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Since the 1980's when the predominate focus of study and use of carotenoids in human nutritional formulations was solely on beta-carotene, there has been a steady increase in research aimed to understand the role of a wide variety of carotenoids in human health. This work has increasingly demonstrated the benefits of a number of carotenoids, and there has been a corresponding increase in the number of carotenoids provided in nutritional supplements (multicarotenoids). Numerous published observations in both human and animal studies suggest significant interaction and competition between various carotenoids during absorption and metabolism, resulting in the inhibition of uptake of one over the other. This competition has the end result of reducing the beneficial effects of the inhibited carotenoid. To limit such competition and maximize carotenoid uptakes, a layered beadlet was designed to release a defined ratio of carotenoids sequentially. Preliminary dissolution testing is presented showing the release profile in simulated digestive conditions of a combination of beta-carotene, alpha carotene, lutein, zeaxanthin, lycopene and astaxanthin derived from natural sources. Comparison is made to an immediate release beadlet formulation using the same combination of carotenoids. These results will be used to guide proof of concept clinical testing for effectiveness in humans.
EN
An indomethacin topical spray was prepared using lecithin and a cholesterol derivative as a phospholipid complex in a film. Polyvinylpyrrolidone (PVP) was used as a film-forming agent. Drug penetration through keratinocytes was evaluated as well as cytotoxicity to the keratinocytes and fibroblast cells. The results reveal that the PVP concentration provided fine droplets under a microscope with a low contact angle (12.07°-22.53°). Incorporating PVP in the formulation reduced the hydrodynamic radius or size by 20 times. The SEM and TEM results showed smoother surfaces of the thin film for larger quantities of the PVP film-forming agent in the formulations. It also gave the highest drug penetration when the PVP was 0.5%. However, the film-forming agent can also act as a control release barrier. The percent viabilities of the human keratinocytes and fibroblasts were higher in the indomethacin spray phospholipid complex thin film formulation than the pure drug.
EN
In view of ongoing interest in biodegradable polymers, dibutyrylchitin was used as a matrix for controlled release of a model substance. Transdermal systems (films) are presently more commonly used as an alternative to standard forms of drug delivery. The presented results are concerned with the release of ibuprofen from dibutyrylchitin film. The obtained transdermal films were modified by applying a control layer to slow down the release process. The matrices were also modified by adding nanoclay (Nanofil 2). Dibutyrylchitin matrices were tested for swelling and release kinetics using UV-Vis spectrophotometer. The drug kinetics release was studied in phosphorus buffer of pH=5.5 at the temperature of 35˚C. Structural investigations of the obtained matrices were carried out by optical microscopy and FTIR spectrophotometry. An appropriate mathematical model was also fitted to the obtained experimental data
EN
Nanoagrochemicals, such as nanopesticides, nanofertilizers or plant growth stimulating nanosystems, were primarily designed to increase solubility, enhance bioavailability, targeted delivery, controlled release and/or protection against degradation resulting in the reduced amount of applied active ingredients and finally in a decrease of dose-dependent toxicity/burden. This paper is a comprehensive up-to-date review related to the preparation and the biological activity of nanoformulations enabling gradual release of active ingredient into weeds and the body of pests and controlled release of nutrients to plants. The attention is also devoted to the decrease of direct environmental burden and economic benefits due to application of nanoformulations, where less amount of active ingredient is needed to achieve the same biological effect in comparison with bulk. The application of nanotechnology in the areas such as food packaging, food security, encapsulation of nutrients and development of new functional products is analysed. The use of nanoparticles in biosensors for detection of pathogens and contaminants as well as in DNA and gene delivery is discussed as well. Benefits and health risks of nanoagrochemicals are highlighted, and special attention is given to nanoecotoxicology and guidelines and regulatory documents related to the use of nanoformulations in agriculture and food industry.
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