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Carbonization and activation of flax fibers for the removal of bromazepam from water
No full textThis study investigates the potential of reusing fibrous textile waste as an affordable and
sustainable raw material for producing carbon adsorbents. Flax fibres were subjected to
carbonization followed by chemical activation using KOH as the activating agent. The resulting
carbon adsorbents were analysed for their morphology and surface characteristics using scanning
electron microscopy and Fourier transform infrared spectroscopy. The thermal treatment converted
the lignocellulosic fibres into carbon material that retained its fibrous structure, while the activation
process increased the amount of surface oxygen groups. The adsorption properties of the adsorbents
were tested by removing bromazepam from an aqueous solution, and the effects of initial pH,
bromazepam concentration, and contact time were investigated. Bromazepam removal was rapid,
with over 90% of the compound removed within the first 20 minutes of adsorption. The adsorption
process followed pseudo-second-order kinetics, and the Freundlich isotherm model best described
the equilibrium. Activation significantly enhanced the maximum adsorption capacity of the flax fibrebased
carbon adsorbents, increasing it from 204.6 to 680.5 μg/g. The results suggest that
carbonization and activation of flax fibres can produce highly efficient adsorbents for the rapid
removal of bromazepam from water
Validation of a GC-MS/MS method for determining 200 pesticides in herbal tea infusions
No full textHerbal tea is one of the most consumed beverages worldwide, often associated with health
benefits due to its medicinal plant content. However, residues of pesticides are frequently detected in
herbal tea samples, raising concerns about their potential transfer into tea infusions and the
associated health risks. Therefore, it is essential to determine the extent of pesticide migration into
the infusion and to apply a reliable analytical method for this purpose. This study presents the
validation of a multi-residue method for the quantification of 200 pesticides in herbal tea infusions.
Sample preparation was performed using the QuEChERS method with dispersive SPE cleanup
optimized for colored matrices. Pesticides were quantified using GC-MS/MS. The method was
validated following the SANTE/11312/2021 guidelines. Matrix-matched calibration was conducted
at five concentration levels (0.01–0.1 mg/kg) with correlation coefficients (R²) ranging from 0.990 to
0.9999. Mean recoveries were within 70–120%, and precision under repeatability and
reproducibility conditions was ≤ 20% RSD. The LOQ for all analyzed pesticides was established at
0.01 mg/kg. The results demonstrate that the method is accurate, precise, and suitable for monitoring
pesticide residues in herbal tea infusions
Ultrasound-Assisted Microextraction for Food Chemical Contaminant Analysis: A Review
No full textUltrasound-assisted microextraction (UAME) has emerged as a powerful and sustainable technique for food chemical contaminant analysis, offering a rapid, efficient, and environmentally friendly alternative to conventional extraction methods. This review provides a comprehensive overview of recent advancements in the application of UAME for the determination of various food chemical contaminants, including pesticide residues, potentially toxic elements, mycotoxins, veterinary drugs, and other chemical contaminants. The fundamental principles of ultrasound-assisted extraction are discussed, with an emphasis on the mechanisms of acoustic cavitation and mass transfer enhancement that enable improved analyte recovery from complex food matrices. Key factors influencing extraction efficiency (solvent selection, ultrasonic frequency and power, extraction time, and sample characteristics) were critically analyzed. Additionally, the integration of UAME with modern analytical platforms, such as LC-MS, GC-MS, and ICP-MS, was explored, highlighting its compatibility with high-throughput and multiresidue detection. Compared with traditional techniques, UAME offers significant benefits, including reduced solvent consumption, shorter extraction times, and improved analytical performance. This review also addresses current limitations and future perspectives, particularly regarding standardization, automation, and application in routine food safety monitoring. Overall, UAME represents a promising direction for more sustainable and efficient food chemical contaminant analysis, aligning with the growing demand for green analytical chemistry approaches
Development and characterization of human placenta based bioinks for 3D bioprinting: toward printable scaffolds for soft tissue engineering
No full textBreast reconstruction after mastectomy illustrates the limitations of current soft tissue repair
strategies, which carry the risk of potential complications, and do not significantly alter the
likelihood of disease recurrence compared to mastectomy alone. More broadly, soft tissue
regeneration requires biomaterials that combine structural support with bioactivity. Human
amniotic membrane (hAM) has been applied in skin, corneal and urogenital repair and exhibits
antitumor, antifibrotic, anti-inflammatory, and immunomodulatory properties. We aimed to
develop a 3D-bioprintable scaffold from hAM homogenate (hAM-h) that preserves these
properties and supports soft tissue engineering, with post-mastectomy breast reconstruction as a
model application.
hAM was isolated from placentas of healthy donors following cesarean sections, homogenized,
and analyzed for cytokine profile, extracellular matrix content, and rheological behavior.
