Microwave-assisted synthesis of selected naphthenicand bile acids derivatives, examin their biological activity as well as thermal and chemical stability of selected medicines

Predviđena istraživanja u ovoj doktorskoj disertaciji su usmerena u pravcu iznalaženja novih, efikasnijih i bržih mikrotalasno-stimulisanih metoda hemijskih transformacija koje ne uključuju prisustvo katalizatora i/ili organskih rastvarača. Primenom specijalnih silicijum-karbidnih reakcionih sudova, brzina i preciznost izvođenja mikrotalasno-stimulisanih transformacija prikazana  je kroz stresne studije aktivnih farmaceutskih ingredijenata u SiC  ploči, odnosno HPLC/GC vialima kao reakcionim sudovima. Ispitano je postojanje netermičkih mikrotalasnih efekata i njihov značaj za precizno tumačenje rezultata mikrotalasne sinteze. U drugom delu ove doktorske disertacije izvršena jemikrotalasno-stimulisana sinteza potencijalno biološki aktivnih  supstanci iz prirodnih lako dostupnih materijala kao što su naftenske kiseline. Sintetizovani su amidi i estri individualnih i prirodnih naftenskih kiselina Velebit. U radu je takođe ispitana biološka aktivnost sintetizovanih derivata. Proučavan je uticaj prirodnih naftnih kiselina Velebit injenih derivata na rast pet sojeva  Pseudomonassp., kao i uticaj odabranih sintetisanih jedinjenja na proliferaciju pet  ćelijskih linija humanih tumora pri  čemu je kao kontrola služila jedna zdrava humana ćelijska linija.Scientific research predicted in this PhD thesis isdirected to ascertainment new, efficient and faster microwave-assisted methods of chemical transformations in the absence of catalysts and/or organic solvents. Applaying special silicon-carbide  reaction vessels, speed and accuracy of microwave-assisted transformations are ilustrated within stress testing of active pharmaceutical ingredients in HPLC/GC vials placed in SiC plate. Existence of nonthermal microwave effects and their influence on  accurate interpretation of microwave synthesis results are also investigated.  In the second part of this thesis microwave-assisted synthesis of potentionally biologically active compounds from readily available natural materials, such as  naphthenic acid is accomplished. Amides and esters of individual and natural naphthenic acids Velebitare synthetised. The thesis also examined the biological activity ofthe synthesized products. The effect of natural petroleum acids  Velebitand its derivatives are examined on the growth of five strains of Pseudomonas sp., and the impact of selected synthesized compounds on the proliferation of five human tumor cell lines in which a healthy human cell line is tused as the control

Photocatalytic activity induced by zinc phthalocyanine synthesized by microwave irradiation

Zinc phthalocyanine, synthesized under microwave irradiation proved to be an interesting photocatalyst. The degradation of Rose Bengal, as model organic dye, under visible light irradiation was used to study the adsorption/photocatalytic activity. The huge potential of the synthesized molecule for the removal of organic pollutants was demonstrated by its absorption capacity, which was far larger than that of dye degradation

A fast and efficient synthesis of gamma rays dosimeters based on metalophthalocyanines

The area of radiation protection has gained significant relevance due to the fast advancement of radiation technology and its utilization in scientific research. In order to meet the low doses of nuclear radiation, such as gamma (γ)-rays, development of great fineness, stable, and reliable sensors are required. The heterocyclic compounds known as metallophthalocyanines (MPcs) won considerable research interest owing to their exceptional thermal, chemical and photo-stability, and long wavelength absorption compatible with biological window, spreading their potential applications in technology and medicine. As a result, finding the ideal method for creating such molecules is always in the spotlight. In this work, we designed a novel and efficient microwave-assisted synthetic method for preparation of innovative sensor materials base on MPcs (M = Zn, Mn or Fe). A zinc phthalocyanine has been evaluated as model compound in preparing ZnPc/PVA composites as a new, effective chemical-based dosimeter for low-dose measurement of γrays within the dose range from 1-25 kGy. A microwave-enhanced synthetic approach has been evaluated as an impressive chemical-based dosimeter designer. A modest decrease in absorbance intensity, followed by color bleaching in the dose range of 1-25 kGy, enabled the preparation of ZnPc/PVA composites as fine, glossy surface films with impressive application in gamma-ray dosimetryTwenty-First Young Researchers’ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 29 – December 1, 2023, Belgrade, Serbi

Synthesis of bile acid amines via microwave irradiation

Herein, we present microwave-assisted reductive amination of oxo derivative of deoxycholic acid with morpholine in the presence of sodium-cyanoborohydride. These chemical transformation produces a majority of the 3β-amino isomer 5 as a new compound after five minutes of irradiation. In addition, formylated bile acid have been proved as excellent starting material for the synthesis of bile acid`s N-morpholino amine. Microwave-assisted reactions of formylation in the absence of catalyst, selective deformylation, as well as further oxidation with N-bromosuccinimide gained 3-oxo derivatives of deoxycholic acid acid in high yield. Compared to the conventional protocol a remarkable reduction in overall processing time from hours to a few minutes was achieved

Redefinisanje prostora savremenog konteksta grada - kretanje i percepcija kao vidovi dostupnosti

