Determination of Apigenin in Cosmetics Containing Chamomile by High-Performance Liquid Chromatography with Ultraviolet Detection (HPLC-UV)

© 2022 Taylor & Francis Group, LLC.A simple, rapid, and precise high performance liquid chromatography (HPLC) method was developed to determine the flavonoid apigenin in cosmetic products containing chamomile extracts. A C18 column was used as stationary phase and 70:30 ethanol:water was used as mobile phase with a 1 mL/min flow rate and isocratic elution. The temperature was stabilized at 25 °C during the separation. The injection volume was 50 μL. The apigenin peak was eluted at 4.15 ± 0.4 min. The method was validated according to International Conference on Harmonisation (ICH) criteria in terms of linearity, limit of detection, limit of quantitation, selectivity, sensitivity, robustness, accuracy, and precision. The limits of detection and quantitation were 0.060 and 0.2 μg/mL respectively. The linear range was from 0.2 to 20 μg/mL. The relative standard deviation values for intraday and interday analyses were less than 1.64%. The developed procedure was applied to the analysis of various cosmetic products. It is expected that the method is suitable for routine analysis, quality control and standardization of cosmetic products for apigenin

Melatonin deficiency at tissue level: a possible aetiological factor in nasal polyposis

Objective The aim of this study was to examine whether melatonin is involved in the pathogenesis of nasal polyposis. Method This study included 29 patients with nasal polyposis and undergoing functional endoscopic sinus surgery. As a control group, 26 patients who had been operated on for a deviated nasal septum and concha bullosa were enrolled. Samples were taken from the nasal polyp tissue and from the resected middle concha bullosa mucosa of the control group. Serum samples were taken from all patients. Results It was found that the tissue and serum melatonin levels in the nasal polyp group were significantly lower compared with the tissue and serum melatonin levels in the control group. Conclusion In nasal polyposis, the melatonin level in the serum and tissue is lower than in individuals without polyposis. This deficiency may play a role in the pathogenesis of nasal polyposis.Bezmialem Vakif UniversityBezmialem Vakif UniversityThis research was supported by Bezmialem Vakif University

Water-soluble trace, rare earth elements and organic compounds in Arctic aerosol

We investigated the elemental composition and water-soluble-organic compounds (WSOC) present in size-segregated airborne particulate matter to better understand: (1) the distribution of the water-soluble fraction of trace elements (TE), rare earth elements (REE) and WSOCs among different particulate sizes, and (2) the transport processes of aerosol towards the Arctic zone. Samples were collected at Ny-Alesund in the Svalbard Islands (78A degrees 55'07aEuro(3)N, 11A degrees 53'30aEuro(3)E) from 19 April to 14 September 2010. Water-soluble TE and REE were measured with the aim of recognising reliable tracers of specific sources, which may prove crucial in cost-effective strategies of air pollution control. The TE and REE content, especially in the finest fractions of aerosols in remote areas, is primarily due to long-range transport. It gives valuable information on the global circulation and on the contribution of human activities to aerosol composition (Birmili et al. in Environ Sci Technol 40:1144-1153, 2006; Fernandez-Espinosa et al. in Atmos Environ 38:873-886, 2004; Song et al. in Atmos Environ 35:5277-5286, 2001). On the same samples, we also determined water-soluble organic tracers as specific source indicators: levoglucosan and methoxyphenols from biomass burning, acrylamide from anthropogenic origin and amino acids from primary production. These results were discussed in previous papers (Scalabrin et al. in Atmos Chem Phys 12:10453-10463, 2012; Zangrando et al. in Environ Sci Technol 47:8565-8574, 2013)