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Comparison of ICP-MS and TXRF techniques for elemental analysis of whey protein
No full textProteini sirutke jedni su od često upotrebljavanih dodataka prehrani te stoga određivanje njihovog mineralnog sastava može biti od velikog interesa za potrošače te od koristi za proizvođače. U mineralnom je sastavu proteina sirutke dokazana prisutnost teških metala. S obzirom na moguće štetne utjecaje na ljudsko zdravlje, korisno je odrediti sadržaj prisutnih teških metala u proteinima sirutke. Glavni cilj ovog eksperimentalnog diplomskog rada bio je odrediti elementarni sastav proteina sirutke dostupnih na tržištu pomoću TXRF i ICP-MS tehnike te usporediti rezultate dobivene dvjema različitim tehnikama. Prikupljeni uzorci pripremljeni su postupkom mikrovalne digestije. U svim uzorcima primjenom obje tehnike određeni elementi su: željezo, bakar, cink, stroncij, rubidij. U svim uzorcima primjenom TXRF tehnike određen je i brom. Drugim spektroskopskim tehnikama brom nije jednostavno odrediti što čini još jednu prednost ove tehnike u usporedbi s ostalim spektroskopskim tehnikama za elementarnu analizu. Analizom rezultata uočene su značajne razlike u sadržaju elemenata u različitim uzorcima proteina sirutke. U svim uzorcima najzastupljeniji element je željezo, a nakon njega većinom slijedi cink zatim bakar ili stroncij. Dobiveni rezultati s obje tehnike u većini slučajeva nisu pokazali statističku značajnu razliku, što potvrđuje da se umjesto standardizirane ICP-MS tehnike kao alternativa u određivanju sadržaja proteina sirutke može koristiti i TXRF. Primjena TXRF tehnike prvenstveno zbog uporabe vrlo male količine uzorka i reagensa, nekorištenja rashladnih sustava i plinova, kvantifikacije pomoću unutarnjeg standarda je jednostavnija, brža te ekonomski i ekološki održivija tehnika u usporedbi s ICP-MS tehnikom. Obećavajući rezultati dobiveni primjenom ove tehnike za određivanje sadržaja teških metala u proteinima sirutke otkrivaju veliki potencijal ovog uređaja za brzu i jednostavnu analizu različitih tipova uzoraka.Whey proteins are among the most commonly used dietary supplements, so determining their mineral composition can be of great interest to consumers and benefit to manufacturers. The presence of heavy metals has been detected in the mineral composition of whey proteins. Considering the possible harmful effects on human health, it is useful to determine the concentration of heavy metals present. The main objective of this experimental work was to determine the elemental composition of whey proteins available on the market using the TXRF and ICP-MS techniques and to compare the results obtained with the two different techniques. The following elements were determined in all samples using both techniques: Iron, Copper, Zinc, Strontium, Rubidium. Bromine was also determined in all samples using the TXRF technique. Bromine is difficult to determine using other spectroscopic techniques, which represents a further advantage of this technique over other spectroscopic techniques for elemental analysis. The analysis of the results showed considerable differences in the element content of the different whey protein samples. Iron was the most abundant element in all samples, followed by zinc, copper and strontium. The results obtained with both techniques showed no statistically significant difference in most cases, confirming that the TXRF technique can be used as an alternative to the standardised ICP-MS technique for the determination of whey protein content Compared to the ICP-MS technique, the TXRF technique is simpler, faster, more economical and more environmentally friendly, as only a very small amount of samples and reagents are required, no cooling systems or gases are used and quantification is performed with an internal standard. The promising results obtained with this technique in the determination of heavy metal content in whey proteins show the great potential of this device for fast and easy analysis of different types of samples
