Gelatin and Collagen from Sheepskin.

Abattoirs dispose of sheepskins as solid waste due to low price and poor demand for sheepskin leather. In principle, as an alternative to being disposed of in landfill, sheepskins can serve as a source of the protein collagen or the hydrolysis product, gelatin. In this research, sheepskins collected from abattoirs were used as a source of collagen.

Infrared Spectroscopy of Synovial Fluid Shows Accuracy as an Early Biomarker in an Equine Model of Traumatic Osteoarthritis.

Osteoarthritis is a leading cause of lameness and joint disease in horses. A simple, economical, and accurate diagnostic test is required for routine screening for OA. This study aimed to evaluate infrared (IR)-based synovial fluid biomarker profiling to detect early changes associated with a traumatically induced model of equine carpal osteoarthritis (OA).

Plasma and Synovial Fluid Cell-Free DNA Concentrations Following Induction of Osteoarthritis in Horses.

Biomarkers for osteoarthritis (OA) in horses have been extensively investigated, but translation into clinical use has been limited due to cost, limited sensitivity, and practicality. Identifying novel biomarkers that overcome these limitations could facilitate early diagnosis and therapy. This study aimed to compare the concentrations of synovial fluid (SF) and plasma cell-free DNA (cfDNA) over time in control horses with those with induced carpal OA.

Bone quality changes as measured by Raman and FTIR spectroscopy in primiparous cows with humeral fracture from New Zealand.

The occurrence of spontaneous humeral fractures in primiparous dairy cows from New Zealand prompted the study of bone material from affected cows to further characterize this condition and to outline a likely pathogenesis. Previous studies indicate that these cows developed osteoporosis due to periods of suboptimal bone formation followed by increased bone resorption during the period of lactation complicated by copper deficiency. We hypothesized that there are significant differences in the chemical composition/bone quality in bones from cows with spontaneous humeral fracture compared to cows without humeral fractures.

Complexation of Anthocyanin-Bound Blackcurrant Pectin and Whey Protein: Effect of pH and Heat Treatment.

A complexation study between blackcurrant pectin (BCP) and whey protein (WP) was carried out to investigate the impact of bound anthocyanins on pectin−protein interactions. The effects of pH (3.5 and 4.

Optical Detection of CoV-SARS-2 Viral Proteins to Sub-Picomolar Concentrations.

The emergence of a new strain of coronavirus in late 2019, SARS-CoV-2, led to a global pandemic in 2020. This may have been preventable if large scale, rapid diagnosis of active cases had been possible, and this has highlighted the need for more effective and efficient ways of detecting and managing viral infections. In this work, we investigate three different optical techniques for quantifying the binding of recombinant SARS-CoV-2 spike protein to surface-immobilized oligonucleotide aptamers.

The Binary Iodine-Chlorine Octahalide Series [I Cl ] (n=3, 3.6, 4).

The octanuclear iodine-chlorine interhalides [I Cl ] and [I Cl ] were prepared in two steps. Firstly, addition of ICl to the triaminocyclopropenium chloride salt [C (NEt ) ]Cl forms the trihalide ICl salt, secondly, addition of half an equivalent of I or ICl, respectively, gave the desired products upon crystallization at low temperature. The non-stoichiometric octahalide [I Cl ] was obtained after heating a CH Cl solution of the ICl salt to reflux for 2 hours followed crystallization.

Rational Synthesis, Structures and Properties of the Ionic Liquid Binary Iodine-Bromine Octahalide Series [I Br ] (n=0, 2, 3, 4).

A series of octanuclear iodine-bromine interhalides [I Br ] (n=0, 2, 3, 4) were prepared systematically in two steps. Firstly, addition of a dihalogen (Br or IBr) to the triaminocyclopropenium bromide salt [C (NEt ) ]Br forms the corresponding trihalide salt with Br or IBr anions, respectively. Secondly, addition to Br of half an equivalent of Br gives the octabromine polyhalide [Br ] , whereas addition to IBr of half an equivalent of Br , IBr or I gives the corresponding interhalides: [I Br ] , [I Br ] , and [I Br ] , respectively.

