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The possibility of using yarns of biodegradable polyester raw materials creates a new area of research works in knitted fabric technology. Because of the raw material characteristics and different properties of non-woven biodegradable materials, the knitted fabrics under investigation constitute a new generation of technological solutions. The research results presented above concern technological solutions for knitwear and dressing products made of a new generation of multifilament yarns of polylactide (PLA) and poly(glycolide-colactide) (PGLA). Due to the technological works a knitting technique was applied for the construction of the fabrics. Structural solutions for the fabrics were developed for medical dressings and hygienic dressing bands. The materials have biodegradable properties confirmed experimentally. The chemical purity of the materials was determined on the basis of medical product criteria. [ABSTRACT FROM AUTHOR]

Over 3% of the entire Polish population migrate for a job within the European Union, most are aged 18-44 years. The main destinations are Germany, the United Kingdom and Ireland. Immigration is connected with the use of many public services, including healthcare services. Assuming Polish immigrants require medical consultations in the countries they reside in, the authors have analysed the reasons for patients' visits to general practitioners (GPs) in Poland in order to predict possible reasons why Polish patients living abroad may make appointments with GPs in other countries. Data from 22 769 visits to GP practices between June 2005 and May 2006 by Polish patients aged 18-44 years were collected electronically. Age was categorised into three groups (18-24, 25-34 and 35-44 years) and the reason for the visit was categorised according to the ICD 10 coding system. Among the 12 535 patients registered with GPs, 73.1% of women and 68.6% of men required consultations during the year the study was conducted. The highest percentage of visits was recorded for women aged 35-44 years, while men of the same age were the least likely to visit a GP. The mean number of visits per patient ranged from 1.89 for men aged 25-34 years to 3.11 for women aged 35-44 years. The means were similar for 18- to 24-year-old men and women. Women aged 35-44 years had a higher mean number of visits compared with women aged 18-24 years, whereas the opposite was true for men. The analysis of reasons for visits within the age groups indicated that the percentage of appointments for respiratory problems and general and unspecified problems dropped by more than half from the 18-24-year-olds to the 35-44-years-olds, while visits for musculosceletal, cardiovascular, and mental and behavioural problems increased by a factor of four. The presented results intend to enable healthcare services meet Polish immigrants' healthcare needs. [ABSTRACT FROM AUTHOR]

This study presents an in-depth molecular and structural characterization of novel biopolyesters developed under the trademark Bluepha ® . The primary aim was to elucidate the relationship between chemical structure, chain architecture, and material properties of these biopolyesters to define their potential applications across various sectors. Proton nuclear magnetic resonance ( 1 H NMR) analysis identified the biopolyesters as poly[( R )-3-hydroxybutyrate- co -( R )-3-hydroxyhexanoate] (PHBH) copolymers, containing 4% and 10% molar content of hydroxyhexanoate (HH) units, respectively. Mass spectrometry analysis of PHBH oligomers, produced via controlled thermal degradation, further confirmed the chemical structure and molecular architecture of the PHBH samples. Additionally, multistage electrospray ionization mass spectrometry (ESI-MS/MS) provided insights into the chemical homogeneity and arrangement of comonomer units within the copolyester chains, revealing a random distribution of hydroxyhexanoate (HH) and hydroxybutyrate (HB) units along the PHBH chains. X-ray diffraction (XRD) patterns demonstrated partial crystallinity in the PHBH samples. The thermal properties, including glass transition temperature ( T g ), melting temperature ( T m ), and melting enthalpy (Δ H m ), were found to be lower in PHBH than in poly( R )-3-hydroxybutyrate (PHB), suggesting a broader application potential for the tested PHBH biopolyesters.