The effect of botulinum toxin type a on neural activation in the region of the trigeminal caudal nucleus in a model of inflammatory pain induced by formalin
No full textBol kroničnog trajanja je veliki problem u svijetu i u mnogim se slučajevima ona ne može uspješno kontrolirati konvencionalnim analgeticima. Tijekom posljednja tri desetljeća u nekliničkim i kliničkim istraživanjima pokazan je potencijal botulinum toksina tipa A (BT-A) u nanogramskim dozama u smanjenju i dugotrajnoj kontroli kronične boli različite etiologije. Međutim, njegov mehanizam djelovanja na patološku bolnu preosjetljivost nije do kraja poznat. Dosadašnja istraživanja pokazala su da BT-A s perifernog mjesta primjene retroaksonalnim transportom putuje u središnji živčani sustav gdje modulira djelovanje različitih neurotransmiterskih sustava, da bi najnovija istraživanja sugerirala i njegov među-sinaptički prijenos. U ovom diplomskom radu je istraženo središnje antinociceptivno djelovanje periferno jednostrano primjenjenog BT-A u modelu upalne boli izazvane bilatralnom primjenom formalina u području njuške štakora. Praćenjem ekspresije c-Fos-a pokazano da BT-A smanjuje neuralnu aktivaciju u neuronima TNC-a na strani na kojoj je primjenjen, ali i na suprotnoj strani, pri čemu neutralizirajući antitoksin za BT-A poništava to djelovanje na obje strane. Rezultati ovog rada se slažu s do sada provedenim istraživanjima i upućuju na među-sinaptički prijenos kao važan čimbenik u kompleksnom mehanizmu antinociceptivnog djelovanja BT-A.Chronic pain is big health-care issue worldwide, and in many cases, it cannot be completely resolved with conventional analgetics. Over the past three decades, non-clinical and clinical research demonstrated that in nanogram concentrations, botulinum toxin type A (BT-A) has potential to alleviate and long-term control chronic pain of various etiologies. However, its mechanism of action on pathological pain hypersensitivity is not fully understood. So far, researchers have shown that BT-A travels from peripheral application site to central nervous system via retrograde axonal transport, where it modulates different neurotransmitter systems, and the latest research suggests transynaptic transmission. In this master’s thesis, the central antinocieptive action of unilaterally, peripherally applied BT-A, was investigated in the inflammatory pain model caused by bilateral application of formalin to the rat whisker pad. By monitoring expression of c-Fos as a marker of neural activation, it was shown that BT-A reduces neural activation in the neurons of the TNC region on the side of the application as well as on the opposite side, whilst neutralizing BT-A antitoxin reverses BT-A effect on both sides. Obtained results in this master’s thesis are consistent with previous studies and indicate that transynaptic transmission is one of the important factors in the complex antinociceptive mechanism of BT-A
Novel 1,2,3-triazole derivatives of benzoxazole and benzimidazole: synthesis and structural characterization
No full textU ovom radu opisana je sinteza novih 1,2,3-triazolnih derivata benzoksazola i benzimidazola klik-reakcijom, njihova strukturna karakterizacija spektroskopijom NMR te analiza in silico. Reakcijom ciklokondenzacije odgovarajućih aminofenola pripravljeni su derivati benzo[d]oksazol-2-tiola 2 i 3 koji su reakcijom kondenzacije s 2-(klormetil)-1H-benzo[d]imidazolom 1 prevedeni u hibride benzimidazola i benzoksazola 4 i 5 premoštene tiometilenskom spojnicom. Reakcijom N-propargiliranja dobivenih hibrida pripravljeni su alkilirani derivati 7 i 8 koji su 1,3-dipolarnom cikloadicijom kataliziranom bakrom s prethodno pripravljenim azidima 9–16 prevedeni u ciljane 1,2,3-triazolne derivate benzimidazola i benzoksazola 18–31. Strukturna karakterizacija sintetiziranih spojeva provedena je spektroskopijom 1H- i 13C-NMR, dok