Çağlar Sivri

Long-duration space missions impair oral drug bioavailability due to gastrointestinal dysfunction and expose formulations to cumulative ionizing radiation (0.5–1000+ Gy). Here, a poly(vinyl alcohol) (PVA)-based orodispersible nanostrip (ODNS) containing vitamin C, Spirulina platensis, and Lamium galeobdolon extract was developed for ultrafast buccal delivery. Electrospun nanofibers were evaluated unirradiated, after low-dose X-ray (100 mGy), and after high-dose gamma (1000 Gy). FTIR confirmed physical hydrogen bonding of all bioactives without covalent degradation, even at 1000 Gy. Surprisingly, gamma-irradiated quaternary formulations (F8) exhibited 156.7% elongation at break despite severe morphological collapse (FEGSEM), surpassing pure PVA (124.5%) and unirradiated F4 (90.5%). This unprecedented ductility is attributed to radiation-induced cross-linking (DSC: crystallinity increased from 29.0% to 31.4%, *p* < 0.05), creating a deformable molecular network. Spirulina-containing formulations showed superior radiotolerance, preserving fibrous architecture below 1000 Gy via phycocyanin-mediated ROS scavenging. Release kinetics were composition-dependent and biphasic: optimal formulation (F12, 100 mGy) achieved 44% release in 1 min, 83% in 3 min, and 95% in 5 min, meeting emergency feeding targets. TGA revealed increased char residue (17.6% at 800°C) due to bioactive thermal barrier effects. This work presents the first radiation-resistant nanostrip platform for direct intraoral absorption, bypassing gastrointestinal limitations for astronaut health in deep space missions.

Yeşil kimya, tehlikeli kirleticilerin oluşumunu en aza indiren veya tamamen durduran kimyasal ürünler ve süreçler geliştirme olanağı sunmaktadır. Bitki bazlı nanopartiküllerin yeşil sentezi, çok yönlülüğü ve uygulama kolaylığı nedeniyle şu anda en çok tercih edilen teknik olarak kabul edilmektedir. Bu çalışma, Olea europea L.'nin sulu ekstresi kullanılarak AgNP'lerin sentezlenmesi ve bu sentezlenen nanopartiküllerle katkılanmış PLA polimerinden elektro eğirme ile nanolif üretimini amaçlamaktadır. Sentezlenen nanopartikülleri karakterize etmek için UV-Vis spektroskopisi, geçirimli elektron mikroskobu (TEM), optik mikroskopi, X-ışını kırınımı (XRD), ve taramalı elektron mikroskobu (SEM) kullanılmıştır. AgNP'lerin etkili sentezi, UV-vis analizi kullanılarak 429 nm'de bir yüzey plazmon rezonans tepe noktasının gözlemlenmesiyle kanıtlanmıştır. TEM analizinde ise, yüzey merkezli kübik yapıya sahip AgNP'lerin ortalama çapı ölçülmüş ve XRD analizi bu ölçümü doğrulamıştır. Sentezlenen AgNP’lerin yüzey merkezli kübik yapıda olduğu XRD analizi ile ortaya konulmuş ve ortalama çapı TEM ile 6±4 nm olarak ölçülmüştür. ASTM E 2149'a göre, AgNP'leri içeren Olea europea L. ekstresi E. Coli'ye karşı antibakteriyel aktivite göstermiştir. Ayrıca optik mikroskopi incelemeleri, nanopartikül katkılamasından dolayı nanoliflerin homojenliğinin arttığını göstermiştir. Elektroeğirme ile üretilen nanopartikül katkılı nanoliflerin ortalama boyutu 0,96 ± 0,41 µm olarak ölçülmüştür.

This study focused on the development of wound dressings. Plant active ingredients such as clover, chickweed, chamomile, garlic, liverwort, bitter melon, pine resin, marigold (Calendula officinalis), and St. John's Wort (Hypericum perforatum L.) were reinforced with polyethylene oxide (PEO) and polyvinyl alcohol (PVA) polymers, and nanofiber membranes were produced by electrospinning. As a result of the analyses, FTIR confirmed the presence of polymer and active ingredient functional groups in the composite membranes; softening and shifting were observed in the peaks. In the FEGSEM analysis, a thin and regular nanofiber structure was obtained in the S12 membrane in the range of 150–500 nm. In the tensile test, the tensile strength of the S12 sample was measured as 25.89 MPa, and this strength was associated with the homogeneous distribution and thinning of the fibers. In the mesenchymal stem cell analysis, cell viability was determined as 98%, and cell death was determined as 2% for the S12 membrane at the end of 72 h. The results show that the S12 composite membrane can be used as a biomaterial with ideal properties in wound healing applications.

