The simultaneous adsorption of metal ions on bare and functionalized zero-valent iron nanoparticles (nZVI) from aqueous solution was tested using inductively coupled plasma optical emission ...spectrometry (ICP-OES). The nanomaterials were synthetized using borohydride reduction of iron salt followed by addition of EDTA and pyridine-2,6-dicarboxylic acid (dipicolinic acid, PDCA) in different molar ratios. Functionalized materials were characterized by FT-IR, XRD and SEM-EDS methods. The ligand attachment on the particles was confirmed by FT-IR spectroscopy. The formation of a magnetite and feroxyhyte shell on the core of functionalized nanoparticles was confirmed by the XRD study. Transformation of chain-like structures into clusters of nanospheres with smaller diameter size was observed from SEM study of EDTA-nVZI particles. The average diameter of bare nZVI particles comprised 115 nm, while EDTA functionalization resulted in an average diameter of 22 and 35 nm. The PDCA-nZVI particles obtained with the molar ratio of Fe : PDCA = 1 : 1 retain the chain-like structure with enlargement of the average particle diameter to 267 nm. SEM study of PDCA-nZVI particles that were produced using the ratio Fe : PDCA = 2 : 1 have demonstrated the unique property of elongation into ellipsoidal forms of reduced dimensions (
a
= 61 nm;
b
= 28 nm). The simultaneous metal ion removal from aqueous solution was the most efficient in the case of bare nZVI particles (91-97%). EDTA functionalization was found to be highly selective for Cu and Cr removal (95%), while PDCA functionalization shows selective adsorption of Cu, Cr and V in an aqueous medium (93%). Iron nanoparticles functionalized with PDCA in both of the used ratios showed more efficient metal ion adsorption in the case when smaller ellipsoidal particles were formed.
Surface modification of nZVI particles by EDTA and PDCA leads to the formation of magnetite and feroxyhyte shell. PDCA capping caused the elongation of spheres into ellipsoids. Metals adsorption was more efficient on smaller ellipsoidal particles.
In recent years, the production and application of biochar as a soil amendment produced from pruning residues has gained attention worldwide. Since the effect of grapevine rootstock type on ...grapevine-pruning residues used as feedstock for biochar production had not yet been researched, the present research was performed. Two grapevine rootstocks, different in vigor, were selected, with the hypothesis that they would affect their chemical composition and, consequently, the composition of the produced biochar. In this work, grapevine-pruning residues of the indigenous variety “Istrian Malvasia” (Vitis vinifera L.) grafted on 420A and SO4 rootstocks were analyzed and used for biochar production under three peak temperature programs (400 °C, 500 °C, and 600 °C). Higher pyrolysis temperature decreased yield but increased EC, ash, and TC content, as well as the content of most of the studied elements. On the other hand, grapevine rootstock type affected biochar EC, ash content, and specific surface area. Results showed that a more vigorous rootstock affects the produced biochar qualities by enhancing the above-mentioned properties. The present research showed that biochar produced from grapevine-pruning residues, especially at 500 °C or 600 °C, could be a valuable tool for the valorization of this biomass as a soil amendment.
Electrospun materials are good candidates for the design of tissue regeneration scaffolds as they can simulate the natural surroundings of tissue cells. The study proposes electrospun ...polycaprolactone (PCL)/cefuroxime (CFU) scaffolds for human cell culture and investigates the influence of the antibiotic content on scaffold morphology, thermal and mechanical properties. The increase in the CFU concentration resulted in the reduction of fiber diameter and number of deformations. It also influenced the reduction of scaffold thermal enthalpies and improved scaffold break strength. With regard to cell growth, the scaffolds showed precedence in greater colonization of the HeLa cells. Finally, these scaffolds showed compatibility with standard human cell lines, and thus they can be used for the repair of damaged tissues.
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•Different post-depositional alterations of Roman ceramics from Crikvenica's pottery production were identified.•The effects of seawater, anoxic marine sediments and desalination are ...recognizable by multi-analytical methods.•Multivariate statistics on FT-IR spectra represent a suitable method for a first screening and identification of representative samples of each sub-group.•Ceramics excavated from the site of the workshop (local ceramics) can be used as a reference group for future classification studies of Roman ceramics from the Crikvenica production centre.
Different post-depositional conditions and after-recovery treatments may provoke pronounced physicochemical alterations that can make archaeological ceramics’ classification and comparison difficult even when its provenance is known. The present study describes the differences in the chemical composition verified on sherds of Roman ceramics produced in Crikvenica (NE Adriatic, Croatia). Inductive coupled plasma mass spectrometry (ICP-MS), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), as well as Fourier transform infrared spectroscopy (FT-IR) were applied to characterise the chemical composition and post-depositional alterations in ceramics recovered onshore and underwater. Chemometrical treatment of ICP-MS results of elemental composition and FT-IR absorption bands was performed using univariate and multivariate statistical tools. Principal component analysis (PCA) led to clear distinction of several clusters of examined samples, i.e. samples from the mainland, samples from the sea bottom, and desalinated samples. All sherds that have undergone desalination represent a distinct sub-group by means of changes in the ratio of accumulated chemical elements. It was established that accumulation of Ca, Mg and Na and formation of salts such as FeS, Mg6Al2CO3(OH)16·4(H2O), and CaCO3 reflect post-depositional environments and post-recovery treatments in terms of desalination and specific marine underwater conditions (oxic and anoxic). Our results outlined a pattern of post-depositional alterations that could be applied in upcoming classification studies. Roman ceramics produced in Crikvenica and excavated from the workshop possess attributes of a reference group, revealing that Ho, Ce, La, Lu, Tb, Gd, Eu and Sm are the elements least susceptible to post-depositional alterations.