su biološka djelovanja predviđena PASS analizom in silico.This paper describes the synthesis of novel 1,2,3-triazole derivatives of benzoxazole and benzimidazole by click reaction, their structural characterization using NMR spectroscopy and in silico analysis. Derivatives of benzo[d]oxazole-2-thiol 2 and 3 were prepared through cyclization of appropriate aminophenols, followed by condensation with 2-(chloromethyl)-1H-benzo[d]imidazole 1 to obtain hybrids of benzimidazole and benzoxazole 4 and 5 bridged by a thiomethylene linker. N-propargylation reaction of the resulting hybrids yielded alkylated derivatives 7 and 8, which underwent copper catalyzed 1,3-dipolar cycloaddition with prepared azides 9–16 to yield targeted 1,2,3-triazole derivatives of benzimidazole and benzoxazole 18–31. Structural characterization of novel compounds was carried out by 1H- and 13C-NMR spectroscopy, while biological activity was predicted by in silico PASS analysis
Validation of SPE-HPLC-MS/MS method for simultaneous analysis of palbociclib and fulvestrant in human plasma
No full textRak dojke najčešća je zloćudna bolest žena u razvijenom svijetu. Najčešći tip raka dojke je
HR+/HER2-. Razvoj rezistencije tumora na starije lijekove doveo je do potrebe za razvojem novih
lijekova, kao što su inhibitori kinaza ovisnih o ciklinima. Ovi lijekovi primjenjuju se uvijek u
kombinaciji s inhibitorima aromataze ili fulvestrantom. Bioanalitičkim metodama za terapijsko
praćenje lijekova u krvi omogućuje se precizno i individualno doziranje lijekova, potrebno zbog
razlika u farmakokinetici i uskoj terapijskoj širini lijeka. Sukladno ICHM10 smjernicama, u ovom
radu validirana je nova bioanalitička metoda za određivanje lijekova palbocikliba i fulvestranta,
izražavanjem linearnosti, točnosti, preciznosti, ekstrakcijskog prinosa i utjecaja matrice. Korištena
je tehnika ekstrakcije čvrstom fazom kojom su analiti izolirani iz plazme zdravih dobrovoljaca.
Analiza je provedena tekućinskom kromatografijom spregnutom sa spektrometrom masa s
analizatorom trostrukog kvadrupola. Metoda je validirana u koncentracijskim rasponima 30 - 300
ng/mL za palbociklib i 10 - 100 ng/mL za fulvestrant. Unutar koncentracijskih raspona dokazana je
linearnost (R > 0,9993) preciznost (RSD < 1,85) i točnost (raspon točnosti od -10,42 % do -3,92 %).
Ekstrakcijski prinos za palbociklib veći je od 91,17 %, dok je za fulvestrant veći od 77,52 %. Utjecaj
matrice za PAL je 10,25 % i 6,92 %, pri nižoj i višoj izmjerenoj koncentraciji, a za FUL iznosi -
11,99 % i -9,23 %. Naposlijetku su određene koncentracije palbocikliba i fulvestranta u uzorcima
plazme stvarnih pacijentica, čime je pokazana primjenjivost metode u terapijskom praćenju ovih
lijekova.Breast cancer is the most common malignant disease in women of the developed world. The most
common type of breast cancer is HR+/HER2-. The development of tumor resistance to older drugs
has led to the need to develop new ones, such as cyclin-dependent kinase inhibitors. These drugs are
always used in combination with aromatase inhibitors or fulvestrant. Bioanalytical methods for
therapeutic drug monitoring enable precise and individual drug dosing, necessary due to differences
in pharmacokinetics and a narrow therapeutic window of the drug. Following the ICHM10
guidelines, in this work a new bioanalytical method for detection of palbociclib and fulvestrant was
validated, expressing linearity, accuracy, precision, recovery and matrix effect. Solid-phase
extraction technique was used to isolate analytes from the plasma of healthy volunteers. The analysis
was performed by liquid chromatography coupled to a mass spectrometer with a triple quadrupole
analyzer. The method was validated in the concentration ranges of 30 - 300 ng/mL for palbociclib
and 10 - 100 ng/mL for fulvestrant. Linearity (R > 0.9993), precision (RSD < 1.85) and accuracy
(accuracy range from -10.42% to -3.92%) were demonstrated within the concentration range.
