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Many research studies are directed toward developing safe and efficient collagen-based biomaterials as carriers for drug delivery systems. This article presents a comparative study of the properties of new collagen sponges prepared and characterized by different methods intended for biomedical applications. The structural integrity is one of the main properties for a biomaterial in order for it to be easily removed from the treated area. Thus, the effect of combining a natural polymer such as collagen with an antimicrobial drug such as oxytetracycline or doxycycline and glutaraldehyde as the chemical cross-linking agent influences the cross-linking degree of the material, which is in direct relation to its resistance to collagenase digestion, the drug kinetic release profile, and in vitro biocompatibility. The enzymatic degradation results identified oxytetracycline as the best inhibitor of collagenase when the collagen sponge was cross-linked with 0.5% glutaraldehyde. The drug release kinetics revealed an extended release of the antibiotic for oxytetracycline-loaded collagen sponges compared with doxycycline-loaded collagen sponges. Considering the behavior of differently prepared sponges, the collagen sponge with oxytetracycline and 0.5% glutaraldehyde could represent a viable polymeric support for the prevention/treatment of infections at the application site, favoring tissue regeneration.

Depending on the concentration of the drug and/or the method of administration, drugs could be used in various ways. To take full advantage of the drug beneficial properties in oral medical interventions but also in other types of surgery, like plastic surgery, general surgery, or gynecological surgery, the drug concentration as well as the administration method itself will depend on the wound, type of surgery, and severity of the postoperative pain which can be very different. Generally, the local administration methods are recommended. Piroxicam, a nonsteroidal anti-inflammatory drug (NSAID) of the oxicam class, is generally used to relieve the symptoms of pain and inflammation. Starting from the idea of the special benefit of the interference between collagen-based materials and drug beneficial properties, our work was focused on the synthesis and characterization of new collagen-piroxicam materials. These new collagen-based materials present a good water absorption, and the piroxicam release suggests a biphasic drug release profile whereas the obtained values for the release exponent revealed a complex release mechanism including swelling, diffusion, and erosion.

Nowadays, special importance is given to quality control and food safety. Food quality currently creates significant problems for the industry and implicitly for consumers and society. The effects materialize in economic losses, alterations of the quality and organoleptic properties of the commercial products, and, last but not least, they constitute risk factors for the consumer’s health. In this context, the development of analytical systems for the rapid determination of the sanitary quality of food products by detecting possible pathogenic microorganisms (such as Escherichia coli or Salmonella due to the important digestive disorders that they can cause in many consumers) is of major importance. Using efficient and environmentally friendly detection systems for identification of various pathogens that modify food matrices and turn them into food waste faster will also improve agri-food quality throughout the food chain. This paper reviews the use of metal nanoparticles used to obtain bio nanosensors for the purpose mentioned above. Metallic nanoparticles (Au, Ag, etc.) and their oxides can be synthesized by several methods, such as chemical, physical, physico-chemical, and biological, each bringing advantages and disadvantages in their use for developing nanosensors. In the “green chemistry” approach, a particular importance is given to the metal nanoparticles obtained by phytosynthesis. This method can lead to the development of good quality nanoparticles, at the same time being able to use secondary metabolites from vegetal wastes, as such providing a circular economy character. Considering these aspects, the use of phytosynthesized nanoparticles in other biosensing applications is also presented as a glimpse of their potential, which should be further explored.

