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Characterisation of the water treatment sludge (WTS) generated in drinking water treatment plants (DWTPs) is crucial to define alternatives for its adequate management, including potential reuse options. To define these alternatives, it is necessary to evaluate rainfall seasonality effect on WTS production and its physical and chemical characteristics. This study assessed the production and characterisation of four types of alum-based WTS. The WTS was generated in a pilot-scale system from different raw water turbidities (i.e., low: <5 NTU, medium: 5-10 NTU, high: ≥10 NTU, and very high turbidity: ∼300 NTU) and coagulant doses. To estimate WTS production, mathematical models based on variables such as raw water turbidity, coagulant dosage, and organic matter removed were used. The WTS characterisations included physical (solids and particle size distribution), chemical (metallic oxides, pH, mineral phases), and surface properties (functional groups and zero-charge point pH). The modified Kawamura model presented the best fit (R2 = 1.0, RMSE = 0.1062 and the lower Akaike Information Criterion) for the estimation of WTS production, indicating that at the DWTPs, it is possible to make sludge production projections using only two simple variables: coagulant dose and the raw water turbidity. The four types of WTS consist mainly of amorphous materials (45-65 %), featuring some mineral phases and exhibiting high contents of Al (Al2O3: 30-34 %), Si (SiO2: 21-26 %) and Fe (Fe2O3: 11-13 %). Nevertheless, very high turbidity WTS shows variations in its characteristics, notably a heightened content of clays. As a result of the high concentrations of Al and Fe, the WTS has the potential to be used as coagulants or for the recovery of coagulants, especially low turbidity WTS, which is produced from water with low turbidity and organic matter. The presence of aluminium-silicate clays and the surface functional groups of the silica network suggest that WTS, particularly very high turbidity WTS, also has the potential to be raw materials for generating adsorbents. The potential applications of WTS in coagulation and adsorption can be leveraged in wastewater treatment, promoting the circular economy in the water sector.

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Exopolysaccharide (EPS) producing Lactic Acid Bacteria (LAB) species can be presented in distinct environments. In this study, Turkish fermented sausage (sucuk) was tested for the presence of EPS producer LAB strains and slimy-mucoid colonies were selected for further tests. Among the isolates, Weissella confusa strain S6 was identified and tested for the physicochemical characterisation of its EPS. This strain was found to produce 0.74 g L-1 of EPS in modified BHI medium conditions. Structural characterisation of EPS S6 by 1H and 13C NMR demonstrated that EPS S6 was a highly branched dextran type glucan formed by mainly (1 â†’ 2)-linked α-d-glucose units together with low levels of (1 â†’ 3)-linked α-d-glucose units as branching points. This structure was further confirmed by methylation analysis detected by GC-MS. An average molecular weight of 8 × 106 Da was detected for dextran S6. The FTIR analysis supported the dextran structure and revealed the presence of distinct functional groups within dextran S6 structure. A strong thermal profile was observed for dextran S6 detected by DSC and TGA analysis and dextran S6 revealed a degradation temperature of 289 °C. In terms of physical status, dextran S6 showed amorphous nature detected by XRD analysis. SEM analysis of dextran S6 demonstrated its rough, compact and porous morphology whereas AFM analysis of dextran S6 detected in its water solution showed the irregularity with no clear cross-link within the dextran chains. These technological features of dextran S6 suggests its potential to be used for in situ or ex situ application during meat fermentations.