Diels-Alder Reaction of Anthranilic Acids: A Versatile Route to Dense Monolayers on Flat Edge and Basal Plane Graphitic Carbon Substrates.

Methods that reliably yield monolayers of covalently anchored modifiers on graphene and other planar graphitic materials are in demand. Covalently bonded groups can add functionality to graphitic carbon for applications ranging from sensing to supercapacitors and can tune the electronic and optical properties of graphene. Limiting modification to a monolayer gives a layer with well-defined concentration and thickness providing a minimum barrier to charge transfer.

Toward an iron(II) spin-crossover grafted phosphazene polymer.

Two new cyclotriphosphazene ligands with pendant 2,2':6',2″-terpyridine (Terpy) moieties, namely, (pentaphenoxy){4-[2,6-bis(2-pyridyl)]pyridoxy}cyclotriphosphazene (L(1)), (pentaphenoxy){4-[2,6-terpyridin-4-yl]phenoxy}cyclotriphosphazene (L(2)), and their respective polymeric analogues, L(1P) and L(2P), were synthesized. These ligands were used to form iron(II) complexes with an Fe(II)Terpy(2) core. Variable-temperature resonance Raman, UV-visible, and Mössbauer spectroscopies with magnetic measurements aided by density functional theory calculations were used to understand the physical characteristics of the complexes.

Innovative approach to investigating the microstructure of calcified tissues using specular reflectance Fourier transform-infrared microspectroscopy and discriminant analysis.

Although bone fracture has become a serious global health issue, current clinical assessments of fracture risk based on bone mineral density are unable to accurately predict whether an individual is likely to suffer a fracture. There is increasing recognition that the chemical structure and composition, or microstructure, of mineralized tissues has an important role to play in determining the fracture resistance of bone. The objective of this preliminary study was to evaluate the use of specular reflectance Fourier transform infrared (SR FT-IR) microspectroscopy in conjunction with discriminant analysis as an innovative technique for providing future insights into the origins of orthopedic abnormalities.

Luminescent rhenium(I)-dipyrrinato complexes.

The first Re(I)-dipyrrinato complexes are reported. Complexes with the general formulas fac-[ReL(CO)(3)Cl](-), fac-[ReL(CO)(3)PR(3)], and [ReL(CO)(2)(PR(3))(PR'(3))] have been prepared, where L is one of a series of meso-aryl dipyrrinato ligands. Access to these complexes proceeds via the reaction of [Re(CO)(5)Cl] with the dipyrrin (LH) to produce fac-[ReL(CO)(3)Cl](-).

Mechanically interlocked gold and silver nanoparticles using metallosupramolecular catenane chemistry.

We have employed the toolbox of metallosupramolecular chemistry to mechanically interlock gold and silver nanoparticles. A specifically designed PEGthiol-functionalized bis(phenanthroline)copper(I) complex acts to 'catenate' the nanoparticles. The interlocked assemblies were characterised by three complementary techniques: DLS, SERS and TEM.

Exciton coupling in coordination compounds.

This Perspective reviews the impact of exciton coupling on the spectroscopic properties of coordination compounds. Exciton coupling features arise in electronic absorption and circular dichroism spectra when chromophores are brought into close spatial proximity, for example by coordination to a metal centre. The analysis of these features can reveal much information such as the geometry of a complex and its absolute configuration.

Strongly absorbing pi-pi* states in heteroleptic dipyrrin/2,2'-bipyridine ruthenium complexes: excited-state dynamics from resonance raman spectroscopy.

A recently reported new class of ruthenium complexes containing 2,2'-bipyridine and a dipyrrin ligand in the coordination sphere exhibit both strong metal-to-ligand charge-transfer (MLCT) and pi-pi* transitions. Quantitative analysis of the resonance Raman scattering intensities and absorption spectra reveals only weak electronic interactions between these states despite direct coordination of the bipyridyl and dipyrrin ligands to the central ruthenium atom. On the basis of DFT calculations and time-dependent DFT (TD-DFT), we propose that the electronic excited states closely resemble "pure" MLCT and pi-pi* states.

Chromophoric dipyrrin complexes capable of binding to TiO2: synthesis, structure and spectroscopy.