The present paper synthesized, characterized, and evaluated the performance of the novel biopolymeric membrane enriched with cellulose acetate and chitosan (CHI)-silver (Ag) ions in order to remove iron ion from the synthetic wastewater using a new electrodialysis system. The prepared membranes were characterized by Fourier Transforms Infrared Spectroscopy-Attenuated Total Reflection (FTIR-ATR), Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DSC), contact angle measurements, microscopy studies, and electrochemical impedance spectroscopy (EIS). The electrodialysis experiments were performed at the different applied voltages (5, 10, and 15 V) for one hour, at room temperature. The treatment rate (TE) of iron ions, current efficiency (IE), and energy consumption (Wc) were calculated. FTIR-ATR spectra evidenced that incorporation of CHI-Ag ions into the polymer mixture led to a polymer-metal ion complex formation within the membrane. The TGA-DSC analysis for the obtained biopolymeric membranes showed excellent thermal stability (>350 °C). The contact angle measurements demonstrated the hydrophobic character of the polymeric membrane and a decrease of it by CHI-Ag adding. The EIS results indicated that the silver ions induced a higher ionic electrical conductivity. The highest value of the iron ions treatment rate (>60%) was obtained for the biopolymeric membrane with CHI-Ag ions at applied voltage of 15 V.

Collagen-based biomaterials are increasingly explored in dentistry for their ability to deliver drugs locally and support healing. In this study, we developed chlortetracycline-loaded collagen sponges aimed at preventing postoperative infections. Five formulations were prepared by lyophilization, each with the same collagen-to-drug ratio but different glutaraldehyde (GA) concentrations: 0%, 0.25%, 0.5%, 0.75%, and 1% (w/w) relative to dry collagen. The sponges were characterized using FT-IR and UV–VIS–NIR spectroscopy, and their swelling capacity, enzymatic stability, and drug release kinetics were evaluated. Antibacterial activity was tested against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. Statistical differences between formulations were assessed using one-way ANOVA followed by Tukey’s post hoc test (p < 0.05). All sponges released the antibiotic rapidly within the first 60 min, followed by a sustained release for up to 10 h. The non-crosslinked sponge showed the highest antimicrobial effect, while the 0.25% GA formulation offered a good balance between stability and bioactivity. While higher cross-linking enhanced structural stability, it progressively reduced antimicrobial efficacy, highlighting a crucial design trade-off. These findings underline the need to fine-tune cross-linking conditions to achieve both durability and strong antimicrobial action in collagen-based drug delivery systems for dental applications.

This study investigated the properties of a novel polymeric membrane based on cellulose acetate, polyethylene glycol/poly(styrene)-b-poly(4-vinylpyridine), and embedded with TiO2 nanoparticles (CA/PEG/PS154-b-P4VP381/TiO2 membrane) obtained by wet-phase inversion method. The TiO2 nanoparticles fabricated by a hydrothermal method were characterized by XRD, SEM, EDX, and UV-Vis analyses to determine the purity, morphology, and optical band gap energy. The prepared polymeric membranes with and without TiO2 nanoparticles (CA/PEG/PS154-b-P4VP381/TiO2 and CA/PEG/PS154-b-P4VP381 membranes) were characterized by FTIR, SEM, EDXS, and TGA to observe the effect of TiO2 nanoparticles added to the polymeric membrane matrix and to analyze the chemical structure, morphology, and thermal stability of the obtained polymeric membranes. The contact angle, SFE, water retention, and porosity were also determined. The results showed that adding the TiO2 nanoparticles into the polymeric membrane (CA/PEG/PS154-b-P4VP381/TiO2) significantly reduced the pore size and the water contact angle, increasing the water retention and the porosity. The lower value of the water contact angle of 15.57 ± 0.45° for the CA/PEG/PS154-b-P4VP381/TiO2 membrane indicates a pronounced hydrophilic character. The investigations performed showed that the CA/PEG/PS154-b-P4VP381/TiO2 membrane presents excellent properties and can be a promising material for water and waste-water treatment through membrane processes (e.g., electrodialysis, ultrafiltration, nanofiltration, reverse osmosis) in the future.

We report in this paper the synthesis and characterization of a new collagen-based material. This material was obtained in a spongy form and was functionalized with an antibiotic, ciprofloxacin. The targeted applications of these kind of materials concern the post-operative prophylaxis. The in vitro tests (antimicrobial, cytotoxic, drug release) showed that sponges with a concentration of 0.75 g of ciprofloxacin per gram of collagen could be beneficial for the desired applications.