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This study details the formation and characterisation of a novel nicotinamide adenine dinucleotide (NAD+)-associated polymeric nanoparticle system. The development of a polyelectrolyte complex (PEC) composed of two natural polyelectrolytes, hyaluronic acid and poly(L-lysine), and an evaluation of its suitability for NAD+ ocular delivery, primarily based on its physicochemical properties and in vitro release profile under physiological ocular flow rates, were of key focus. Following optimisation of formulation method conditions such as complexation pH, mode of addition, and charge ratio, the PEC was successfully formulated under mild formulation conditions via polyelectrolyte complexation. With a size of 235.1 ± 19.0 nm, a PDI value of 0.214 ± 0.140, and a zeta potential value of - 38.0 ± 1.1 mV, the chosen PEC, loaded with 430 µg of NAD+ per mg of PEC, exhibited non-Fickian, sustained release at physiological flowrates of 10.9 ± 0.2 mg of NAD+ over 14 h. PECs containing up to 200 µM of NAD+ did not induce any significant cytotoxic effects on an immortalised human corneal epithelial cell line. Using fluorescent labeling, the NAD+-associated PECs demonstrated retention within the corneal epithelium layer of a porcine model up to 6 h post incubation under physiological conditions. A study of the physicochemical behaviour of the PECs, in terms of size, zeta potential and NAD+ complexation in response to environmental stimuli,highlighted the dynamic nature of the PEC matrix and its dependence on both pH and ionic condition. Considering the successful formation of reproducible NAD+-associated PECs with suitable characteristics for ocular drug delivery via an inexpensive formulation method, they provide a promising platform for NAD+ ocular delivery with a strong potential to improve ocular health.

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The present study is based on a multidisciplinary approach carried out for the first time on Anacyclus pyrethrum var. pyrethrum and Anacyclus pyrethrum var. depressus, two varieties from the endemic and endangered medicinal species listed in the IUCN red list, Anacyclus pyrethrum (L.) Link. Therefore, morphological, phytochemical, and genetic characterisations were carried out in the present work. Morphological characterisation was established based on 23 qualitative and quantitative characters describing the vegetative and floral parts. The phytochemical compounds were determined by UHPLC. Genetic characterisation of extracted DNA was subjected to PCR using two sets of universal primers, rbcL a-f/rbcL a-R and rpocL1-2/rpocL1-4, followed by sequencing analysis using the Sanger method. The results revealed a significant difference between the two varieties studied. Furthermore, phytochemical analysis of the studied extracts revealed a quantitative and qualitative variation in the chemical profile, as well as the presence of interesting compounds, including new compounds that have never been reported in A. pyrethrum. The phylogenetic analysis of the DNA sequences indicated a similarity percentage of 91%. Based on the morphological characterisation and congruence with the phytochemical characterisation and molecular data, we can confirm that A. pyrethrum var. pyrethrum and A. pyrethrum var. depressus represent two different taxa.

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Biomass-derived products, such as lignin, are interesting resources for energetic purposes. Lignin is a natural polymer that, when added to the anode of an alkaline exchange membrane water electrolyser, enhances H2 production rates and efficiencies due to the substitution of the oxygen evolution reaction. Higher efficiencies are reported when different catalytic materials are employed for constructing the lignin anolyte, demonstrating that lower catalytic loadings for the anode improves the H2 production when compared to higher loadings. Furthermore, when a potential of -1.8 V is applied, higher gains are obtained than when -2.3 V is applied. An increase of 200% of H2 flow rates with respect to water electrolysis is reported when commercial lignin is used coupled with Pt-Ru at 0.09 mg cm-2 and E = -1.8 V is applied at the cathode. This article provides deep information about the oxidation process, as well as an optimisation of the method of the lignin electro-oxidation in a flow-reactor as a pre-step for an industrial implementation.

