Vpliv stresa na pojav in potek kožnih bolezni : univerzitetni študijski program Kozmetologija

Oblak, Iza (author), Jeras, Matjaž (mentor)

Na uporabnost in varnost kozmetičnih izdelkov pomembno vpliva njihova stabilnost, ki mora biti zagotovljena skozi celoten rok uporabe, med shranjevanjem in transportom le-tega od proizvajalca do potrošnika. S pomočjo stabilnostnih študij zagotavljamo njihovo fizikalno, kemijsko in mikrobiološko kakovost, funkcionalnost in estetske lastnosti pri normalnih pogojih shranjevanja. Zaradi raznolikosti in kompleksnosti kozmetičnih izdelkov ni na voljo standardnih testov. Proizvajalec jih mora praviloma, po lastni strokovni presoji in ob upoštevanju značilnosti izdelkov, načrtovati sam. Fizikalna nestabilnost povzroča težave med načrtovanjem in izdelavo kozmetičnih izdelkov, kot tudi med transportom, shranjevanjem in uporabo le-teh. Vzrok zanjo so lahko različni dejavniki, kot so neustrezno načrtovanje, proizvodnja, distribucija, uporaba in neprimerno shranjevanje izdelka. V okviru diplomske naloge smo uporabili metodo za pospešeno testiranje fizikalne stabilnosti grobo disperznih sistemov z uporabo mehanskih vibracij, ki bi lahko v krajšem času pokazala znake nestabilnosti izdelka ter tako zmanjšala obseg nadaljnjih testiranj. Testirali smo emulzijske sisteme izbranih izdelkov podjetja Ilirija d.o.o. Stresnim pogojem vibriranja smo izpostavili stabilne in nestabilne formulacije enakih izdelkov, ki so jih v podjetju predhodno sicer že testirali s pomočjo pospešenih in dolgoročnih testiranj. Metoda se je izkazala kot primerna, saj smo po šesturnem vibracijskem stresanju pri 25 °C in amplitudi 80% (nastavitve na vibratorju) z rotacijsko viskozimetrijo in polarizacijsko mikroskopijo dobili primerljive rezultate že obstoječim rezultatom testiranja v Ilirija d.o.o. Stereomikroskopija, oscilatorno testiranje in organoleptično vrednotenje so se kot testne metode v tem primeru izkazale za neustrezne, saj niso dale dovolj natančnih oziroma enotnih in reprezentativnih podatkov. Vzorcev nismo izpostavili stresanju pri povišani temperaturi (temperaturni komori), saj smo s pomočjo diferenčne dinamične kalorimetrije (DSC) ugotovili, da se pri dvigu temperature na okrog 40 °C sistemi že ireverzibilno spremenijo. Načrtovano testiranje pri zvišani temperaturi bi zato lahko uporabili za stabilnostno testiranje le takšnih disperznih sistemov, katerih komponente se pri teh temperaturah fizikalno ne spreminjajo.

• Language: Slovenian
• Keywords: stres, koža kožne bolezni nega kože
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FFA - Faculty of Pharmacy
• Place of publishing: Ljubljana
• Publisher: [I. Oblak]
• Year: 2018
• Number of pages: 43 f.
• PID: 20.500.12556/RUL-120144
• UDC: 613.86:616.5(043.2)
• COBISS.SI-ID: 4571249
• Publication date in RUL: 16.09.2020

Secondary language

• Language: English
• Title: Influence of stress on the onset and course of skin diseases

Abstract

The usage and safety of cosmetic products are significantly influenced by their stability, which must be ensured throughout the entire shelf life, during storage and transport from the manufacturer to the consumer. With stability studies we ensure their physical, chemical and microbiological quality, functionality and aesthetic properties under normal storage conditions. Because of diversity and complexity of cosmetics, standard tests are not available. The manufacturer has to design them himself, with consideration of products characteristics and his professional judgment. Physical instability often causes problems during design development and manufacture of cosmetics, as well as during the transport, storage and their usage. The causes can be various factors, such as unsuitable design development, manufacturing design, distribution, usage and inappropriate storage of the product. In the diploma thesis, we used a method for accelerated stability testing of disperse systems physical stability by application of mechanical vibrations, which could show signs of instability in a short period of time and could also reduce the scope of further testing. We tested the emulsion systems of selected products, manufactured by the company Ilirija d.o.o. Stable and unstable formulations of the same products, which had already been tested with different accelerated and long-term tests by the company, were put under stressful vibrating conditions. After 6 hours of exposure to mechanical vibrations at 25 °C and the amplitude of 80%, comparable results were obtained with rotational testing and polarization microscopy, therefore the method proved to be suitable. Stereomicroscopy, oscillatory testing and organoleptic evaluation have proved to be unsuitable as test methods in this case, because the obtained data was not uniform and representative enough. Samples were not exposed to vibrations in the heat chamber, as they were found to be hypersensitive to elevated temperatures, such as 40 °C, by means of differential dynamic calorimetry (DSC). Testing could be used for the stability testing of only such disperse systems whose components do not physically change at elevated temperatures.

• Keywords: stability testing physical stability mechanical vibration rheology polarized optical microscopy