Search

Agomelatine (AGM) is an effective antidepressant with low oral bioavailability due to intensive hepatic metabolism. Transdermal administration of agomelatine may increase its bioavailability and reduce the doses necessary for therapeutic effects. However, transdermal delivery requires crossing the stratum corneum barrier. For this purpose, the use of microneedles may increase the efficiency of administration. The aim of this study was to prepare an agomelatine-loaded hydrogel suitable for coating microneedles for the transdermal drug delivery of AGM. The optimized formulations were subjected to spectroscopic and rheological characterization and mechanical tests, as well as tested for release through an artificial membrane and permeation through human skin ex vivo. Both hydrogels were found to have suitable parameters for coating microneedles using the dip-coating method, including the stability of the substance at the process temperature, shear-thinning behavior, and appropriate textural parameters such as adhesion or hardness. Additionally, two formulations were tested for potential application to the skin alone because the gels showed suitable mechanical properties for the skin application. In this case, the ethanol gel was characterized by higher skin permeability and better spreadability. The information obtained in this study will allow the preparation of coated microneedles for the transdermal administration of agomelatine.

This study investigates the energy consumption characteristics of desktop-sized Fused Filament Fabrication (FFF) 3D printers, focusing on variations in energy usage and operational efficiency across different models. The results demonstrate a correlation between machine parameters and energy efficiency during the processing of PLA material. Notably, machines capable of producing identical components in shorter durations tend to consume more electricity, despite utilizing a lower volume of thermoplastic material. Furthermore, the research underscores the substantial impact of specific technological factors, such as the use of rafts, on energy consumption assessments. Relying solely on estimated manufacturing time and material volume to determine manufacturing costs may yield imprecise results, especially amid rising electricity prices. This study emphasizes the need for standardized energy metrics to enable more informed comparisons for consumers.

The aim of the study was to investigate the effect of ethanol on the properties of acrylic-urethane resin products obtained by vat photopolymerization using the masked stereolithography method. The effect of alcohol at concentrations of 15, 25, and 35% in the resin on the chemical structure, weight, thickness of the samples, and mechanical properties in static tabltensile tests performed immediately after printing and one month later were studied. The results obtained were evaluated in terms of the use of ethanol as a cosolvent to help load the resin with agomelatine for the potential of obtaining microneedle transdermal systems. It was shown that in terms of stability of properties, the most favorable system was resin with the addition of alcohol at a concentration of 15%. The greatest changes induced by the presence of the solvent in the resin were observed in the case of tensile properties, where the alcohol caused a decrease in the plasticity of the material, reducing the relative elongation at break from 14% for the pure resin to 4% when the alcohol concentration was 35%. Young’s modulus and tensile strength also decreased with the addition of alcohol by 18% and 31%, respectively, for testable samples with the maximum amount of alcohol in the resin. The deterioration in properties is most likely related to the effect of the solvent on the radical polymerization process of the resin, particularly the phenomenon of chain transfer to the solvent, which is important in view of the intended application of the developed material.

Advancements in materials science and 3D printing technologies have opened up new avenues for developing low-cost robotic grippers with high-performance capabilities, making them suitable for various biomechatronic applications. In this research, it has been explored the utilization of high-performance polymer materials, such as Polyetherketoneketone (PEKK), Polyethylene Terephthalate Glycol (PET-G) and MED 857 (DraftWhite), in the designing and developing of customized robotic grippers. The primary focus of made analyses was oriented on materials characterization, both experimentally and analytically. Computer-Aided Engineering (CAE) methods were employed to simulate bending experiments, allowing for a comprehensive analysis of the mechanical behavior of the selected materials. These simulations were validated through physical bending experiments using samples fabricated via 3D printing technologies, including Fused Filament Fabrication (FFF) for PET-G and PEKK, as well as Jetted Photopolymer (PolyJet) technology employing UV Resin for MED 857. The findings of this research provided advantages of utilizing advanced materials like PEKK in low-cost robotic grippers for biomechatronic applications. The experimental and analytical approaches offer valuable insights into material selection, design optimization, and the development of cost-effective high-performing robotic systems with a wide range of applications in the field of biomechatronics.

This paper presents the outcomes of investigations conducted on the development procedure of a personalized prosthetic device for an adult patient. The individualization is achieved through 3D scanning, followed by semi-automated design using the AutoMedPrint system, and low-cost fused deposition modelling (FDM) technology for 3D printing. The prosthesis is aimed for use during bicycle riding and other sport activities. During the conducted experiments outlined in this manuscript, the prosthesis is equipped with force and movement sensors. The purpose is to collect data on its functionality across different scenarios and dynamic activities, aiming to assess potential harm, refine the design, and serve as an initial step before activating the prosthesis end effector. This article describes the methodology in detail, including the process of designing, producing, and programming, as well as laboratory and field test results (including testing performed with and without a patient). Overall, the design and prototype are implemented successfully. A discussion about the need for particular improvements in both the mechanical and electrical areas is finally presented.