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To promote the application of almond expellers, sweet almond expeller globulin (amandin) was extracted for the preparation of bioactive peptides. After dual enzymatic hydrolysis, Sephadex G-15 gel isolation, reverse-phase high-performance liquid chromatography purification and ESI-MS/MS analysis, two novel peptides Val-Asp-Leu-Val-Ala-Glu-Val-Pro-Arg-Gly-Leu (1164.45 Da) and Leu-Asp-Arg-Leu-Glu (644.77 Da) were identified in sweet almond expeller amandin hydrolysates. Leu-Asp-Arg-Leu-Glu (LDRLE) of excellent zinc-chelating capacity (24.73 mg/g) was selected for preparation of peptide-zinc chelate. Structural analysis revealed that zinc ions were mainly bonded to amino group and carboxyl group of LDRLE. Potential toxicity and some physicochemical properties of LDRLE and Val-Asp-Leu-Val-Ala-Glu-Val-Pro-Arg-Gly-Leu (VDLVAEVPRGL) were predicted in silico. The results demonstrated that both LDRLE and VDLVAEVPRGL were not toxic. Additionally, zinc solubility of LDRLE-zinc chelate was much higher than that of zinc sulphate and zinc gluconate at pH 6.0−10.0 and against gastrointestinal digestion at 37 °C (p < 0.05). However, incubation at 100 °C for 20−60 min significantly reduced zinc-solubility of LDRLE-zinc chelate. Moreover, the chelate showed higher zinc transport ability in vitro than zinc sulphate and zinc gluconate (p < 0.05). Therefore, peptides isolated from sweet almond expeller amandin have potential applications as ingredient of zinc supplements.

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It is evident from the literature that research on the treatment of leachate generated from municipal solid waste (MSW) landfills has been a focus area of environmental management. However, the available information is discrete because most studies have reported only one or a couple of aspects of either closed or active MSW landfill leachate treatment. Hence, this investigation has focused on comprehensive attributes of both closed landfill leachate (CLL) and active landfill leachate (ALL), including generation, characterisation, and toxicity assessment to quantify and establish their pollution potential. The results indicated that CLL generation is higher (188.59 m3/d) than ALL (49.53 m3/d). The concentrations of principal physical, chemical, and biological constituents and concomitant leachate pollution index were higher in CLL (33.20) than in ALL (26.65). Furthermore, the germination indices of CLL (57.48) and ALL (79.14) and tail DNA damage of CLL (56.49%) and ALL (23.8%) ratified greater phytotoxicity and genotoxicity potential, respectively of CLL over ALL. The reasons for the variations in the generation, characteristics, and toxicity of CLL and ALL were discussed in detail. Evaluation of the commonly used landfill leachate treatment methods through the analytical hierarchy process confirmed that the activated sludge process and Fenton oxidation process are the most and least preferred treatment methods. The comprehensive investigation of CLL and ALL have established their pollution potential and the inevitable necessity for their treatment. The findings of this investigation will serve as a ready reference for researchers from academia and industry who work on the monitoring, treatment, and management of landfill leachate.

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Biochar is known to be a highly adsorptive material, especially when the biochar is altered by activation to further increase its sorption ability. Little information, however, is available on the potential reversibility of both ammonium (NH4+) and nitrate (NO3-) sorption on the inherent biochar pH. The objective of our study was to characterise biochars made using different pyrolysis conditions from five various plant materials and rubber tyre, and to use them to investigate the biochar properties responsible for NH4+ and NO3- adsorption and desorption. The rubber tyre, maize stover and sugarcane pith were the weakest adsorbing biochars (5.7-7.8 mg g-1) and best described by the Freundlich adsorption isotherm. The grape pip, grape skin and pine wood biochars had adsorption capacities in the range 8.3-9.4 mg NH4+ g-1 and best described by a linear adsorption isotherm at 100 mg L-1. The NH4+ adsorption results were associated with physisorption which implies that they can act as slow release NH4+ fertilisers if NH4+ is bioavailable. The six biochars had NO3- adsorption capacities in the range 15.2-15.9 mg g-1 and were well fitted to the linear adsorption isotherm at 100 mg L-1. All six biochars had a stronger NO3- removal affinity (82-89%) compared to NH4+ (33-39%). Adsorbed nitrate was not desorbable (0.01-0.23%) compared to adsorbed NH4+ which was 53-60% desorbable. The desorption result was possibly due to NO3- competing redox reactions or NO3- being too strongly adsorbed for extraction. Desorption of NH4+ was associated with biochar net negative pH values and volatilisation of ammonia.