Bioactivity was assessed on adipose-derived mesenchymal stem cells (ATMSCs). Hydrogel
formulations were optimized using alginates of different viscosities and concentrations, varying
extrusion printing and crosslinking parameters. Optimized alginates were then mixed with hAMh
to form printable bioinks for extrusion-based bioprinting. Printed scaffolds were crosslinked with CaCl2, characterized mechanically and for swelling, and tested for ATMSC attachment.
Obtained results showed that hAM-h contained high levels of regenerative growth factors,
collagens I/IV, and MMPs. Samples showed stable negative surface charge (< 30 mV),
heterogeneous particle distribution (~192 nm, PDI > 0.5), and consistent rheological profiles.
hAM-h did not impair ATMSC viability in 2D and supported their attachment on 3D constructs.
Mechanical testing revealed higher compressive resistance and weight retention in high-viscosity
alginate/hAM-h scaffolds compared with low-viscosity formulations.
These findings demonstrate the feasibility of hAM-h/alginate bioinks for engineering stable,
bioactive scaffolds that preserved bioactive properties of hAM-h, highlighting their potential for
soft tissue engineering, with breast reconstruction as a clinically relevant application
Materijal na bazi hidrogela ojačanog vlaknima nanoceluloze za kontrolisano otpuštanje resveratrola
No full textPredmet ovog tehničkog rešenja je razvoj polimernog materijala na bazi hidrogela ojačanog vlaknima nanoceluloze, koji je namenjen za dugoročnu negu osetljive i suve kože i ranu prevenciju nastanka rana. Hidrogel je dizajniran tako da omogućava kontrolisano i produženo otpuštanje resveratrola – prirodne aktivne supstance poznate po izraženim antiinflamatornim, antioksidativnim i proangiogenim svojstvima. Ovakva formulacija doprinosi očuvanju integriteta kože, smanjuje lokalne upale i podstiče obnavljanje mikrocirkulacije, što je ključno za prevenciju komplikacija kod osoba sa visokim rizikom od nastanka oštećenja, kao što je slučaj kod dijabetičara.
Materijal na bazi hidrogela je biokompatibilan kozmetički proizvod za negu i održavanje kože, netoksičan i bezbedan za dugotrajnu primenu, čak i na osetljivoj koži. Hidrogel poseduje sposobnost apsorpcije viška vlage i održavanja optimalne vlažnosti kože, čime se smanjuje rizik od isušivanja, pucanja i razvoja ulceroznih promena [1]. Njegova porozna struktura omogućava ravnomernu difuziju aktivne supstance, dok vlakna nanoceluloze poboljšavaju mehaničku stabilnost i povećavaju sposobnost zadržavanja tečnosti, doprinoseći efikasnijoj primeni na većim površinama kože bez curenja ili odvajanja od podloge. Pored toga, nanoceluloza je potpuno prirodna, ekološki prihvatljiva supstanca koja je sigurna, netoksična i ne izaziva alergijske reakcije [2,3]. Kontrolisano otpuštanje resveratrola omogućava kontinuiranu podršku regeneraciji kože i smanjenje upalnih procesa tokom dužeg vremenskog perioda, čime se poboljšava opšte stanje kože kod dijabetičara i smanjuje mogućnost nastanka hroničnih rana [4]. Zahvaljujući jednostavnom i ekonomičnom postupku pripreme, koji ne zahteva posebne uslove niti dodatno prečišćavanje, materijal je pogodan za skaliranje i potencijalnu industrijsku proizvodnju.