Nowadays, a very important motivation for the development of new functional materials for medical purposes is not only their performance but also whether they are environmentally friendly. In recent years, there has been a growing interest in the possibility of labelling (bio)degradable polymers, in particular those intended for specific applications, especially in the medical sector, and the potential of information storage in such polymers, making it possible, for example, to track the ultimate environmental fate of plastics. This article presents a straightforward green approach that combines both aspects using an oligopeptide, which is an integral part of polymer material, to store binary information in a physical mixture of polymer and oligopeptide. In the proposed procedure the year of production of polymer films made of poly(l-lactide) (PLLA) and a blend of poly(1,4-butylene adipate-co-1,4-butylene terephthalate) and polylactide (PBAT/PLA) were encoded as the sequence of the appropriate amino acids in the oligopeptide (PEP) added to these polymers. The decoding of the recorded information was carried out using mass spectrometry technique as a new method of decoding, which enabled the successful retrieval and reading of the stored information. Furthermore, the properties of labelled (bio)degradable polymer films and stability during biodegradation of PLLA/PEP film under industrial composting conditions have been investigated. The labelled films exhibited good oligopeptide stability, allowing the recorded information to be retrieved from a green polymer/oligopeptide system before and after biodegradation. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay) study of the PLLA and PLLA/PBAT using the MRC-5 mammalian fibroblasts was presented for the first time., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Delivery systems for biologically active substances such as proanthocyanidins (PCANs), produced in the form of electrospun nonwoven through the electrospinning method, were designed using a polymeric blend of poly(L-lactide-co-glycolide) (PLGA)and poly[(R,S)-3-hydroxybutyrate] ((R,S)-PHB). The studies involved the structural and thermal characteristics of the developed electrospun three-dimensional fibre matrices unloaded and loaded with PCANs. In the next step, the hydrolytic degradation tests of these systems were performed. The release profile of PCANs from the electrospun nonwoven was determined with the aid of UV-VIS spectroscopy. Approximately 30% of the PCANs were released from the tested electrospun nonwoven during the initial 15-20 days of incubation. The chemical structure of water-soluble oligomers that were formed after the hydrolytic degradation of the developed delivery system was identified through electrospray ionization mass spectrometry. Oligomers of lactic acid and OLAGA oligocopolyester, as well as oligo-3-hydroxybutyrate terminated with hydroxyl and carboxyl end groups, were recognized as degradation products released into the water during the incubation time. It was also demonstrated that variations in the degradation rate of individual mat components influenced the degradation pattern and the number of formed oligomers. The obtained results suggest that the incorporation of proanthocyanidins into the system slowed down the hydrolytic degradation process of the poly(L-lactide- co -glycolide)/poly[(R,S)-3-hydroxybutyrate] three-dimensional fibre matrix. In addition, in vitro cytotoxicity and antimicrobial studies advocate the use of PCANs for biomedical applications with promising antimicrobial activity.

This study developed a technical task associated with the formation of welded joints based on biodegradable polymers and their subsequent physicochemical characterization. The primary objective was to establish the effect of the welding process and modification of natural poly(3-hydroxybutyrate) (PHB) with N,N-dibutylundecenoylamide (DBUA) as a plasticizing agent on the structure and properties of PHB-based biopolymer materials as well as the process and structure of welded joints formation using ultrasonic welding technique. The weldability of biodegradable layers based on PHB and PHB/DBUA mixture was ultrasonically welded and optimized using a standard Branson press-type installation. The effect of the DBUA plasticizer and welding process on the structure of PHB-based biodegradable material was investigated using scanning electron microscopy, X-ray diffraction, FT-IR spectroscopy, differential scanning calorimetry, and thermomechanical analysis. The results confirmed that the DBUA acted as an effective plasticizer of PHB, contributing to lower crystallinity of the PHB/DBUA mixture (63%) in relation to the crystallinity degree of pure PHB film (69%). Ultrasonic welding resulted in an additional increase (approximately 8.5%) in the degree of crystallinity in the PHB/DBUA in relation to the initial PHB/DBUA mixture. The significant shift toward lower temperatures of the crystallization and melting peaks of PHB modified with DBUA were observed using DSC concerning pure PHB. The melt crystallization process of PHB was affected by welding treatment, and a shift toward higher temperature was observed compared with the unwelded PHB/DBUA sample. The butt-welded joints of biodegradable PHB/DBUA materials made using the ultrasonic method tested for tensile strength have damaged the area immediately outside the joining surface.