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Understanding what maturity entails for bone, when it arrives, and its pre- and post-maturity traits and properties are very important for understanding its evolution and physiology. There is a clear but fine distinction between the chronological age of bone (the age of its donor) and the tissue age of the bone packets it comprises at the microscopic level. Whole bone fragility changes with age due to mass and architecture effects, but so do the properties of bone at the tissue level. Tissue age and tissue-level properties are therefore increasingly attracting a great deal of attention recently. The present study investigated compositional and material changes in the hydroxyapatite crystals, the collagenous phase, changes in bone matrix composition and its nanoindentation properties and their decline with chronological age in later life. The aim was to track the age threshold at which cortical bone arrives at maturity and what happens following that threshold. To do so FTIR, DSC/TGA, XRD, nanoindentation and microindentation were used to investigate rib cortical bone material across a cohort of 86 individuals from one ethnic group with age spanning between 17 and 82 years. Results of this cross-sectional study showed a clear increase in mineral content relative to the organic and water contents across all ages. Furthermore, an increase in crystal size and consequent decrease in strain (coherence length) was detected associated with secondary mineralisation and an increase in carbonate substitution. Overall, we observe a number of modifications which contribute to a typical functional behaviour of bone showing an increase in both indentation modulus and hardness until the age of about 35 after which both of these properties decline gradually and concomitantly to other physicochemical changes and seemingly until the end of one's life.

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Nanotechnology-based health products are providing innovative solutions in health technologies and the pharmaceutical field, responding to unmet clinical needs. However, suitable standardised methods need to be available for quality and safety assessments of these innovative products prior to their translation into the clinic and for monitoring their performance when manufacturing processes are changed. The question arises which technological solutions are currently available within the scientific community to support the requested characterisation of nanotechnology-based products, and which methodological developments should be prioritized to support product developers in their regulatory assessment. To this end, the work presented here explored the state-of-the-art methods to identify methodological gaps associated with the preclinical characterisation of nanotechnology-based medicinal products and medical devices. The regulatory information needs, as expressed by regulatory authorities, were extracted from the guidance documents released so far for nanotechnology-based health products and mapped against available methods, thus allowing an analysis of methodological gaps and needs. In the first step, only standardised methods were considered, leading to the identification of methodological needs in five areas of characterisation, including: (i) surface properties, (ii) drug loading and release, (iii) kinetic properties in complex biological media, (iv) ADME (absorption, distribution, metabolism and excretion) parameters and (v) interaction with blood and the immune system. In the second step, a detailed gap analysis included analytical approaches in earlier stages of development, and standardised test methods from outside of the nanotechnology field that could address the identified areas of gaps. Based on this analysis, three categories of methodological needs were identified, including (i) method optimisation/adaptation to nanotechnological platforms, (ii) method validation/standardisation and (iii) method development for those areas where no technological solutions currently exist. The results of the analysis presented in this work should raise awareness within the scientific community on existing and emerging methodological needs, setting priorities for the development and standardisation of relevant analytical and toxicological methods allowing the development of a robust testing strategy for nanotechnology-based health products.

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The lack of trypsin in the intestines may end up with malnutrition; thus, trypsin replacement therapy is required in such cases. The main objective of this study is to formulate and evaluate polymeric nanocapsule (PNC) systems able to deliver trypsin to the small intestines with the minimal release in the stomach with the maximum biological activity. Four nanocapsule formulations were prepared by double emulsion/evaporation method as w/o/w and s/o/w. Particle size, encapsulation efficiencies, drug release in simulated gastric fluids (SGF) and simulated intestinal fluids (SIF), morphology, the biological activity of encapsulated trypsin and shelf-life stability were investigated for all formulations. All formulations had a spherical shape with submicron size, and encapsulation efficiency more than 80%. The biological activity of encapsulated trypsin was significantly affected by the amount of trehalose and whether the formulations were prepared as s/o/w or w/o/w (P < 0.05). Most of the encapsulated protein was released sustainedly at the target site (SIF) over 24 h with minimum amount release in the gastric fluids. Also, more than 90% of physical integrity trypsin encapsulated in all formulations was retained after storage under chilled conditions for six months. However, the enzymatic assay results show that with low trehalose content, the biological activity was low, while increasing the trehalose amount increased the shelf stability to reach around 100% after six months of the study. The results obtained in this research work clearly indicated a promising potential of controlled release polymeric nanocapsules containing trypsin to target the small intestine and protect trypsin from the harsh condition facing the proteins during the process of preparation or the period of storage.