Korišćenjem ovog hidrogela moguće je unaprediti strategije nege kože kod dijabetičara, nudeći im preventivnu barijeru protiv razvoja rana, naročito na područjima koja su izložena pritisku ili trenju (stopala, pete, laktovi). Time se značajno smanjuje rizik od razvoja dijabetičkog stopala, infekcija i hroničnih ulkusa, što je od velikog značaja kako za kvalitet života pacijenata, tako i za smanjenje troškova zdravstvenog sistema.Tehničko rešenje kategorije M82 – Novo tehničko rešenje primenjeno na nacionalnom nivo
Impact of Antimicrobial Composite Coatings on the Performance of 3D-Printed Macroporous Scaffolds for Bone Tissue Engineering
No full textDevelopment of biomaterials that support cell adhesion, mechanical stability, local drug
delivery, and antibacterial protection is essential in bone tissue engineering (BTE). To achieve
antimicrobial effects at the implantation site, strategies such as ion-doping of inorganic
particles or polymer coatings with antibiotics can be used. In bone tissue engineering, patientspecific macroporous scaffolds produced by 3D printing are particularly appealing. This study
aimed to enhance the antimicrobial properties of 3D printed scaffolds through composite
coatings composed of chitosan and mesoporous bioactive glass (MBG) particles doped with
Sr²⁺, Mg²⁺, Cu²⁺, and Zn²⁺ ions. Additionally, the coatings were evaluated as carriers for the
antibiotic ciprofloxacin. Scaffolds based on poly(ethylene glycol) diacrylate (PEGDA),
methacrylic acid, gelatin, and multi-doped MBG were fabricated by mask-stereolithography
and coated with chitosan/MBG/ciprofloxacin coatings. Characterization included compressive
strength testing, scanning electron microscopy (SEM), and antimicrobial activity against
Staphylococcus aureus.
SEM confirmed effective coating, while preserving a connected porous structure with pore sizes
of 500 to 900 µm. Ciprofloxacin-functionalized scaffolds exhibited strong antibacterial and
antibiofilm activity, while MBG-containing coatings contributed both to enhanced compressive
strength and additional antimicrobial effects. These results demonstrate that used coatings on
3D printed scaffolds represent a promising multifunctional system for bone regeneration and
local infection control
Multi-ion-doped mesoporous bioactive glass particles
No full textMesoporous bioactive glass particles (MBGs) enriched with therapeutic
ions serve as versatile materials for various biomedical applications.
They are highly valued for their excellent biocompatibility,
biodegradability, and bioactivity. Moreover, their high specific surface
area allows for the simultaneous delivery of therapeutic ions and drugs
at the implementation site. It is possible to fine-tune their biological
properties by employing a multi-ion doping strategy, incorporating
angiogenic ions like Cu and Mg, osteogenic ions such as Mg and Sr,
and antimicrobial ions like Cu and Zn. Nonetheless, careful regulation
of dopant concentrations is essential to prevent cytotoxic effects,
particularly from Cu and Zn ions. This study aimed to obtain multi-iondoped
MBGs with optimal properties for biomedical application
through a microemulsion-assisted sol-gel synthesis technique. The
morphology, textural properties, and cytocompatibility with mouse
bone marrow-derived stem cells (mBMSCs) were analyzed. As a model
drug, ciprofloxacin was used to assess drug delivery properties, while
antimicrobial properties were tested against Candida albicans and
Staphylococcus aureus. Additionally, multi-ion-doped MBGs were
analyzed as bioactive fillers in 3D-printed polymer-based scaffolds. The
results indicate that the developed multi-ion-doped MBGs were
biocompatible with mBMSCs, can carry drugs, and present promising
particulate fillers for application in 3D-printed biocomposite scaffolds.
This research was funded by the Science Fund of the Republic of Serbia
#GRANT No.7470, HyBioComBone and by Ministry of Science,
Technological Development and Innovations, Republic of Serbia (No.
451-03-65/2024-03/200135)
Antioxidant and techno-functional properties of wheat flour fortified with cocoa bean shells
No full textBiofortification of products with functional ingredients can provide a promising strategy for improving the nutritional properties of products and the health status of consumers. Cocoa bean shell (CBS) is one of the main solid wastes generated during the roasting of cocoa beans in chocolate production. This biomass can be an interesting source of nutrients and bioactive compounds due to its high content of dietary fiber, polyphenols, methylxanthines, proteins, and minerals. The fortification of wheat flour is a direct response to consumers’ willingness to correct inadequate diets. This is particularly relevant as wheat flour increasingly shows limited applicability in nutrition due to the presence of gluten (the prevalence of celiac disease) and its insufficient content of dietary fiber and low-quality proteins due to lysine deficiency. This research aims to determine the contribution of CBS in the production of functional flour-based confectionery products.
In this study, wheat flour was fortified with 5%, 10%, and 20% CBS. This composite flour was analyzed using a Mixolab device, where a simulation and comparison of all phases in dough production were conducted for different cocoa bean shell contents in wheat flour. The antioxidant activity (by DPPH Radical Scavenging Activity) and polyphenol content (by the Folin-Ciocalteau method) of the composite flour were analyzed and compared with the values of wheat flour.