This study investigated the relationship between the parameters of the DLP manufacturing process and the structure of photopolymerizable acrylic resins. Four different process parameters were established to produce different thin-walled acrylic sample series: exposure time, layer thickness, area offset, and number of transition layers. The structure and the surface of the obtained samples were examined with the use of the FTIR–ATR method and an optical microscope, respectively. It was proved that extension of the exposure time increases the density of crosslinking and sample thickness. A decreasing crosslinking density due to rising layer thickness is observed. The area offset affects only the dimensions of the sample, predictably reducing the dimensions of the sample as the compensation increases. The absence of transition layers proved unfavorable in many respects, both structurally and geometrically.

The aim of this research was to determine the possibility of applying alternative techniques for the production of prototypes for spare parts in agriculture and to determine the possible directions of development of their applications in the engineering industry. Then, to determine which spare parts could be produced using the FDM technique, comparisons of the most important parameters of spare parts produced independently (using the FDM technique) and obtained from producers (produced using traditional methods in professional factories) were made. A number of factors were analysed, from technical parameters such as machine type, processed material and its consumption including required as support structures, to economic issues such as manufacturing or purchase delivery total time and cost. The FDM technique has proven itself in many ways in the production of spare parts for agricultural machinery.

The necessity for undertaking this research is driven by the prevailing challenges encountered in logistic centers. This study addresses a logistic order-picking issue involving unidirectional conveyors and buffers, which are assigned to racks and pickers with the objective of minimizing the makespan. Subsequently, two variations of a two-step matheuristic approach are proposed as solution methodologies. These matheuristics entail decomposing the primary order-picking problem into two subproblems. In the initial step, the problem of minimizing the free time for pickers/buffers is solved, followed by an investigation into minimizing order picking makespan. An experimentation phase is carried out across three versions of a distribution center layout, wherein one or more pickers are allocated to one or more buffers, spanning 120 test instances. The research findings indicate that employing a mathematical programming-based technique holds promise for yielding solutions within reasonable computational timeframes, particularly when distributing products to consumers with limited product variety within the order. Furthermore, the proposed technique offers the advantages of expediency and simplicity, rendering it suitable for adoption in the process of designing and selecting order-picking systems.

Materials based on photocurable resins and pharmaceutically active agents (APIs) are gaining interest as a composite drug delivery system. In this study, a composite of caffeine with acrylic resin was obtained using an additive manufacturing method of digital light processing (DLP) as a potential material for transdermal drug delivery. The mechanical properties of the composites and the ability to release caffeine from the resin volume in an aqueous environment were investigated. The amount of caffeine in the resulting samples before and after release was evaluated using a gravimetric method. The global thresholding method was also evaluated for its applicability in examining caffeine release from the composite. It was shown that as the caffeine content increased, the strength properties worsened and the ability to release the drug from the composite increased, which was caused by negligible interfacial interactions between the hydrophilic filler and the hydrophobic matrix. The global thresholding method resulted in similar caffeine release rate values compared to the gravimetric method but only for samples in which the caffeine was mainly located near the sample surface. The distribution of caffeine throughout the sample volume made it impossible to assess the caffeine content of the sample using global thresholding.

The paper presents the results of research on the influence of the parameters of Fused Deposition Modelling (FDM) on the mechanical properties and geometric accuracy of angle-shaped parts. The samples were manufactured from acrylonitrile butadiene styrene (ABS) on a universal machine. A complete factorial experiment was conducted. The results indicated that the critical technological parameter was the angular orientation of the sample in the working chamber of the machine. The results were compared with the results of research performed on simple rectangular samples. A significant similarity was found in the relationships between the FDM parameters and properties for both sample types.

A new approach to product quality assessment taken by manufacturers integrates environmental aspects. Design for the environment, also referred to as ecodesign or sustainable design, is an innovative approach to the traditional design process. It focuses on compliance with ecological standards at an early stage of design in CAD 3D environment. In this paper, main objectives of the ecodesign process automation method based on a CAD 3D system are presented. The ecodesign process of a small household appliance is analyzed. The main features of a dedicated software application with a graphical interface, which runs independently of the CAD 3D system, are presented.

The paper presents an application of additive method of Fused Deposition Modeling for manufacturing of small series of elastic models. Additive FDM technology is used to produce a casting mould for multiple use. Process of manufacturing of small series of products consists in casting a two-component silicone rubber degassed using vacuum chamber into a multiple use mould. The paper shows the course of the process and related problems on the example of industrial product – a cylindrical seal. The casting mould was produced out of ABS material using BST 1200 machine, whereas casted elastic models were made out of XTX 45 silicone rubber.

Choosing right Rapid Prototyping technology is not easy, especially for companies inexperienced with that group of manufacturing techniques. Paper summarizes research focused on creating an algorithm for expert system, helping to choose optimal process and determine its parameters for thin-walled products rapid manufacturing. Research was based upon trial manufacturing of different thin-walled items using various RP technologies. Products were categorized, each category was defined by a set of requirements. Basing on research outcome, main algorithm has been created. Next step was developing detailed algorithms for optimizing particular methods. Implementation of these algorithms brings huge benefit for recipients, including cost reduction, supply time decrease and improvements in information flow.