The synthesis, characterisation, and TiO2 binding studies of a series of chromophoric complexes of 5-(4-carboxyphenyl)-4,6-dipyrrin (L(b)) are presented. The synthesis of [Ru(bipy)(L(b))2] (bipy = 2,2-bipyridine), [Rh(L(b))3], and [Pd(L(b))2] was achieved by initial coordination of 5-(4-methoxycarbonylphenyl)-4,6-dipyrrin (L(a)) followed by hydrolysis of the ester group. The carboxyl groups that are located on the peripheries of these complexes are able to engage in intermolecular hydrogen bonding interactions in the solid state, as revealed by X-ray crystallography.

Heteroleptic dipyrrin/bipyridine complexes of ruthenium(II).

The synthesis and characterization of a series of heteroleptic dipyrrinato/2,2'-bipyridine complexes of ruthenium(II) are reported. Spectroscopic analysis, including resonance Raman, indicates that the complexes are only weakly emissive and that the dipyrrin and Ru --> bipyridine (metal-to-ligand charge transfer) chromophores are uncoupled.

Metal-metal communication in copper(II) complexes of cyclotetraphosphazene ligands.

Copper(II) chloride and bromide react with the pyridyloxy-substituted cyclotetraphosphazene ligands, octakis(2-pyridyloxy)cyclotetraphosphazene (L(1)), and octakis(4-methyl-2-pyridyloxy)cyclotetraphosphazene (L(2)), to form the dimetallic complexes, [L(CuX2)2] (L = L(1), X = Br; L = L(2), X = Cl or Br), and [{L(1)(CuCl2)2}n]. Single crystal X-ray crystallography shows the complex [{L(1)(CuCl2)2}n] to be a coordination polymer propagated by interligand "Cu(mu-Cl)2Cu" bridges whereas [L(2)(CuCl2)2] forms discrete dimetallic cyclotetraphosphazene-based moieties. The variable temperature magnetic susceptibility data for [{L(1)(CuCl2)2}n] are consistent with a weak antiferromagnetic exchange interaction between the copper(II) centers occurring via the bridging chloride ions.

Using internal coordinates to describe photoinduced geometry changes in MLCT excited states.

A resonance Raman intensity analysis of the metal-to-ligand charge-transfer (MLCT) transition for the rhenium compound Re(2-(2'-pyridyl)quinoxaline)(CO)(3)Cl (RePQX) is presented. Photoinduced geometry changes are calculated, and the results are presented using the vibrational normal modes and the redundant internal coordinates. A density functional theory calculation is used to determine the ground-state nonresonant Raman spectrum and a transformation matrix that transforms the redundant internal coordinates into the normal modes.

Resonance raman excitation profile of a ruthenium(II) complex of dipyrido[2,3-a:3',2'-c]phenazine.

The lowest energy transition of [Ru(CN)(4)(ppb)](2-) (ppb = dipyrido[2,3-a:3',2'-c]phenazine), a metal-to-ligand charge transfer, has been probed using resonance Raman spectroscopy with excitation wavelengths (488, 514, 530, and 568 nm) spanning the lowest energy absorption band centered at 522 nm. Wave packet modeling was used to simultaneously model this lowest energy absorption band and the cross sections of the resonance Raman bands at the series of excitation wavelengths across this absorption band. A fit to within +/-20% was obtained for the Raman cross sections, close to the experimental uncertainty which is typically 10-20%.

Structural changes upon photoexcitation into the metal-to-ligand charge-transfer state of [Cu(pqx)(PPh3)2]+ probed by resonance Raman spectroscopy and density functional theory.

The structural changes that occur when [Cu(pqx)(PPh(3))(2)](+) (pqx is 2-(2'-pyridyl)quinoxaline) undergoes excitation through a metal-to-ligand charge-transfer (MLCT) transition are investigated using resonance Raman excitation profiles coupled with density functional theory (DFT). The DFT calculations predict bond lengths to within 3 pm and absolute deviations of 7 cm(-1) for the vibrational frequencies of [Cu(pqx)(PPh(3))(2)](+). TD-DFT calculations of oscillator strengths (f = 0.