In recent years, one of the main goals of cartilage tissue engineering has been to find appropriate scaffolds for hyaline cartilage regeneration, which could serve as a matrix for chondrocytes or stem cell cultures. The study presents three types of scaffolds obtained from a blend of polyethersulfone (PES) and polyurethane (PUR) by a combination of wet-phase inversion and salt-leaching methods. The nonwovens made of gelatin and sodium chloride (NaCl) were used as precursors of macropores. Thus, obtained membranes were characterized by a suitable structure. The top layers were perforated, with pores over 20 µm, which allows cells to enter the membrane. The use of a nonwoven made it possible to develop a three-dimensional network of interconnected macropores that is required for cell activity and mobility. Examination of wettability (contact angle, swelling ratio) showed a hydrophilic nature of scaffolds. The mechanical test showed that the scaffolds were suitable for knee joint applications (stress above 10 MPa). Next, the scaffolds underwent a degradation study in simulated body fluid (SBF). Weight loss after four weeks and changes in structure were assessed using scanning electron microscopy (SEM) and MeMoExplorer Software, a program that estimates the size of pores. The porosity measurements after degradation confirmed an increase in pore size, as expected. Hydrolysis was confirmed by Fourier-transform infrared spectroscopy (FT-IR) analysis, where the disappearance of ester bonds at about 1730 cm -1 wavelength is noticeable after degradation. The obtained results showed that the scaffolds meet the requirements for cartilage tissue engineering membranes and should undergo further testing on an animal model.

Presented herein are the results of a novel recycling method for waste Tetra Pak ® packaging materials. The polyethylene (PE-T) component of this packaging material, obtained via a separation process using a "solvents method", was used as a carbon source for the biosynthesis of polyhydroxyalkanoates (PHAs) by the bacterial strain Cupriavidus necator H16. Bacteria were grown for 48-72 h, at 30 °C, in TSB (nitrogen-rich) or BSM (nitrogen-limited) media supplemented with PE-T. Growth was monitored by viable counting. It was demonstrated that C. necator utilised PE-T in both growth media, but was only able to accumulate 40% w/w PHA in TSB supplemented with PE-T. Only 1.5% w/w PHA was accumulated in the TSB control, and no PHA was detected in the BSM control. Extracted biopolymers were characterised by nuclear magnetic resonance (NMR), Fourier-transform infrared (FTIR) spectroscopy, electrospray tandem mass spectrometry (ESI-MS/MS), gel permeation chromatography (GPC), and accelerator mass spectrometry (AMS). The characterisation of PHA by ESI-MS/MS revealed that PHA produced by C. necator in TSB supplemented with PE-T contained 3-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate co-monomeric units. AMS analysis also confirmed the presence of 96.73% modern carbon and 3.27% old carbon in PHA derived from Tetra Pak ® . Thus, this study demonstrates the feasibility of our proposed recycling method for waste Tetra Pak ® packaging materials, alongside its potential for producing value-added PHA, and the ability of 14C analysis in validating this bioconversion process.

Poly( L -lactide) is capable of self-assembly into a nematic mesophase under the influence of temperature and mechanical stresses. Therefore, subsequent poly( L -lactide) films were obtained and characterized, showing nematic liquid crystal properties both before and after degradation. Herein, we present that, by introducing β-cyclodextrin into the polymer matrix, it is possible to obtain a chiral nematic mesophase during pressing, regardless of temperature and time. The obtained poly( L -lactide) films exhibiting liquid crystal properties were subjected to degradation tests and the influence of degradation on these properties was determined. Thermotropic phase behavior was investigated using polarized optical microscopy, X-ray diffraction, and differential scanning calorimetry. The degradation process demonstrated an influence on the liquid crystal properties of pressed polymer films. The colored planar texture of the chiral nematic mesophase, which was not observed prior to degradation in films without the addition of β-cyclodextrin, appeared after incubation in water as a result of the entrapment of degradation products in the polymer matrix. These unusual tailor-made properties, obtained in liquid crystals in (bio)degradable polymers using a simple method, demonstrate the potential for advanced photonic applications.