print mixed cells accurately and have good biocompatibility. Here, we provide a compact, low-cost stereolithography bioprinting system with excellent biocompatibility for 3D bioprinting with methacryloyl-modified hydrogels. It can be potentially used for drug screening, studying pathological mechanisms, and constructing biological disease models.

PRESERVATION, STUDY AND POPULARIZATION OF BOOK HERITAGE IN IRKUTSK ("ACADEMIA" PUBLISHING HOUSE COLLECTION)

"Academia" Publishing House (1922–1937) books are an example of high publishing culture.For many years, the products of the publishing house have been the subject of close attention on the part of bibliophiles and collectors in many countries of the world. The reason for this interest is literary impeccability and excellent decoration. To reach unprecedented artistic heights became possible thanks to the work of the best Soviet professional artists. All the existing printing methods, the best printing houses, and graphic art techniques were used while creating these books. The history of the publishing house, covered in rare publications, alongside with triumphal events, victories at international book competitions, is full of dramatic and even tragic pages. It can be called the publishing house of repressed editors, authors, and books.Almost all the managers of Academia, many employees were subjected to repressions, were sentenced to capital punishment. Their names were extorted from the output of the entire book circulation; introductory articles were cut out, publications were discontinued, sometimes, entire print runs of books were destroyed. In modern libraries, copies of such "repressed" books have been miraculously preserved. That is why it is difficult to overestimate their historical and cultural value – genuine documentary witnesses of historical events of almost a century remoteness.The history of the Academia Publishing House is intertwined with Irkutsk, since the stuff included people whose fate related to the city on the Angara: the last head of the “Academia”, Yakov Davidovich Yanson, after the October revolution held leadership positions in the government in Irkutsk; the founder of the Soviet school of folklore and anthrax studies, Irkutsk professor Mark Konstantinovich Azadovsky also collaborated with the publishing house “Academia”.The article is the first to observe the questions of valuable collections formation and preservation in the Irkutsk Regional Universal Scientific Library named after I. I. Molchanov-Sibirsky (IRSUSL), the former library of the Irkutsk Pedagogical Institute and the library of the Irkutsk Regional Art Museum named after V. P. Sukatchev (IRAM). Collecting bit-by-bit book masterpieces, librarians study, popularize them at exhibitions, presentations, lectures, showing the authentic Russian book art culture.

4D printing: a critical review of current developments, and future prospects

Due to the strong demand for low-cost and highly efficient products, various approaches are currently being explored and applied so as to contribute to the development and optimization of 4D printing technology. Significant progress is being made in this area of advanced manufacturing, and this comparative study helps to understand the latest developments in materials, additive techniques, and future prospects for this technology. It should, however, be noted that a large amount of progress still remains to be made. While some of the research has focused on the performance of the materials, the rest has focused on the development of new methods and techniques in additive manufacturing. This review critically evaluates the current 4D printing technologies, including the development and optimization of printing methods as well as to the printed objects. Previous developments in this area and contributions to the modern trend in manufacturing technology are briefly summarized. The review is divided into three sections. Firstly, the existing printing methods along with the frequently used printing materials as well as the processing parameters, and the factors which influence the quality and mechanical performances of the printed objects are discussed. Secondly, the optimization techniques, such as topology, shape, structure, and mechanical property, are described. Thirdly, the latest development and applications of additive manufacturing are depicted, and suggestions concerning the scope of future research are put forward.

A review of 3D concrete printing systems and materials properties: current status and future research prospects

PurposeThree-dimensional printing of concrete (3DPC) has a potential for the rapid industrialization of the housing sector, with benefits of reduced construction time due to no formwork requirement, ease of construction of complex geometries, potential high construction quality and reduced waste. Required materials adaption for 3DPC is within reach, as concrete materials technology has reached the point where performance-based specification is possible by specialists. This paper aims to present an overview of the current status of 3DPC for construction, including existing printing methods and material properties required for robustness of 3DPC structures or structural elements.Design/methodology/approachThis paper has presented an overview of three categories of 3DPC systems, namely, gantry, robotic and crane systems. Material compositions as well as fresh and hardened properties of mixes currently used for 3DPC have been elaborated.FindingsThis paper presents an overview of the state of the art of 3DPC systems and materials. Research needs, including reinforcement in the form of bars or fibres in the 3D printable cement-based materials, are also addressed.Originality/valueThe critical analysis of the 3D concrete printing system and materials described in this review paper is original.

3D bioprinting technology for regenerative medicine applications

 Alternative strategies that overcome existing organ transplantation methods are of increasing importance because of ongoing demands and lack of adequate organ donors. Recent improvements in tissue engineering techniques offer improved solutions to this problem and will influence engineering and medicinal applications. Tissue engineering employs the synergy of cells, growth factors and scaffolds besides others with the aim to mimic the native extracellular matrix for tissue regeneration. Three-dimensional (3D) bioprinting has been explored to create organs for transplantation, medical implants, prosthetics, in vitro models and 3D tissue models for drug testing. In addition, it is emerging as a powerful technology to provide patients with severe disease conditions with personalized treatments. Challenges in tissue engineering include the development of 3D scaffolds that closely resemble native tissues. In this review, existing printing methods such as extrusion-based, robotic dispensing, cellular inkjet, laser-assisted printing and integrated tissue organ printing (ITOP) are examined. Also, natural and synthetic polymers and their blends as well as peptides that are exploited as bioinks are discussed with emphasis on regenerative medicine applications. Furthermore, applications of 3D bioprinting in regenerative medicine, evolving strategies and future perspectives are summarized.

Cell-compatible, multicomponent protein arrays with subcellular feature resolution.

Recent developments in micro/nano-scale technology have enabled the generation of extracellular matrix (ECM) protein microarrays with well-defined geometries. These patterned surfaces have shown utility for the study and control of a variety of cellular behaviors.[1–7] In particular, the patterning of proteins with feature sizes smaller than a single cell have demonstrated potential application for use as tools to control cellular activity.[4, 8] To date, most research has been limited to studies with single protein factors due to technical limitations of existing printing methods. Herein, we describe the development of a microscale direct writing (MDW) technology for the generation of complex ECM protein arrays at subcellular feature size with multiple components. Automated printing techniques based on atomic force microscopy were developed to allow programmable generation of cell-compatible surfaces with multiple ECM proteins, at a subcellular feature size of 6–9 microns. Cell-compatible, two component ECM protein arrays were systematically generated with varying spacing and composition. These arrays were then studied for their effects on cellular attachment and spreading of a model cell line, human myofibroblasts. Interestingly, the precise tuning of spacing and placement two components at subcellular resolution can lead to an increase in cellular alignment. Given the complexity of the in vivo cellular microenvironment, we believe the MDW methods described here could prove generally applicable for the study and optimization of biomaterial surfaces.