Razvoj senzorskih receptorjev za optično zaznavanje raztopljenega amonijaka (NH3) in fosfatnih ionov (PO43-)

magistrsko delo

Ines Kavgić (Author), Aleksandra Lobnik (Mentor), Matejka Turel (Co-mentor)

Abstract

Pri spremljanju kvalitete vode moramo upoštevati mnogo različnih kemijsko-fizikalnih parametrov. V tem magistrskem delu se podrobneje dotaknemo vsebnosti dveh nutrientov; dušika in fosforja (oziroma amonijaka in fosfatnih ionov), kot predstavnikov anorganskih parametrov vode. Pri obeh analitih (amonijak - NH3 in fosfatni ion - PO43-) se soočamo tudi s problematiko njunega zaznavanja v vodnih medijih. V primeru NH3 trenutne razpoložljive metode ne omogočajo določevanja neioniziranega amonijaka (NH3), ločeno od amonijevega iona (NH4+), ki je znatno manj toksičen. V primeru PO43-, ki je znan povzročitelj evrofikacije, se poslužujemo spektrometrijske metode z amonijevim molibdatom, ki pa prav tako ne omogoča neposrednega in kontinuiranega zaznavanja analita v vodi. V predloženem magistrskem delu smo predstavili razvoj novih senzorskih receptorjev za optično zaznavanje in določevanje koncentracije neioniziranega amonijaka (NH3) in fosfatnih ionov (PO43-) v vodi. Uporabljeni indikatorji, ki so občutljivi na amonijak in fosfate, so kolorimetrični indikatorji (bromofenol modro – BPB, bromokrezol zeleno – BCG) oziroma lantanidni kompleksi (evropijev-tetraciklinski kompleks in terbijev kompleks), ki smo jih preko sol-gel postopka imobilizirali v polimerno osnovo ter nanesli na stekleni nosilec. Optični analizni metodi, ki smo ju uporabljali za zaznavanje analitov pa sta absorpcija in fluorescenca (oziroma fosforescenca). Razviti senzorski receptorji za zaznavanje NH3 omogočajo določevanje koncentracij analita v območju med 0,1 in 67,7 mg/L NH3 in v pH območju relevantnem po slovenski zakonodaji (pH 6,5-9). Pri razvoju senzorskih receptorjev za zaznavanje PO43- pa smo naleteli na nekaj težav, zato poleg rezultatov podajamo tudi možnosti in usmeritve za nadaljnje izboljšave.

Keywords

amonijak;fosfatni ion;optični kemijski senzor;sol-gel;absorpcija;fluorescenca;magistrske naloge;

Data

Language:	Slovenian
Year of publishing:	2016
Typology:	2.09 - Master's Thesis
Organization:	UM FS - Faculty of Mechanical Engineering
Publisher:	[I. Kavgić]
UDC:	544.72:543.426/.427(043.2)
COBISS:	19525142
Views:	2273
Downloads:	134
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Development of sensor receptors for optical detection of dissolved ammonia (NH3) and phosphate ions (PO43-)
Secondary abstract:	When monitoring the quality of water, many different chemical and physical parameters must be taken into consideration. In this thesis, two nutrients: nitrogen and phosphorus (ammonia and phosphate ions, respectively), as representatives of inorganic water quality parameters, are discussed. With both analytes (NH3 and PO43-), we are confronted with the problem of their detection in aqueous media. In the case of ammonia (NH3), the available methods do not enable the determination of non-ionized ammonia (NH3), separately from the ammonium ion (NH4+), which is significantly less toxic than its gaseous form. In the case of PO43-, which is one of the eutrophication agents, the spectrometric method with ammonium molybdate is usually applied, but this also does not allow a direct and continuous detection of this analyte in water. In the proposed thesis, we present the development of new sensor receptors for optical detection and determination of the concentration of non-ionized ammonia (NH3) and phosphate ions (PO43-) in water. The indicators used are sensitive to ammonia and phosphates, and are colorimetric indicators (bromophenol blue – BPB, bromocresol green – BCG) or lanthanide complexes (europium-tetracycline complex and terbium complex), respectively. Both have been immobilized into a polymer support via the sol-gel process and applied to a glass carrier. Absorption and fluorescence (i.e. phosphorescence) are the optical methods, which were used for the determination of the mentioned analytes. The developed sensor receptors allow the determination of NH3 in the concentration range between 0,1 and 67,7 mg/L, and at a pH range defined under Slovenian legislation (pH 6,5-9). In the case of PO43- sensor receptors, we encountered some problems in sensing, therefore, apart from results, we present options and suggestions for further improvements in developing PO43- sensitive layers.
Secondary keywords:	ammonia;phosphate ion;optical chemical sensors;sol-gel;absorption;fluorescence;
URN:	URN:SI:UM:
Type (COBISS):	Master's thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za strojništvo, Proizvodne tehnologije in sistemi
Pages:	XI, 76 str., [1] f. pril.
ID:	9120410