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Current methods for the study of pigments involve freezing in liquid nitrogen and storage at -80 degrees C or lyophilization until HPLC analysis. These requirements greatly restrict ecophysiological research in remote areas where such resources are hardly available. We aimed to overcome such limitations by developing several techniques not requiring freezing or lyophilization. Two species with contrasting foliar characteristics (Olea europaea and Taraxacum officinale) were chosen. Seven preservation methods were designed, optimized and tested in a field trial. These protocols were compared with a control immediately frozen after collection. Pigments and tocopherols were analysed by HPLC. Main artefacts were chlorophyll epimerization or phaeophytinization, carotenoid isomerization, altered de-epoxidation index and tocopherol degradation. Among all methods, sample desiccation in silica gel provides robust samples (pigment composition was unaffected by storage time or temperature) and almost unaltered pigment profiles, except for a shift in epoxidation state. Although liquid nitrogen freezing and subsequent lyophilization or freezer storage were preferred, when these facilities are either not available or not suitable for long-distance transport, desiccation with silica gel, passive extraction in acetone and/or storage of fresh samples in water vapour saturated atmospheres enable a complete pigment characterization. Silica gel is advisable for long-term sample conservation.
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http://dx.doi.org/10.1007/s11120-009-9468-5 | DOI Listing |
Mikrochim Acta
September 2025
Affordable and Sustainable Sample Preparation (AS2P) Research Group, Departamento de Química Analítica, Instituto Químico para la Energía y el Medioambiente IQUEMA, Universidad de Córdoba, Campus Universitario de Rabanales, Edificio Marie Curie, E-14071, Córdoba, Spain.
Stainless-steel substrates have grown in importance in the development of planar sorptive phases. However, the reduced wettability of polished sheets makes difficult their functionalization. This limitation can be solved by using amorphous silica gel microparticles as superficial guides.
View Article and Find Full Text PDFDrug Dev Res
September 2025
Department of Pharmaceutics, School of Pharmacy, Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu Provincial Research Center for Medicinal Function Development of New Food Resources, Jiangsu University, Zhenjiang, Jiangsu, China.
Liver cancer is the fourth most deadly cancer worldwide, but existing treatment options are insufficient, thus highlighting the urgent need for new therapeutic agents. Taxanes, known for their anticancer properties, provide a promising avenue for intervention. In this study, a tetracyclic taxane compound with antitumor activity (taxinine) was extracted and isolated from Taxus chinensis (T.
View Article and Find Full Text PDFFront Bioeng Biotechnol
August 2025
Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou, Guangdong, China.
Introduction: During the healing process, the functional gradient attachment of the rotator cuff (RC) tendon-bone interface fails to regenerate, which severely impedes load transfer and stress dissipation, thereby increasing the risk of retears. As a result, the treatment of rotator cuff tears remains a significant clinical challenge.
Methods: In this study, a dual-crosslinked hyaluronic acid/polyethylene glycol (HA/PEG) hydrogel scaffold was synthesized using hyaluronic acid and polyethylene glycol as base materials.
Soft Matter
September 2025
Nestlé Product Technology Centre, York, YO31 8FY, UK.
Particles with some degree of hydrophilicity are known to aggregate when directly dispersed in non-aqueous media. Proteins are generally insoluble in oil and have complex surface properties, but they may form networks in oil like more simple colloidal particles, depending on particle size and surface hydrophilicity. Here, the particle size of pea protein isolate (PPI) particles in oil was reduced to submicron sizes by stirred media milling.
View Article and Find Full Text PDFJ Dent
September 2025
Department of Restorative Dentistry, Faculty of Dentistry, Malaya University, Kuala Lumpur, Malaysia. Electronic address:
Objectives: to evaluate the effect of smear-layer deproteinization using papain gel and SPRG-adhesive on marginal-gap, anti-demineralization of enamel and dentin after chemical pH cycling and assess acid-base resistance zone (ABRZ) characteristics.
Methods: Cylindrical cavities were prepared cervically in thirty-two extracted premolars. Teeth were divided into two pretreatment groups (n=16); deproteinization with papain enzyme gel (Papacarie Due, Brazil) for 60 second, and no-deproteinization.