This study investigated the properties of a novel polymeric membrane based on cellulose acetate, polyethylene glycol/poly(styrene)-b-poly(4-vinylpyridine), and embedded with TiO[sub.2] nanoparticles (CA/PEG/PS[sub.154]-b-P4VP[sub.381]/TiO[sub.2] membrane) obtained by wet-phase inversion method. The TiO[sub.2] nanoparticles fabricated by a hydrothermal method were characterized by XRD, SEM, EDX, and UV-Vis analyses to determine the purity, morphology, and optical band gap energy. The prepared polymeric membranes with and without TiO[sub.2] nanoparticles (CA/PEG/PS[sub.154]-b-P4VP[sub.381]/TiO[sub.2] and CA/PEG/PS[sub.154]-b-P4VP[sub.381] membranes) were characterized by FTIR, SEM, EDXS, and TGA to observe the effect of TiO[sub.2] nanoparticles added to the polymeric membrane matrix and to analyze the chemical structure, morphology, and thermal stability of the obtained polymeric membranes. The contact angle, SFE, water retention, and porosity were also determined. The results showed that adding the TiO[sub.2] nanoparticles into the polymeric membrane (CA/PEG/PS[sub.154]-b-P4VP[sub.381]/TiO[sub.2]) significantly reduced the pore size and the water contact angle, increasing the water retention and the porosity. The lower value of the water contact angle of 15.57 ± 0.45° for the CA/PEG/PS[sub.154]-b-P4VP[sub.381]/TiO[sub.2] membrane indicates a pronounced hydrophilic character. The investigations performed showed that the CA/PEG/PS[sub.154]-b-P4VP[sub.381]/TiO[sub.2] membrane presents excellent properties and can be a promising material for water and waste-water treatment through membrane processes (e.g., electrodialysis, ultrafiltration, nanofiltration, reverse osmosis) in the future.

In this paper, a new polymeric membrane including polymers (cellulose acetate, polyethylene glycol 400), copolymer poly(4-vinylpyridine)-block-polystyrene, and TiO nanoparticles were synthesized by the phase inversion method. In order to investigate the presence and the influence of the TiO nanoparticles on the membrane matrix, a polymeric membrane without TiO nanoparticles was prepared by the same preparation method. The structure of the polymeric membranes was characterized by several techniques, such as Fourier transform infrared spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and impedance spectroscopy. Also, the water contact angle, water retention, and porosity were determined. The results showed that the TiO nanoparticles were incorporated into the pores and onto the surface of the polymeric membrane, which resulted in a more uniform structure. In addition, these polymeric membranes were tested for the removal of cadmium ions from synthetic waste-water using a laboratory-scale electrochemical separation system with a custom-built setup. The results showed that the polymeric membrane with TiO nanoparticles showed a high cadmium ions removal rate (95.53%), compared to the polymeric membrane without TiO nanoparticles (85.29%), after a 1.5 h electrochemical separation test. The final results indicated that the polymeric membranes prepared with TiO nanoparticles had excellent thermal stability and exhibited the best ionic conductivity. The electrochemical separation system proved that the obtained polymeric membranes effectively remove cadmium from the synthetic waste-water.

In this paper, we present the fabrication and characterization of new chitosan-based membranes while using a new biotechnology for immobilizing alkaline phosphatase (ALP). This technology involved metal ions incorporation to develop new biopolymeric supports. The chemical structure and morphological characteristics of proposed membranes were evaluated by infrared spectroscopy (FT-IR) and the scanning electron microscopy technique (SEM). The inductively coupled plasma mass spectrometry (ICP-MS) evidenced the metal ion release in time. Moreover, the effect of Mg2+ on the enzymatic activity and the antibacterial investigations while using Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria, hemolysis, and biocompatibility behavior were studied. Immobilizing ALP into the chitosan membranes composition followed by the incorporation of Mg2+ led to polymeric supports with enhanced cellular viability when comparing to chitosan-based membranes without Mg2+. The results obtained evidenced promising performance in biomedical applications for the new biopolymeric supports that are based on chitosan, ALP, and metal ions.