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Coal combustion product in the form of fly ash has been sieved and successfully utilised as a main substrate and a carrier of silicon and aluminium in a set of hydrothermal syntheses of zeolites. The final product was abundant in zeolite X phase (Faujasite framework). Raw fly ash as well as its derivatives, after being sieved (fractions: ≤ 63, 63-125, 125-180 and ≥ 180 µm), and the obtained zeolite materials were subjected to mineralogical characterisation using powder X-ray diffraction, energy-dispersive X-ray fluorescence, laser diffraction-based particle size analysis and scanning electron microscopy. The influence of fraction separation on the zeolitization process under hydrothermal synthesis was investigated. Analyses performed on the derived zeolite X samples revealed a meaningful impact of the given fly ash fraction on synthesis efficiency, chemistry, quality as well as physicochemical properties, while favouring a given morphological form of zeolite crystals. The obtained zeolites possess great potential for use in many areas of industry and environmental protection or engineering.

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Electrospraying or electrohydrodynamic atomisation, i.e. the formation of tiny droplets from a jet of conductive liquid under the influence of an electric field, has been gaining in popularity as a particle engineering technique in recent years. In addition to general benefits for particle engineering, e.g. the ability to generate nanometre sized particles with a very narrow size distribution, electrospraying also possesses a number of characteristics, like its applicability at ambient conditions, which could make it especially interesting for formulating therapeutic proteins. However, as fully aqueous solutions of proteins tend to have relatively high electrical conductivities and surface tensions, obtaining a stable Taylor cone-jet mode for these solutions is inherently challenging. This is why in the majority of studies reporting the successful electrospraying of proteins, either emulsions, aqueous suspensions or a mixture of water and one or more organic solvents were used instead of fully aqueous solutions. Therefore, an ab initio electrospraying formulation development study was conducted, using only fully aqueous feed solutions containing protein stabilising excipients commonly used in spray- and freeze-drying of therapeutic proteins. The study included bovine serum albumin (BSA) as a model protein and consisted out of two parts: (1) a one parameter at a time screening study, designed to improve the understanding of how various formulation components influence relevant physicochemical properties and the electrospraying process and (2) two subsequent mixture design of experiments (DoE) studies, designed to aid in the statistical description and prediction of the influence of different protein-excipient combinations on the electrospraying process. Additionally, the influence of physicochemical properties relevant to the electrospraying process, i.e. the volumetric mass density, electrical conductivity, kinematic viscosity and surface tension, was assessed for all feed solutions included in the study.

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Aim: Optimum conditions of umbu juice spray drying were selected using inlet air temperature (T), feed flow rate (F) and 10-DE maltodextrin concentration (CMD) as independent variables, and water activity, moisture content, hygroscopicity and phenolic compounds retention as responses.Methods: Powders water activity was determined with a water activity metre, moisture content and hygroscopicity gravimetrically, total phenolics spectrophotometrically, apparent and absolute density, porosity and solubility by standard methods, particle size by laser diffraction, and morphology by Scanning Electron Microscopy. Nectars sensory analysis was based on acceptance, purchase intention and multiple comparison preference tests. Powder stability was checked at 25 °C varying water activity and storage time in the ranges 0.1-0.3 and 30-90 days, respectively.Results: Powders prepared at T = 110 °C, F = 0.84 L/h, CMD=10% and T = 140 °C, F = 0.60 L/h, CMD=10% gave the best microparticles and sensory results. The former showed properties suitable for industrial production.Conclusion: These findings may promote umbu powder industrial exploitation.