Recovery for palbociclib is greater than 91.17%, while for fulvestrant it is greater than 77.52%.
Matrix effect for PAL is 10.25% and 6.92%, at the lower and higher measured concentration, and
for FUL it is -11.99% and -9.23%. Finally, the concentrations of palbociclib and fulvestrant in
plasma samples of real patients were determined, which demonstrated the applicability of the
method in therapeutic drug monitoring
Effect of iron nanoparticles functionalization on Er(III) ion sorption from aqueous solutions
No full textErbijevi spojevi najviše se koriste u izradi optičkih vodiča, lasera i u nuklearnim industrijama te stoga dospijevaju u okoliš. Zbog ograničenih resursa, učinkovito odvajanje erbija predmet je brojnih istraživanja. U ovom radu provedeni su u vodenom mediju eksperimenti sorpcije iona Er3+ pri različitim početnim koncentracijama na neutralnim nanočesticama željeza (nZVI) i nanočesticama željeza modificiranim s dipikolinskom kiselinom (nZVI/PDCA). Nefunkcionalizirane neutralne nanočestice željeza nZVI pokazale su iznimnu efikasnost sorpcije iona erbija (97-99 %) dok su modificirane čestice nZVI/PDCA pri istim dodanim koncentracijama iona erbija u vodenoj otopini za 16 % manje efikasne. Morfološke značajke nefunkcionaliziranih i modificiranih nanočestica prije i nakon sorpcije iona Er3+ dobivene metodom SEM ukazuju na sferične lančaste strukture nemodificiranih nanočestica te sitnije eliptične nakupine modificiranih nanočestica. Utvrđene razlike u morfologiji kod obje vrste čestica pridonose razumijevanju mogućih mehanizama sorpcije.Erbium compounds are mostly used in the production of optical guides, lasers and in the nuclear industry, and therefore end up in the environment. Due to limited resources, the efficient separation of erbium is the subject of numerous investigations. In this work, Er3+ ion sorption experiments in an aqueous medium at different initial concentrations on neutral iron nanoparticles (nZVI) and particles modified with dipicoline acid (nZVI/PDCA) were carried out. Non-functionalized nZVI nanoparticles showed exceptional erbium ion sorption efficiency (97-99 %), while modified nZVI/PDCA nanoparticles at the same added concentrations of erbium ions in water are 16% less efficient compared to non-functionalized nZVI particles. Morphological features of neutral iron nanoparticles and nanoparticles modified with dipicoline acid before and after Er3+ ion sorption obtained by the SEM method indicate spherical chain structures of bare particles and smaller elliptical clusters of modified particles. The determined differences in the morphology of both types of nanoparticles contribute to the understanding of possible sorption mechanisms
Review and analysis of stone processing production line
No full textKroz rad objašnjeni su osnovni teorijski pojmovi potrebni za razumijevanje napisanog, kao što su proizvodni i tehnološki proces, efektivnost, efikasnost, produktivnost te je dan uvid u kamen kao materijal. Opisano je poduzeće Gorica kamen d.o.o., djelatnost, proizvodni program, proizvod, tehnološki proces izrade, plan proizvodnje te elementi unutar iste (strojevi, alati i ostala oprema). Prikazani su podaci o izradi pojedinih proizvoda u nekoliko etapa. Sastavljen je dijagram toka od narudžbe kupca do montaže gotovog proizvoda. Objašnjena su vremena proizvodnje i gubici te su predložena moguća poboljšanja.Through the paper, the basic theoretical contepts necessery for understanding what is written are explained, such as the production and technological process, effectiveness, efficienci, productivity and the insight into the stone as material. The company Gorica kamen d.o.o., it's activity, production program, product, manufacturing process, prodaction plan and elements within it (machines, tools and othe equipment) are described. Data on the production of individual product in several stages are presented. A flow chart was drawn up from the customer's order to the assembly of the finished product. Production times are explained and possible improvements are suggested