The COVID-19 pandemic has hugely affected the textile and apparel industry. Besides the negative impact due to supply chain disruptions, drop in demand, liquidity problems, and overstocking, this pandemic was found to be a window of opportunity since it accelerated the ongoing digitalization trends and the use of functional materials in the textile industry. This review paper covers the development of smart and advanced textiles that emerged as a response to the outbreak of SARS-CoV-2. We extensively cover the advancements in developing smart textiles that enable monitoring and sensing through electrospun nanofibers and nanogenerators. Additionally, we focus on improving medical textiles mainly through enhanced antiviral capabilities, which play a crucial role in pandemic prevention, protection, and control. We summarize the challenges that arise from personal protective equipment (PPE) disposal and finally give an overview of new smart textile-based products that emerged in the markets related to the control and spread reduction of SARS-CoV-2.

Unlike the term sound insulation, which means reducing the penetration of noise into other areas, sound absorption means reducing the reflection and energy of the sound on the surface. It has become a highly noticed issue in recent years because the noise in our daily life is increasing day by day, and it causes some health and comfort disorders. In many areas, textiles have been used for acoustics control and noise absorption purposes. The purpose of this work is to determine the most effective media for sound absorption performance and its relation to thermal conductivity from needle-punched nonwoven, meltblown nonwoven and hybrid forms in different arrangements of these fabrics. To provide comparable samples, both needle-punched nonwoven and meltblown nonwoven samples were produced from 100% Polypropylene fibres. According to sound absorption tests, the hybrid-structured sample having a composition similar to the needle-punched nonwoven sample placed at the bottom of our study, while the meltblown nonwoven sample placed as a face layer outperformed the rest of the samples in terms of sound absorption and thermal conductivity. ‘Meltblown only’ samples had remarkably higher sound absorption efficiency than most of the samples, while the ‘needle-punched nonwoven only’ sample had the lowest sound absorption efficiency in all frequencies.

In this study, the comfort properties of water-proof but breathable (water vapour permeable) textile fabrics having the composite structure containing a membrane layer or a coating layer are examined. In the present study, parameters such as ambient conditions, the air gap between body and garment, thickness of materials used in the production of garments and composite structure affecting the comfort properties of the structures mentioned above were examined. After the selection and obtaining the samples; water vapour permeability, air permeability, waterproofness tests were respectively applied and the results were interpreted in a way that producers and related scientists could benefit. The most important results achieved here are that the water vapour permeability decreases as the thickness of the membrane/coating in which the fabrics are coated/laminated increases, the air gap between the body and the garment reduces the water vapour permeability greatly, the membrane character (microporous / non-porous) has different effects on the water vapour permeability in different ambient conditions. These results sound promising for future studies.

Purpose: The purpose of this paper is to determine which criteria should be taken into account while choosing face masks for pandemic times and to what extent their effects are. Design/methodology/approach: Nine face mask alternatives were evaluated based on the assessments of their performance with respect to twelve attributes. Seven experts were asked to evaluate the mask alternatives and the influences among attributes. In gathering expert judgments, spherical fuzzy number-based linguistic terms were utilized in the study to provide a more comprehensive representation domain to them. Findings: According to the results, the most important attributes are found as material type, cost and bacteria–virus protection level. The best face mask is N95, which is followed by respirators and surgical masks. Research limitations/implications: The implication of the research is to evaluate face masks in terms of criteria such as physical, performance, protection and cost to decide on what basis they were selected as a personal protective equipment (PPE) based on expert assessments. This is useful in selection of the right face mask with optimum performance and provides guidance to the general public and profession specific groups for this purpose. The face mask companies might be also benefitted from the implications of the present study in their design and research and development (R&D) operations. Originality/value: The preference ranking of the face mask alternatives has not been studied in detail yet in the literature. Focusing on this issue, the present study provides a comprehensive assessment of the selection criteria of face masks in the pandemic era.