Evaluation of Biologically Active Compounds from Calendula officinalis Flowers using Spectrophotometry

<p>Abstract</p> <p>Background</p> <p>This study aimed to quantify the active biological compounds in <it>C. officinalis </it>flowers. Based on the active principles and biological properties of marigolds flowers reported in the literature, we sought to obtain and characterize the molecular composition of extracts prepared using different solvents. The antioxidant capacities of extracts were assessed by using spectrophotometry to measure both absorbance of the colorimetric free radical scavenger 2,2-diphenyl-1-picrylhydrazyl (DPPH) as well as the total antioxidant potential, using the ferric reducing power (FRAP) assay.</p> <p>Results</p> <p>Spectrophotometric assays in the ultraviolet-visible (UV-VIS) region enabled identification and characterization of the full range of phenolic and flavonoids acids, and high-performance liquid chromatography (HPLC) was used to identify and quantify phenolic compounds (depending on the method of extraction). Methanol ensured more efficient extraction of flavonoids than the other solvents tested.</p> <p>Antioxidant activity in methanolic extracts was correlated with the polyphenol content.</p> <p>Conclusions</p> <p>The UV-VIS spectra of assimilator pigments (e.g. chlorophylls), polyphenols and flavonoids extracted from the <it>C. officinalis </it>flowers consisted in quantitative evaluation of compounds which absorb to wavelengths broader than 360 nm.</p

Effect of carbon nanofibre structure on the binding of antibodies

Potential biomedical applications for carbon nanofibres include, but are not limited to, biosensors and drug delivery vehicles. For such applications, it is essential to know how carbon nanotubes interact with antibodies and proteins. We report on the successful adsorption of monoclonal CD3 antibodies on two types of carbon nanofibre produced by the same method and having the same average size and shape, but differing in surface structure and chemistry due to dissimilar post-treatments. Binding of proteins to nanofibres is enhanced by poly (L-lysine) (PLL) and improves with increasing disorder and hydrophilicity of the nanofibres' surface. Oxidized and disordered surfaces of pyrolytically stripped nanofibres show improved wetting and attachment of PLL and proteins compared to hydrophobic and well-ordered surfaces of heat-treated nanofibres. These results show that the surface of carbon nanofibres can be tailored for their use in biomedical applications

Effect of carbon nanofibre structure on the binding of antibodies

Potential biomedical applications for carbon nanofibres include, but are not limited to, biosensors and drug delivery vehicles. For such applications, it is essential to know how carbon nanotubes interact with antibodies and proteins. We report on the successful adsorption of monoclonal CD3 antibodies on two types of carbon nanofibre produced by the same method and having the same average size and shape, but differing in surface structure and chemistry due to dissimilar post-treatments. Binding of proteins to nanofibres is enhanced by poly (L-lysine) (PLL) and improves with increasing disorder and hydrophilicity of the nanofibres' surface. Oxidized and disordered surfaces of pyrolytically stripped nanofibres show improved wetting and attachment of PLL and proteins compared to hydrophobic and well-ordered surfaces of heat-treated nanofibres. These results show that the surface of carbon nanofibres can be tailored for their use in biomedical applications