In order to increase the longevity of the documents, written by iron gall inks, stabilisation treatments have been developed during the last two decades. Their effectiveness has often been determined by comparing rates of degradation during accelerated tests. However, such evaluation using historical materials is limited by the amount of material required by various analytical methodologies. The paper describes the use of size exclusion chromatography (SEC) of cellulose containing iron gall ink, derivatised using phenyl isocyanate. A linear correlation is observed between the weight average degree of polymerisation obtained with SEC and the one obtained using viscometry. The method was used to evaluate the extent of stabilisation of historic documents containing iron gall inks during accelerated degradation.
F.02 Acquisition of new scientific knowledge
COBISS.SI-ID: 36309253LC-MS/MS method with SPE for rutin, quercetin, hesperidin, hesperetin and kaempferol determination in food samples was developed and matrix effect evaluated using a postextraction addition method: –44 to –0.5%, indicating ionization suppression and explained by co-elution of phenolic acids. Recoveries of flavonoids were 88–96%. Sample extracts were analyzed by LC–MS/MS in SRM mode using the most suitable calibration - standard addition method. The results (mg/100 g fresh weight) were for rutin 0.16; quercetin 0.65–56; hesperidin 0.016–24; hesperetin 0.0068–36.4 and kaempferol 0.14–1.63 and show good agreement with published data. Low LODs (0.014–0.063 ug/mL) were obtained.
F.02 Acquisition of new scientific knowledge
COBISS.SI-ID: 36369157Ion-exclusion chromatography (IEC) is a type of liquid chromatography that was first introduced by Wheaton and Bauman in 1953. The theory supporting the basic observations was not changed since recently, when it was radically renewed. In opposite to the clasical theory, the recently introduced theory was successfully used for the explanation of some phenomena, for which the original theory wasn’t successful. Some of these phenomena, described in this book chapter, are peak shapes in IEC, simultaneous separation of anions and cations in IEC (acid rain) and indirect UV-Vis detection in IEC
F.02 Acquisition of new scientific knowledge
COBISS.SI-ID: 36290053