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The present research work summarises the development of an in situ gelling ophthalmic nanoemulsion of brinzolamide providing sustained release and prolonged therapeutic effect for the treatment of glaucoma. Nanoemulsions were prepared using castor oil, polyoxyl 35 castor oil and polysorbate 80 and with gellan gum as the in situ gelling agent. Formulations were screened based on globule size, Zeta potential, in vitro drug release and stability towards phase separation and sol to gel conversion upon storage. Selected formulations exhibiting a low mean globule diameter (< 160 nm), narrow size distribution (polydispersity index < 0.3), quick in vitro gelling time (< 15 s) and stability for at least 6 months at 25 °C/40% RH and 40 °C/25% RH were evaluated for intraocular pressure (IOP)-lowering efficacy studies using glaucomatous rabbits. Tested nanoemulsion formulations were well tolerated and significantly decreased IOP relative to saline and placebo controls (p < 0.005). Furthermore, an appreciable increase in the area under change in IOP from baseline (ΔIOP) vs. time curve and a longer mean residence time (MRT) was also observed for the test formulations compared with commercially available suspension of brinzolamide (Azopt, Alcon Laboratories, USA). Thus, nanoemulsion formulations containing in situ gelling polymer may serve as improved drug delivery system providing superior therapeutic efficacy and better patient compliance for the treatment of glaucoma. . Graphical abstract.

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Aims@#This present study focused on purification of fungal β-mannanase produced by Aspergillus niger USM F4 and also physicochemical characterisation of the purified enzyme.@*Methodology and results@#The purified β-mannanase with a molecular mass of ~47.4 kDa was demonstrated on SDSPAGE gel. The enzyme signified a purification degree of 4-fold, with final specific activity of 196.42 U/mg. It reached an optimum catalytic activity at pH 4.0 and 60 °C. The thermal stability of the enzyme was up to 70 °C and maintained the 50% activity after 30 min at 80 °C. Meanwhile, the pH stability was in the range of pH 3.0-9.0 and a 30 min half-life at pH 10.0. All chemical substances manifested an inhibitory effect on purified β-mannanase, with SDS (28.16 ± 0.05% residual activity) as the strongest inhibitor, followed by cupric ion (Cu2+) (49.51 ± 0.09% residual activity). As a whole, the enzyme displayed a substrate specificity in the order of locust bean gum (LBG) > carboxymethylcellulose > soluble starch > xylan from oat spelt > α-cellulose. Its preference for LBG has generated the Km and Vmax values of 0.20 mg/mL and 9.82 U/mL, respectively.@*Conclusion, significance and impact of study@#The outcomes of our study offer potential for use at industrial scales, particularly in the oligosaccharides production that involve acid-related activity, wide-ranging temperature and pH stability.

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The aim of the present work is to develop nanoemulsions (NEs), nanosized emulsions, manufactured for improving the delivery of active pharmaceutical ingredients. In particular, nanoemulsions composed of Neem seed oil, contain rich bioactive components, and Tween 20 as nonionic surfactant were prepared. A mean droplet size ranging from 10 to 100 nm was obtained by modulating the oil/surfactant ratio. Physicochemical characterisation was carried out evaluating size, ζ-potential, microviscosity, polarity and turbidity of the external shell and morphology, along with stability in simulated cerebrospinal fluid (CSF), activity of Neem oil alone and in NEs, HEp-2 cell interaction and cytotoxicity studies. This study confirms the formation of NEs by Tween 20 and Neem oil at different weight ratios with small and homogenous dimensions. The antioxidant activity of Neem oil alone and in NEs was comparable, whereas its cytotoxicity was strongly reduced when loaded in NEs after interaction with HEp-2 cells.

