Manufacturing Process of Prostheses Using Semirigid Molds by Additive Technologies.

Prostheses play a vital role in restoring function and mobility to individuals with physical disabilities. This study focuses on the procedure to create customized prostheses using semirigid molds obtained from additive technologies. This innovative methodology aims to improve the fit and comfort of prostheses.The manufacturing process of prostheses using semirigid molds combined with additive technologies involves several key phases. These include the use of computed tomography (CT) of the affected area, computer-aided design, and the production of custom mold models.This study introduces the main production phases of customized prostheses, based on the strategy that involves the manufacturing of semirigid molds, by additive manufacturing (AM). This approach improves fit, comfort, and integration of prostheses into patients' daily lives. In particular, prostheses for cranioplasty are described in this study.

Correction: Bisighini et al. Fabrication of Compliant and Transparent Hollow Cerebral Vascular Phantoms for In Vitro Studies Using 3D Printing and Spin-Dip Coating. Materials 2023, 16, 166.

In the original publication [...].

Antimicrobial Surface for Devices Used in Stem Culture Manipulation and In Vitro Biofabrication of Tissues.

Cell therapy and engineered tissue creation based on the use of human stem cells involves cell isolation, expansion, and cell growth and differentiation on the scaffolds. Microbial infections dramatically can affect stem cell survival and increase the risk of implant failure. To prevent these events, it is necessary to develop new materials with antibacterial properties for coating scaffold surfaces as well as medical devices, and all other surfaces at high risk of contamination. This chapter describes strategies for obtaining antibacterial blends for coating inert surfaces (polymethylmethacrylate, polycarbonate, Carbon Fiber Reinforced Polymer (CFRP)). In particular, the procedures for preparing antibacterial blends by mixing polymer resins with two types of antibacterial additives and depositing these blends on inert surfaces are described.

Patient-specific cranioplasty, by direct and indirect additive manufacturing of biopolymers and implantable materials.

BACKGROUND: Autologous bones are traditionally used in surgical reconstruction of skullcap. Since patients' bones are often unavailable or cause of infections, implantable synthetic materials emerged as promising alternative. These can be shaped by different technologies, while 3D printing offers remarkable chances in terms of flexibility, accuracy, cost-saving and customizability. METHODS: This study aims to evaluate strengths and limitations of the three main strategies that imply additive manufacturing for the implementation of cranial prosthesis: (i) direct printing of PLA (polylactic acid) skullcaps, mould casting of poly(methyl methacrylate) (PMMA) prosthesis using (ii) silicone mould manufactured from a 3D printed master, (iii) 3Dprinted TPU (thermoplastic polyurethane) mould. RESULTS: All solutions achieved good geometric accuracy and excellent mechanical resistance. Direct printing of the PLA resulted in the fastest strategy, followed by PMMA casting in a silicone mould. CONCLUSIONS: The use of silicone was overall more advantageous, due to lower costs and the possibility of sterilization by using autoclaving.

Fabrication of Compliant and Transparent Hollow Cerebral Vascular Phantoms for In Vitro Studies Using 3D Printing and Spin-Dip Coating.

Endovascular surgery through flow diverters and coils is increasingly used for the minimally invasive treatment of intracranial aneurysms. To study the effectiveness of these devices, in vitro tests are performed in which synthetic vascular phantoms are typically used to reproduce in vivo conditions. In this paper, we propose a manufacturing process to obtain compliant and transparent hollow vessel replicas to assess the mechanical behaviour of endovascular devices and perform flow measurements. The vessel models were obtained in three main steps. First, a mould was 3D-printed in a water-soluble material; two techniques, fusion deposition modelling and stereolithography, were compared for this purpose. Then, the mould was covered with a thin layer of silicone through spin-dip coating, and finally, when the silicone layer solidified, it was dissolved in a hot water bath. The final models were tested in terms of the quality of the final results, the mechanical properties of the silicone, thickness uniformity, and transparency properties. The proposed approach makes it possible to produce models of different sizes and complexity whose transparency and mechanical properties are suitable for in vitro experiments. Its applicability is demonstrated through idealised and patient-specific cases.

Development of a recombinant Fab-fragment based electrochemical immunosensor for deoxynivalenol detection in food samples.

A reliable and cost-effective electrochemical method for the detection of deoxynivalenol (DON) in cereals and cereal-based food samples based on the use of a novel anti-DON Fab fragment is presented. The analytical system employed, Enzyme-Linked-Immunomagnetic-Electrochemical (ELIME) assay, is based on the use of immunomagnetic beads (IMBs) coupled with eight magnetized screen-printed electrodes (8-mScPEs) as electrochemical transducers. Using standard solutions of DON, a working range between 100 and 4500 ng/ml was obtained with an EC(50) of 380 ng/ml. The ELIME assay was employed to evaluate the cross-reactivity of the Fab fragment towards different trichothecenes revealing a good selectivity towards DON over other trichothecenes with the exception of 3-Ac-DON. The sensor was then applied to cereals and cereal-based food samples (wheat, breakfast cereal and baby-food) and a wide range of sample treatment procedures was tested. Within-laboratory precision (9-24% repeatability for breakfast cereals and 10-33% for baby-food) and recovery data (82-110% for breakfast cereals and 97-108% for baby-food) were calculated by analyzing blank breakfast cereals and baby-foods fortified with DON, demonstrating that the proposed method has the capability for use as a screening assay for DON in such products.

ELIME (enzyme linked immuno magnetic electrochemical) method for mycotoxin detection.

Immunoassays are a valid alternative to the more expensive and time consuming quantitative HPLC or GC(1, 2) methods for the screening detection of hazardous mycotoxins in food commodities. In this protocol we show how to fabricate and interrogate an electrochemical competitive Enzyme linked immunomagnetic assay based on the use of magnetic beads as solid support for the immunochemical chain(3) and screen printed electrodes as sensing platform. Our method aims to determine the total amount of HT-2 and T-2 toxins, mycotoxins belonging to the trichothecenes family and of great concern for human health(4). The use of an antibody clone with a cross reactivity of 100% towards HT-2 and T-2 allows to simultaneously detect both toxins with similar sensitivity(5). The first step of our assay is the coating step where we immobilize HT2-KLH conjugate toxin on the surface of magnetic beads. After a blocking step, necessary to avoid non-specific absorptions, the addition of a monoclonal antibody allows the competition between immobilized HT-2 and free HT-2 or T-2 present in the sample or dissolved in a standard solution. At the end of the competition step, the amount of monoclonal antibody linked to the immobilized HT-2 will be inversely proportional to the amount of toxin in the sample solution. A secondary antibody labeled with alkaline phosphatase (AP) is used to reveal the binding between the specific antibody and the immobilized HT-2. The final measurement step is performed by dropping an aliquot of magnetic bead suspension, corresponding to a specific sample/standard solution, on the surface of a screen-printed working electrode; magnetic beads are immobilized and concentrated by means of a magnet placed precisely under the screen-printed electrode. After two minutes of incubation between magnetic beads and a substrate for AP, the enzymatic product is detected by Differential Pulse Voltammetry (DPV) using a portable instrument (PalmSens) also able to initiate automatically eight measurements within an interval of few seconds.