The addition of 5% cocoa bean shells to wheat flour increases water absorption, which also contributes to
improved dough stability. When 20% cocoa bean shell is added to wheat flour, the dough requires more time for water absorption, but its rheological properties remain unchanged. With the increase in the proportion of CBS in flour, the antioxidant activity and polyphenol content (from 6.55 to 9.31 mg/g) also increase, which is important for the development of new functional products enriched with CBS.
The analysis results indicate a favorable impact of CBS on the quality of flour-based confectionery products, representing a significant step towards the development of functional products
Enhancing Bone Regeneration: Macro-porous Metallic Scaffolds Functionalized with SHED-Derived EVs
No full textThe repair of large bone defects remains a significant challenge in regenerative medicine. While
metallic scaffolds provide excellent mechanical stability, they often lack the osteoinductivity required
for effective bone regeneration. In this study, we investigated the osteogenic potential of a 3D-printed
Ti6Al4V scaffold functionalized with ceramic coatings and extracellular vesicles (EVs) derived from
stem cells of human exfoliated deciduous teeth (SHED cells) embedded in a collagen hydrogel.
Ti6Al4V scaffolds were coated with graded silicate glasses and hydroxyapatite (HAP) powder doped
with silver. The coatings exhibited strong antibacterial activity, with over 98% reduction in S. aureus
and E. coli cell numbers. Cytocompatibility tests on SHED cells demonstrated a higher metabolic rate
of SHED cells on coated scaffolds compared to uncoated Ti surfaces, while apoptosis/necrosis rates
remained below 5% across all samples. SHED cells seeded directly on coated scaffolds exhibited
improved attachment and proliferation compared to those on uncoated surfaces. These results
indicate that the coated scaffolds combine both strong antibacterial properties and high
cytocompatibility.
To introduce osteoinductive properties, EVs were extracted from SHED-conditioned media via
differential ultracentrifugation. Characterization of the isolated EVs confirmed the presence of
tetraspanin markers CD9, CD63, and CD81 using direct stochastic optical reconstruction microscopy
(dSTORM), while their morphology and size distribution were verified by transmission electron
microscopy (TEM) and nanoparticle tracking analysis (NTA). To ensure controlled release within the
microporous scaffold, EVs were encapsulated in a 0.4% collagen hydrogel. Fluorescence-based NTA
analysis demonstrated that approximately 50% of EVs were gradually released within the first three
weeks. The osteogenic potential of EV-loaded scaffolds was assessed by qRT-PCR analysis of SHED cells
cultured on the material. After 10 days of treatment, significant upregulation of RUNX-2 and BMP-2
gene expression indicated the pro-osteogenic effects of the SHED-EV-enriched scaffold.
These findings suggest integrating SHED-derived EVs within a functionalized Ti scaffold is a promising
strategy for enhancing bone regeneration in large defects
High-performance crystalline nanocellulose (CNC) supercapacitor separator: Achieved by maximizing alkali-induced gel stress-response prior to aerogel compression forming
No full textThis study presents the design and fabrication of high-performance separators for supercapacitors based on a novel finding relating to the structural response between alkali ions and cellulose nanocrystals (CNC). Unlike prior art, the CNC-to-ion ratio was specifically chosen following an observed bimodal rheological stress response to applied strain. The stress maximum passed at higher ion concentration was taken to indicate an optimally permeable cellulose cage-structure development, verified by microscopic imaging of the resultant freeze-dried aerogel. The compressed dried structure demonstrates excellent overall performance, including high average nano hardness (∼122 MPa) and ionic conductivity (∼103.5 mS cm−1) after rewetting at 80 w/w% solids content, outperforming commercial borosilicate glass microfiber separator. Benefiting from its hydrophilicity and high porosity, the rehydrated separator demonstrated efficient potassium ion transport. Integrated into symmetric supercapacitor devices with glucose-derived mesoporous carbon electrodes (∼850 m2 g−1), the device delivers high specific capacitance (∼80 F g−1 at 10 mV s−1), high energy density (2.7 Wh kg−1 at 98.2 W kg−1), and approximately 95 % capacitance retention after 1000 cycles. These findings suggest that prior rheological identification of optimal structuration during ion addition to CNC in aqueous suspension greatly enhances the suitability of these innovative materials for renewable energy storage applications