Development of a series of modified acridinium esters for use in clinical diagnostics

Acridinium esters (AE) have been traditionally used as chemiluminescent reporter molecules in clinical diagnostic assays due to their high quantum yields and detection limits in the attomole range. The aim was to produce a family of novel acridinium esters with modified chemiluminescent properties for use in clinical diagnostics. The hypothesis was that, by changing the substituents on the acridinium ring and the phenoxy ring of the acridinium ester molecule, a series of compounds with distinct chemiluminescent characteristics could be generated which would support dual analyte measurement. Two series of compounds were synthesized based on the addition of two methoxy (electron donating) or two bromo (electron withdrawing) groups to the 2 and 7 positions of the acridinium ring. Additionally, the effect of adding methyl or methoxy groups to the 2- and 6-positions of the phenoxy ring of the acridinium ester molecule was compared to the unsubstituted state. Five distinct acridinium esters were synthesized and their excitation and emission spectra determined. Two of the compounds were linked to a DNA oligonucleotide and incorporated into a Hybridisation Protection Assay (HPA), a direct and highly specific nucleic acid assay. The performance of these chemiluminescent labelled probes within the HPA (kinetics of light output and the rate of hydrolysis) was characterised. Major findings included a shift in the fluorometric spectra resulting from the substitution on the acridinium ring, resulting in the peak emission wavelengths of Nmethylacridone, 2,7-dibromo-10-methyl-9-acridone and 2,7-dimethoxy-10-methyl-9- acridone being observed at 430, 440 and 480 nm, respectively. Furthermore, the optimal pH for discrimination between hybridised and unhybridised probes for the dimethoxysubstituted acridinium ester 34cx was between 9.2 and 9.6 whilst the pH optimum of the routinely used unsubstituted compound 15 ranged from 7.5 to 8.5. Theoretically, the differential properties of dimethoxy-substituted AE DNA probes, the shift in emission wavelength and hydrolysis pH, may form the basis for a novel dual analyte HPA format to be developed

Investigation of archived accurate mass data in mass spectrometry.

"This thesis presents an investigation of mass measurement accuracy in mass spectrometry using archived accurate mass measurement data obtained on different types of mass spectrometry instruments. A magnetic sector was used as the "gold standard" analyzer and other data obtained on electrospray ionization fitted with Orbitrap and a MALDI time-of-flight instrument. More than 4500 accurate masses were obtained from the EPSRC National Mass Spectrometry Service Centre at Swansea University using the above instrument types. Different ionization methods are available; each has its own characteristics. In this study the ionization techniques used are chemical ionization (Cl), electron ionization (El), electrospray ionization (ESI), fast-atom bombardment (FAB) and matrix-assisted laser desorption/ionization (MALDI). These mass analyzers have different attributes, including the mass range, resolution and mass accuracy. Mass measurement accuracies (MMAs) are reported for a number of preferred techniques. Statistical calculations were made using various software pack-ages such as SPSS, AccMass (house software), Origin, Easyfit and Excel add-ins. The data contains view outliers which can significantly affect the accuracy and precision of the data as well as affecting the underlying statistical distribution predicted.

5-Bromo-1-(4-bromophenyl)isatin

In the title compound [systematic name: 5-bromo-1-(4-bromo­phen­yl)-2,3-di­hydro-1H-indole-2,3-dione], C14H7Br2NO2, all of the atoms except the C—H groups in the bromo­benzene ring lie on a (010) crystallographic mirror plane, with the benzene ring completed by reflection. The dihedral angle between the ring systems is constrained to be 90° by symmetry. In the crystal, mol­ecules are linked by weak C—H...Br inter­actions in the [001] direction and paired very weak C—H...O inter­actions to the same acceptor in the [100] direction, generating (010) sheets. Possible extremely weak π–π stacking occurs between the layers

Crystal structure of 2-((3-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-pyrazol-4-yl)methylene)-1H-indene-1,3(2H)-dione, C28H19N5O2

Abstract C28H19N5O2, monoclinic, Cc (no. 9), a = 13.9896(9) Å, b = 21.9561(14) Å, c = 7.1643(5) Å, β = 91.782(6)°, V = 2199.5(3) Å3, Z = 4, R gt(F) = 0.0632, wR ref(F 2) = 0.1727, T = 150(2) K.</jats:p

Impact of Moringa oleifera Leaf and Flaxseed on Lipid Oxidation and Microbiological Characteristics of Chicken Burger During Cold Storage

Background: Practice of making burgers out of chicken instead of red meat is gaining popularity. because of their high fat substance and on account of no social or strict limitations to the utilization of poultry. The present study aimed to assess effect of adding Moringa oleifera leaf and flaxseed combinations on lipid oxidation and microbiological traits of chicken burger during cold storage.Methods: In this study the pH, peroxide value, thiobarbituric acid (TBA) as well as microbiological characteristics of chicken burger formulated by various levels of Moringa oleifera leaf and flaxseed powder were evaluated. Samples were as follows: control=0%FS+0%MLP; T1=20%FS+0%MLP; T2=15%FS+5%MLP; T3=10%FS+10%MLP; T4=5%FS+15%MLP; andT5=0%FS+20%MLP.Results: The results showed that the pH value of burger samples supplemented with Moringa oleifera and flaxseed was decreased (P≤0.05) with an increasing period of storage and ranged between 3.5–5.1 and 3.3-4.9 when stored for 15 and 30 days, respectively.Conclusion: Peroxide values of T2, T3, T4 and T5 as well as the value of TBA within the MLP-treated and FS-treated samples (P 0.05) decreased with the progression of the storage period. Microbiological characteristics (P 0.05) were affected by the incorporation of MLP and FS in chicken burger treatments.Keywords: Burger; T.B.A.; Peroxide value; Contamination; Coliform bacteria;  E.coli; Moringa oleifera; Flaxseed   

Crystal structure of 2-(bis(4-methoxyphenyl)amino)-2-oxoacetic acid, C16H15NO5

Abstract C16H15NO5, monoclinic, P21/n (no. 14), a = 6.7689(5) Å, b = 45.219(3) Å, c = 10.1102(6) Å, β = 101.360(7)°, V = 3033.9(4) Å3, T = 298(2) K.</jats:p

Crystal structure of 2-(5-(4-fluorophenyl)-3-p-tolyl-4,5-dihydro-1H-pyrazol-1-yl)-4-(5-methyl-1-p-tolyl-1H-1,2,3-triazol-4-yl)thiazole, C29H25FN6S

Abstract C29H25FN6S, triclinic, P1̅, a = 7.5726(8) Å, b = 11.1428(13) Å, c = 16.412(2) Å, α = 91.823(5)°, β = 102.277(5)°, γ = 106.692(4)°, V = 1289.8(3) Å3, Z = 2, Rgt(F) = 0.079, wRref(F2) = 0.205, T = 296 K.</jats:p