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For the creation of scaffolds in tissue engineering applications, it is essential to control the physical morphology of fibres and to choose compositions which do not disturb normal physiological function. Collagen, the most abundant protein in the human body, is a well-established biopolymer used in electrospinning compositions. It shows high in-vivo stability and is able to maintain a high biomechanical strength over time. In this study, the effects of collagen type I in polylactic acid-drug electrospun scaffolds for tissue engineering applications are examined. The samples produced were subsequently characterised using a range of techniques. Scanning electron microscopy analysis shows that the fibre morphologies varied across PLA-drug and PLA-collagen-drug samples - the addition of collagen caused a decrease in average fibre diameter by nearly half, and produced nanofibres. Atomic force microscopy imaging revealed collagen-banding patterns which show the successful integration of collagen with PLA. Solid-state characterisation suggested a chemical interaction between PLA and drug compounds, irgasan and levofloxacin, and the collagen increased the amorphous regions within the samples. Surface energy analysis of drug powders showed a higher dispersive surface energy of levofloxacin compared with irgasan, and contact angle goniometry showed an increase in hydrophobicity in PLA-collagen-drug samples. The antibacterial studies showed a high efficacy of resistance against the growth of both E. coli and S. Aureus, except with PLA-collagen-LEVO which showed a regrowth of bacteria after 48h. This can be attributed to the low drug release percentage incorporated into the nanofibre during the in vitro release study. However, the studies did show that collagen helped shift both drugs into sustained release behaviour. These ideal modifications to electrospun scaffolds may prove useful in further research regarding the acceptance of human tissue by inhibiting the potential for bacterial infection.

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Viral diseases remain a major cause of death worldwide. Despite advances in vaccine and antiviral drug technology, each year over three million people die from a range of viral infections. Predominant viruses include human immunodeficiency virus, hepatitis viruses, and gastrointestinal and respiratory viruses. Now more than ever, robust, easily mobilised and cost-effective antiviral strategies are needed to combat both known and emerging disease threats. RNA interference and small interfering (si)RNAs were initially hailed as a "magic bullet", due to their ability to inhibit the synthesis of any protein via the degradation of its complementary messenger RNA sequence. Of particular interest was the potential for attenuating viral mRNAs contributing to the pathogenesis of disease that were not able to be targeted by vaccines or antiviral drugs. However, it was soon discovered that delivery of active siRNA molecules to the infection site in vivo was considerably more difficult than anticipated, due to a number of physiological barriers in the body. This spurred a new wave of investigation into nucleic acid delivery vehicles which could facilitate safe, targeted and effective administration of the siRNA as therapy. Amongst these, cationic polymer delivery vehicles have emerged as a promising candidate as they are low-cost and easy to produce at an industrial scale, and bind to the siRNA by non-specific electrostatic interactions. These nanoparticles (NPs) can be functionally designed to target the infection site, improve uptake in infected cells, release the siRNA inside the endosome and facilitate delivery into the cell cytoplasm. They may also have the added benefit of acting as adjuvants. This chapter provides a background around problems associated with the translation of siRNA as antiviral treatments, reviews the progress made in nucleic acid therapeutics and discusses current methods and progress in overcoming these challenges. It also addresses the importance of combining physicochemical characterisation of the NPs with in vitro and in vivo data.

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The objective of the study was to determine the effects of pomegranate seed oil, used as a source of punicic acid (CLnA) in the diets of laying hens, on the physicochemical properties of eggs. Forty Isa Brown laying hens (26weeks old) were equally subjected to 4 dietary treatments (n=10) and fed a commercial layer diet supplying 2.5% sunflower oil (control) or three levels (0.5, 1.0 and 1.5%) of punicic acid in the diets. After 12weeks of feeding the hens, eggs collection began. Sixty eggs - randomly selected from each group - were analysed for physicochemical properties. Eggs naturally enriched with CLnA preserve their composition and conventional properties in most of the analysed parameters (including chemical composition, physical as well as organoleptic properties). Dietary CLnA had positive impact on the colour of the eggs' yolk, whereas the hardness of hard-boiled egg yolks was not affected. Additionally, increasing dietary CLnA led to an increase not only the CLnA concentrations, but also CLA in egg-yolk lipids.

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