In the Mediterranean basin, the treatment and disposal of olive mill pomace (OMP) remain a salient environmental issue for the olive oil‐producing industry. This study assesses the effects of ...olive‐processing technology (three‐phase and two‐phase systems) on the potential use of OMP as a soil amendment. Samples from 12 Croatian olive mills were analyzed for their total phenolic content (TPC), residual oil fraction, and elemental concentration. The samples were profiled using Fourier transform infrared spectroscopy (FT‐IR) and structurally characterized using scanning electron microscopy‐energy‐dispersive X‐ray spectroscopy (EDS). Compared to three‐phase samples, two‐phase OMP was more acidic (pH 4.5 vs. 5.0), with a higher TPC (3835 vs. 1576 mg/kg fresh weight), oil content (11.7% vs. 7.5% d.w., where d.w. is dry weight), electrical conductivity (EC, 5.1 vs. 3.0 mS/cm), and levels of calcium (Ca, 1.34 vs. 1.20 g/kg d.w.) and copper (Cu, 10.4 vs. 7.0 mg/kg d.w.). Similar values of carbon/nitrogen (C/N; 61 vs. 72), N (10 vs. 8.1 g/kg d.w.), phosphorus (1040 vs. 691 mg/kg d.w.), and potassium (K, 13.7 vs. 8.1 g/kg d.w.) were observed. The amounts of chromium, copper, nickel, and zinc were below EC limits in both cases. The EDS mapping revealed that Ca was concentrated at sharp‐edged OMP particles while K was evenly distributed, suggesting that pelletized OMP compost is preferable for amending soil to obtain a homogeneous distribution of nutrients. It was also possible to distinguish between OMPs based on oil and lignin absorption bands in their FT‐IR spectra. According to the obtained results, composting is recommended for both types of OMP to produce a safe product for amendment purposes.
Core ideas
The total phenols, residual oil, electrical conductivity , calcium and copper are higher in two‐phase than in three‐phase olive mill pomace (OMP).
The high potassium (K) abundance suggests the use of OMP as a fertilizer for K‐demanding crops.
Fourier transform infrared spectroscopy peaks ascribed to olive oil and lignin can discriminate between olive‐processing technologies.
Scanning electron microscopy revealed olive stone fragments and pulp in the OMP.
Calcium concentrates at the sharp edges of OMP particles, while K is evenly distributed.
Background and Purpose: Ailanthus altissima (Mill.) Swingle (Tree of Heaven) is a highly invasive, widespread, and widely investigated plant species native to the broader area of China. Extrafloral ...nectaries are major components of the A. altissima secretory system, but the knowledge of their morphology and role in the tree's physiology is limited. This research aims to explore the morphology of extrafloral nectaries, compare it to previous findings, and discuss their possible role and function.
Materials and Methods: Extrafloral nectaries on leaves have been monitored through different phases of leaf development, from June to August 2015 and 2022. The nectaries' morphology was investigated using Zeiss Axioscope 5 and BOECO BSZ-405 light microscopes, and FEG QUANTA 250 FEI scanning electron microscope, operating at 7 kV and pressure of 60–100 Pa, without samples pretreatment.
Results: Our investigation revealed the absence of earlier reported pores or ducts on the top of the glands. However, it supports one of the first, systematical investigations of A. altissima extrafloral nectaries conducted in Croatia a century ago, which was until recently forgotten by history. We evaluated our findings against prior theories and assessed the nectaries' potential role and purpose in disposing surplus sugars.
Conclusions: The nectar in A. altissima is not secreted via an opening on the leaves but rather through epidermal tissue tearing.
The study focuses on the fabrication and properties evaluation of dual functional electrospun polycaprolactone scaffolds incorporating antibiotic drug cefuroxime and having custom tailored topography ...for the support of human cells to be used in tissue regeneration. The scaffolds were evaluated in regard to their morphology, total porosity, thermal properties, tensile properties and cells adhesion/growth, thus to define the effect of both drug content and physical architecture on the scaffolds properties. Both the addition of the drug and the scaffolds custom topography resulted in higher total porosity (up to 90%), while the fibers diameter highest reduction was up to 73%. The type of 3 D printed collector influenced scaffolds tensile properties, thus the increase of the tensile strength was due to the change of the central cylinder height in the hexagonal geometry of the collectors. Cells distribution and spreading on the electrospun scaffolds after 72 hours, showed that scaffolds with custom topography have more evenly scattered cells than the ones with random electrospun fibers. The study has demonstrated that both drug concentration and scaffolds target topography influenced the scaffolds properties and both can be optimized depending on scaffolds demands.