Optimisation of tram driver's cabin steel structure considering fabrication technological aspects and crashworthiness
No full textTema ovog diplomskog rada je konstruirati i optimizirati čeličnu konstrukciju upravljačke kabine tramvaja, uzimajući u obzir tehnologičnost izrade te ponašanje prilikom sudara. Cilj konstrukcije upravljačke kabine tramvaja je osigurati sigurnost vozača. Konstrukcija mora biti konstruirana na način da odgovara obliku upravljačnice te s ciljem zadovoljavanja propisanih normi za sudare tračničkih vozila. U početku rada definirani su slučajevi prema kojima treba ispitati ponašanje konstrukcije prilikom sudara i napravljen je pregled literature u području lakih zavarenih konstrukcija. Sama konstrukcija je koncipirana i konstruirana te su izrađeni CAD model, proračunski model te je odrađena simulacija sudara.The theme of this master's thesis is to design and optimize the steel structure of a tram driver's cabin, taking into account manufacturability and behavior during collisions. The goal of the tram driver's cabin construction is to ensure the safety of the driver. The structure must be designed to fit the shape of the control cabin and to meet the prescribed norms for tram vehicle collisions. Initially, the thesis defines the cases according to which the behavior of the structure during collisions should be examined, and a literature review in the field of lightweight welded structures is conducted. The structure itself is then conceived and designed, the CAD model, computational models, and the collision simulation are carried out
Numerical analysis of the impact load on the side profile of the battery pack of electric vehicle
No full textElektrična vozila predstavljaju novi trend u automobilskoj industriji te sadrže brojne prednosti i nedostatke nad konvencionalnim vozilima. Glavni izazovi električnih vozila vezani su uz baterijski paket, odnosno njegovu sigurnost, masu i domet koje električno vozilo može ostvariti. Upravo zbog toga unutar ovog rada provedena je numerička simulacija udarnog opterećenja na bočni profil s ciljem smanjenja mase profila i povećanje volumena za baterijske ćelije uz zadržavanje mehaničkog integriteta, čime bi se osiguralo povećavanje gustoće energije baterijskog paketa i posljedično tome povećavanja dometa električnog vozila.
Unutar rada je provedeno istraživanje relevantnih normi te istraživanje i analiza trenutnih tržišnih rješenja s naprednom geometrijom bočnog profila koja namijenjena učinkovitoj apsorpciji energije bočnog udara. Na temelju toga modelirana i analizirana je inicijalna geometrija bočnog profila, a potom je geometrija iterirana s ciljem poboljšavanja apsorpcije energije udara i smanjenja pomaka bočnog profila prema unutrašnjosti baterijskog paketa. Za profil s najboljim svojstvima detaljno je prikazana analiza rezultata numeričke simulacije, a potom je i prikazan utjecaj smanjenja dimenzija bočnog profila na povećanje gustoće energije baterijskog paketa.Electric vehicles represent a new trend in the automotive industry, offering numerous advantages and disadvantages compared to conventional vehicles. The main challenges of electric vehicles are related to the battery pack, specifically its safety, weight, and the range the vehicle can achieve. For this reason, this study includes a numerical simulation of impact load on the side profile with the aim of reducing weight and volume while maintaining mechanical integrity, thereby increasing the energy density of the battery pack and, consequently, the range of the electric vehicle.
