Review: Recent advancements and moving trends in chemical analysis of fire debris.

This review describes recent advances and current trends in fire debris analysis from 2014 to 2021. Onsite analytical techniques used for fire scene investigation, identifying samples of interest for later analysis as well as onsite confirmatory techniques are examined. Laboratory techniques are reviewed both from a perspective of instrumentation and data analysis.

Rapid screening of phenolic compounds in extracts of photosynthetic organisms separated using a C18 monolithic column based HPLC-UV method.

The sourcing of novel bioactive compounds from bioresources has become a sustainability priority for several industrial sectors. Reliable methods are hence needed for the screening and identification of desired molecules in complex extracts. As such, phenolic compounds have attracted increasing interests due to their antioxidant potential.

Antioxidant Activity and Carotenoid Content Responses of Three Haematococcus sp. (Chlorophyta) Strains Exposed to Multiple Stressors.

There has been increasing demands worldwide for bioactive compounds of natural origins, especially for the nutraceutical and food-supplement sectors. In this context, microalgae are viewed as sustainable sources of molecules with an array of health benefits. For instance, astaxanthin is a xanthophyll pigment with powerful antioxidant capacity produced by microalgae such as the chlorophyte Haematococcus sp.

Differential responses in EPA and fucoxanthin production by the marine diatom Stauroneis sp. under varying cultivation conditions.

There has been an increasing drive toward better valorising raw biological materials in the context of the sustainability of bio-based industries and the circular economy. As such, microalgae hold the ability to biosynthesise valuable metabolites, which are sought after within the bioenergy, pharmaceuticals, cosmetics or nutrition sectors. Owing to their bioactivities, the xanthophyll pigment fucoxanthin and the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) have fostered increasing interests in terms of sustainably refining them from natural sources, such as microalgae.

Antioxidant Bioprospecting in Microalgae: Characterisation of the Potential of Two Marine Heterokonts from Irish Waters.

Microalgae constitute a heterogeneous and diverse range of organisms capable of accumulating bioactive metabolites, making them promising feedstock for applications in the nutraceutical, functional food, animal feed, biofertilisation or biofuel sectors. There has been renewed interest in recent times in natural sources of antioxidants, particularly as health products and preserving agents. Microalgae strains isolated from aquatic habitats in Ireland were successfully brought into culture.

Influence of spectral intensity and quality of LED lighting on photoacclimation, carbon allocation and high-value pigments in microalgae.

Tailoring spectral quality during microalgal cultivation can provide a means to increase productivity and enhance biomass composition for downstream biorefinery. Five microalgae strains from three distinct lineages were cultivated under varying spectral intensities and qualities to establish their effects on pigments and carbon allocation. Light intensity significantly impacted pigment yields and carbon allocation in all strains, while the effects of spectral quality were mostly species-specific.

Fabrication and characterisation of capillary polymeric monoliths incorporating continuous stationary phase gradients.

Polymeric monoliths in capillary formats have been fabricated incorporating a gradient of charged functional groups along their length. Scanning capacitively coupled contactless conductivity detection (sC(4)D) was then used to measure the conductive response of the stationary phase and characterise the relative axial distribution of functional groups along the column length. Gradients of 2-acrylamido-2-methyl-1-propanesulphonic acid were prepared using either photografting methods or by filling a capillary column with segmented plugs of monomer mixtures each containing incrementally higher concentrations of the functional monomer.

On-column titration and investigation of metal complex formation for aminopolycarboxylate functionalised monoliths using scanning contactless conductivity detection.

The application of scanning capacitively coupled contactless conductivity detection (SC(4)D) for the determination of pH dependant behaviour of two aminopolycarboxylates immobilised onto the surface of a monolithic capillary column is described. The use of SC(4)D to visualise changes in conductivity of the discrete zones of functional groups within monolithic capillary columns allows for the effects of immobilisation on the physicochemical properties of zones to be compared to that of the functional group in solution. The perturbation of the pK(a) values of the functional groups can be attributed to the change in chemical environment experienced by the functional group through the presence of local hydrogen bonding and surface induced effects.

Using scanning contactless conductivity to optimise photografting procedures and capacity in the production of polymer ion-exchange monoliths.

Capacitively coupled contactless conductivity detection (C4D) is utilised as a simple, rapid and non-invasive technique for the quantitative evaluation of the ion-exchange capacity of charged polymer monoliths in capillary format. A charged monomer, 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) was photografted onto a 100 microm i.d.

Development of a contactless conductivity detector cell for 1.6 mm O.D. (1/16th inch) HPLC tubing and micro-bore columns with on-column detection.

A capacitively coupled contactless conductivity detector cell was designed and constructed suitable for standard HPLC 1.6 mm o.d.

Accurate non-invasive determination of pKa of surface functionalised ion exchange monoliths using capacitively coupled contactless conductivity detection.

The use of on-column capacitively coupled contactless conductivity detection for the accurate non-invasive visualisation of the pH dependence of covalently bound boronic acid groups within a monolithic polymeric capillary column is demonstrated.

Use of contactless conductivity detection for non-invasive characterisation of monolithic stationary-phase coatings for application in capillary ion chromatography.

A capacitively-coupled contactless conductivity detector (C4D) has been utilised as an on-capillary detector within a capillary ion chromatograph, incorporating a reversed-phase monolithic silica capillary column semi-permanently modified with a suitable ionic surfactant. The monolithic capillary column (150 x 0.1 mm i.

Capillary ion chromatography of inorganic anions on octadecyl silica monolith modified with an amphoteric surfactant.

A reversed-phase monolithic silica based capillary column (Onyx C(18), 150 mm x 0.1 mm) was modified with the amphoteric surfactant, N-dodecyl-N,N-(dimethylammonio)undecanoate (DDMAU) and evaluated for the separation and determination of inorganic anions using on-column capacitively coupled contactless conductivity detection (C(4)D). The chromatographic performance of the column was evaluated and under optimal conditions separation efficiencies of 56,200 plates per meter or 7025 plates per column (at detection point) were observed (for iodide).

Evaluation of capillary ion exchange stationary phase coating distribution and stability using radial capillary column contactless conductivity detection.

The use of radial (across) capillary column capacitively coupled contactless conductivity detection is demonstrated as a simple and rapid technique for visualisation of stationary phase longitudinal coverage and coating stability in capillary ion exchange chromatography.