The aim of this paper is research of the potential and redefining of space of the contemporary urban context, by recognizing movement and senses as principles of accessibility and affirmation of the neglected values of the city in regard to design aspects. A global context of networking transforms a modern city into processes of busy lifestyle, which neglect diversity and senses. Flows and networking, as the carriers of this context, despite their goal to create a connection between the global and the local and establish equality of all users, generate local separation and segregation, eliminating specific local traits and individual needs, thus neglecting individual units of space, social groups and subjects. The consequences of the city developing in this way are spatial fragments not connected to a network and not defined, and on the other hand neglected in a way that leads to specific environmental and sensory values, which under contemporary conditions propagate subjectivity, different impressions and effects. This spatial potential becomes recognized, distinguished and accessible through design methods and principles of inclusive design. The paper uses the methodology of the subject Access to All, a part of the Master studies programme at the Faculty of Architecture, as well as students' research on the topic of inclusion and equal accessibility of the city's potential through projects and design.Cilj rada je istraživanje potencijala i redefinisanje prostora savremenog urbanog konteksta, prepoznajući kretanje i čulnost kao principe dostupnosti i afirmacije zapostavljenih vrednosti grada kroz projektantske aspekte. Globalni kontekst umreženosti savremeni grad transformiše u procese ubrzanog načina života, kojima se zapostavljaju raznovrsnost i čulnost. Tokovi i umrežavanje, kao nosioci takvog konteksta, nasuprot cilju da ostvare vezu globalnog i lokalnog i uspostave jednakost svih korisnika, sa druge strane stvaraju lokalne separacije i segregacije, eliminišući lokalne specifičnosti, pojedinačne potrebe i tako zapostavljajući pojedine prostore, društvene grupe i subjekte. Posledica ovakvog razvoja grada su neumreženi i nedefinisani prostorni fragmenti, čija je zapostavljenost sa druge strane nosilac specifičnih ambijentalnih i čulnih vrednosti, koje u savremenim okolnostima afirmišu subjektivnost, drugačije doživljaje i efekte. Ovi prostorni potencijali postaju prepoznati, naglašeni i dostupni putem projektantskih metoda i principa inkluzivnog dizajna. Rad se oslanja na metodologiju predmeta Dostupnost za sve na programu Master studija Arhitektonskog fakulteta, kao i na studentska istraživanja na temu inkluzije i jednake dostupnosti potencijala grada kroz projektovanje i dizajn

Bioinspired NEMS-Prospective of Collaboration with Nature

The fields of micro- and nanomechanics are strongly interconnected with the development of micro-electro-mechanical (MEMS) and nano-electro-mechanical (NEMS) devices, their fabrication and applications. This article highlights the biomimetic concept of designing new nanodevices for advanced materials and sensing applications

Multiple Roles of LOXL2 in the Progression of Hepatocellular Carcinoma and Its Potential for Therapeutic Targeting

LOXL2, a copper-dependent amine oxidase, has emerged as a promising therapeutic target in hepatocellular carcinoma (HCC). Increased LOXL2 expression in HCC has been linked with an aggressive phenotype and represents a poor prognostic factor. Here, we focus on the mechanisms through which LOXL2 orchestrates multiple oncogenic functions in HCC development. We performed a review of the current knowledge on the roles LOXL2 performs in the modulation of the HCC tumor microenvironment, formation of premetastatic niches, and epithelial–mesenchymal transition. We also highlighted the complex interplay between LOXL2 and hypoxia, angiogenesis, and vasculogenic mimicry in HCC. At the end of the review, we summarize the current LOXL2 inhibitors and discuss their potential in HCC precision treatment

Surface chemistry of "boron" doped carbon quantum dots

Carbon quantum dots (CQDs), are a novel class of carbon nanomaterials that exhibit outstanding physical, chemical, and optical characteristics in addition to strong light absorption. By substituting some of the carbon atoms in CQDs for heteroatoms like N, B, P, and S, it is possible to modify the surface chemistry and electronic properties of the structures, boosting their catalytic activity. Adding B dopant to CQDs changes its surface chemistry and morphology, opening up a wide range of potential uses. The presented study illustrates a quick and environmentally friendly method for producing B-CQDs through microwave-assisted method. According to TEM characterization, the generated B-CQDs had a spherical form, an average diameter of 12 nm, and were negatively charged particles with good water dispersibility and no discernible aggregation. The thorough surface chemistry characterization revealed the presence of B-O and B-C bonds, as well as oxygen-containing surface functional groups in the form of hydroxyl, carbonyl, and carboxyl groups. Additionally, using an RB organic dye as a model molecule, the sonocatalytic, photocatalytic, and synergistic effects of the two processes were investigated

Antioxidant and prooxidant features of N-CQD in photocatalytic testing of aquatic media

The modern age science is still searching for an effective photocatalytic material for the treatment of colored discharges from different industries which cause severe environmental issues. The excellent properties of nitrogen doped carbon quantum dots (N-CQD) enable their successful application as photocatalytic material in organic dye removal triggered under light absorption. With this in mind we first present a successfully performed microwave-assisted synthesis method, a green, simple and economically affordable method for N-CQD synthesis with high nitrogen percentage incorporated in the form of pyrrolic, pyridinic/NH2 and graphitic/NH3 groups. The pro-oxidant and antioxidant features of the synthesized N-CQD were further presented, with high removal efficiency of synthesized N-CQD towards the methylene blue (MB) organic dye, as one of the leading water pollutants with a major risk to aquatic and human life