Tkivno inženjerstvo dobra je alternativa za razvoj tkiva ili potencijalnih organa iz pacijentova vlastitog staničnog materijala, a kako bi se smanjio problem nedostatka organa za transplantaciju. ...Elektroispredeni materijali su dobri kandidati kod primjene u biomedicini tj. kao nosači za uzgoj tkivnih stanica. Kod regeneracije tkiva mogu dodatno prenositi lijekove kontrolirano prema terapiji. U ovom je radu istraživano kontrolirano otpuštanje antibiotika Cefuroxima (CFU) koji se upotrebljava u terapiji okularnog tkiva. Elektroispredeni su polikaprolaktonski nosači uz dodatak CFU-a u udjelima od 1, 2, 5 i 10 mas %. Uspješna kapsulacija antibiotika potvrđena je pojavom novih karakterističnih pikova u FTIR spektrima elektroispredenih mješavina. Dodatkom antibiotika i povećanjem njegove koncentracije dobivaju se vlakna homogenijeg izgleda s manjim brojem deformacija po duljini vlakna. UV-VIS spektrofotometrijom praćeno je vrijeme otpuštanja antibiotika iz elektroispredenih PCL/CFU nosača. Dobiveno je povećanje apsorbancije antibiotika s vremenom i porastom koncentracije lijeka u nosaču.
Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna .
Tijekom dviju sezona zaštitnih arheoloških istraživanja gradine Brekinjova Kosa nedaleko od Gline, otkriveni su ostaci ranosrednjovjekovnog objekta (vjerojatno crkve) i nekropole s bogatim grobnim ...prilozima. Među nalazima se ističe grob unutar samog objekta (grob 4) koji se prema prilozima svrstava u skupinu najbogatijih ranosrednjovjekovnih grobova istraženih na području moderne hrvatske države. Osim metalnih nalaza evidentiranih u grobovima ističe se i određena količina ranosrednjovjekovne keramike pronađene u površinskim slojevima i zasebnim jamama na lokalitetu, a koja bi mogla pružiti podatke o eventualnom naselju populacije koja se ovdje pokapala. S obzirom na to da je okolica lokaliteta uglavnom arheološki neistražena, ovaj nalaz pruža važne podatke o razdoblju ranog srednjeg vijeka na predmetnom području.
Electrospun Polycaprolactone for Controlled Drug Delivery Govorčin Bajsić, Emi; Zubin Ferri, Tea; Tominac Trcin, Mirna ...
Kemija u industriji; časopis kemičara i tehnologa Jugoslavije,
2019, Volume:
68, Issue:
9-10
Journal Article
Peer reviewed
Tkivno inženjerstvo dobra je alternativa za razvoj tkiva ili potencijalnih organa iz pacijentova vlastitog staničnog materijala, a kako bi se smanjio problem nedostatka organa za transplantaciju. ...Elektroispredeni materijali su dobri kandidati kod primjene u biomedicini tj. kao nosači za uzgoj tkivnih stanica. Kod regeneracije tkiva mogu dodatno prenositi lijekove kontrolirano prema terapiji. U ovom je radu istraživano kontrolirano otpuštanje antibiotika Cefuroxima (CFU) koji se upotrebljava u terapiji okularnog tkiva. Elektroispredeni su polikaprolaktonski nosači uz dodatak CFU-a u udjelima od 1, 2, 5 i 10 mas %. Uspješna kapsulacija antibiotika potvrđena je pojavom novih karakterističnih pikova u FTIR spektrima elektroispredenih mješavina. Dodatkom antibiotika i povećanjem njegove koncentracije dobivaju se vlakna homogenijeg izgleda s manjim brojem deformacija po duljini vlakna. UV-VIS spektrofotometrijom praćeno je vrijeme otpuštanja antibiotika iz elektroispredenih PCL/CFU nosača. Dobiveno je povećanje apsorbancije antibiotika s vremenom i porastom koncentracije lijeka u nosaču.
Tissue engineering is a good alternative for the development of tissue or potential organs from the patient’s own cell material in order to reduce the problem of organ transplant deficiency. Electrospun materials are good candidates for use in biomedicine, as scaffolds for tissue cells culture. Additionally, these scaffolds can provide controlled drug release in tissue regenerative therapies. In this paper, controlled release of antibiotic Cefuroxim (CFU), which is used for ocular tissue therapy, was investigated. The polycaprolactone scaffolds were prepared by electrospinning with the addition of CFU in the amount of 1, 2, 5, and 10 wt %. The successful antibiotic capsulation was confirmed by the new characteristic peaks appearing in the FTIR spectra of the electrospun blends. With the addition of antibiotic and increase in its concentration, fibres with more uniform morphology and less deformations along the fibres length were obtained. The release of antibiotic from PCL scaffolds was determined by UV–VIS spectrophotometer. Obtained was an increase in absorption of antibiotics with time and with increased drug concentration in the scaffolds.
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