The study also involved researching relevant standards and analyzing current market solutions with advanced side profile geometries designed for effective energy absorption during side impacts. Based on this, the initial geometry of the side profile was modeled and analyzed, followed by iterative geometry modifications aimed at improving energy absorption and reducing the inward displacement of the side profile toward the battery pack. For the profile with the best properties, a detailed analysis of the numerical simulation results is presented, as well as the impact of reducing the side profile dimensions on increasing the energy density of the battery pack
Review and application of the method for life cycle assessment of the cogeneration process
No full textProcjena životnog ciklusa (eng. Life-Cycle Assessment – LCA) je metoda evaluacije učinaka koje proizvod, proces ili usluga ima na okoliš tijekom svog životnog vijeka, a koristi se kao alat za donošenje informiranih odluka u kontekstu održivog razvoja i okolišne odgovornosti. Rad pruža teorijski prikaz LCA analize koji uključuje pregled njene povijesti i razvoja kroz međunarodno prihvaćene standarde, kao što su ISO 14040 i ISO 14044 te metodološke smjernice i načela njenog provođenja. Uz usporedbu njihove dostupnosti te funkcionalnih i korisničkih aspekata, dan je osvrt na programske alate za provođenje LCA analize. Nadalje, razmotrena je uloga LCA principa u oblikovanju politika Europske unije i Hrvatske usmjerenih ka održivom razvoju. Na kraju, provedena je studija slučaja koja uključuje LCA analizu odabranog i prikazanog kogeneracijskog postrojenja. Cilj analize je identificirati, kvantificirati i procijeniti okolišne utjecaje povezane s proizvodnjom električne i toplinske energije iz drvne biomase.Life-Cycle Assessment (LCA) is a method of evaluating the environmental impact of a product, process or service throughout its life cycle. It is used as a tool to make informed decisions in the context of sustainable development and environmental responsibility. The paper provides a theoretical overview of LCA, including a review of its history and development through internationally accepted standards, such as ISO 14040 and ISO 14044, as well as the methodological guidelines and principles of its implementation. Along with a comparison of their availability and functional and user-oriented aspects, a overview of software tools for conducting LCA is given. Furthermore, the role of the LCA principles in shaping the policies of the European Union and Croatia aimed at sustainable development was discussed. Finally, a case study including LCA of the selected and presented cogeneration plant was carried out. The aim of the assessment is to identify, quantify and assess the environmental impacts associated with the production of electricity and heat from wood biomass
Seismogeological interpretation of a basinal succession of a prograding delta (Pannonian, eastern part of the Drava depression)
No full textU ovom radu su analizirani i interpretirani seizmogeološki podatci iz pet bušotina sa područja istočne Hrvatske, radi boljeg razumijevanja geološke prošlosti i prepoznavanja geoloških resursa. Pri tome je korišten 3D seizmički volumen popraćen geofizičkim podatcima mjerenja u pet bušotina kao i geološki podatci prikupljeni istražnim radovima u bušotini. Od geofizičkih podataka u bušotinama za korelaciju istraživanih naslaga korištene su karotažne krivulje spontanog potencijala, RT otpora i prirodne gama radioaktivnosti. Interpretirano je devet horizonata od kojih je izdvojeno četiri kao relevantnih za istraživanje. Za četiri izdvojena horizonta napravljene su strukturne vremenske karte i karte Root mean square atributa i atributa koherencije. Napravljene karte pokazuju prisutnost kanala i taložnih formi okarakteriziranih kao sediment waves (pješčani valovi). Analizom podataka bušotinskih jezgri i krivulja spontanog potencijala dokazana je prisutnost pretežito lapora i turbidita na području istraživanja. Svi rezultati upućuju na postojanje rezervoarskih stijena koje bi mogle imati dobro zatvaranje.This work focuses on the analysis of seismo-geological data from five wells drilled in eastern Croatia, with the goal of better understanding the geological history and identifying geological resources in the area. The work presented in this thesis integrates 3D seismic data, well data and geological data from well cores. Well data used in the work are wellbore logs of spontaneous potential (SP), resistivity, and gamma ray. From nine horizons interpreted in this work, four were selected as important for the research. Structural time maps, Root Mean Square (RMS) maps, and coherence maps were made for each of the selected horizons. The maps show the existence of channels and sedimentary forms characterized as sediment waves. Core data and SP logs have proven the existence of mostly marls and turbidites in the research area. The results suggest the existence of reservoir rocks that could have a good seal in regard of potential hydrocarbon research