Joanna Znaleziona

A novel positively charged surfactant N‐dodecyl‐N,N‐dimethyl‐(1,2‐propandiol) ammonium chloride was used for the dynamic coating of the inner wall of a silica capillary. This paper covers the evaluation of dynamic coating and study of the influence of the analysis conditions for the magnitude and direction of electroosmotic flow as well as for the effective and selective separation of chosen proteins (ribonuclease A, cytochrome c, lysozyme, and myoglobin). The concentration of 0.1 mM of N‐dodecyl‐N,N‐dimethyl‐(1,2‐propandiol) ammonium chloride enabled the reversal of the electro‐osmotic flow, however, to separate basic as well as neutral proteins the higher concentration of the studied surfactant was necessary. The final conditions for the separation of studied proteins were set at 100 mM sodium acetate pH 5.5 with 10.0 mM of the studied surfactant. The results were also compared with those of two commercially available cationic surfactants, cetyltrimethylammonium bromide and dodecyltrimethylammonium bromide. Additionally, the developed method for protein separation was applied for the determination of lysozyme in a cheese sample. The limits of detection and quantification of lysozyme were 0.9 and 3.0 mg/L, respectively. The mean concentration of lysozyme found in the cheese sample was 167.3 ± 10.3 mg/kg.

A dynamic coating using polyamidoamine (PAMAM) dendrimers was used to change the direction and magnitude of electroosmotic flow. The influence of PAMAM on electroosmotic mobility was studied in the concentration range from 0.005 to 0.100% (w/v) and at different electrolyte pH values from 2.5 to 8.5. PAMAM dendrimers, as an additive to the background electrolyte, were able to reverse the electroosmotic flow at a low concentration level (0.01% w/v). The presented dynamic coating was then applied to the enantioseparation of selected amines such as R,S- and S,R-tapentadol, R- and S-isoproterenol and R,S- and S,R-ephedrine with the use of 2-hydroxypropyl-β-cyclodextrin as the chiral selector.

The capillary zone electrophoresis method was developed for the chiral separation of

A new method for the determination of anti‐diabetic drugs metformin and rosiglitazone based on the use of capillary electrophoresis with electrospray mass spectrometry was developed. The proposed method allowed their separation within 11 min by using 50 mM formic acid at +20 kV. Positive electrospray ionization and selected ion monitoring [M+H]⁺ of metformin (m/z=130) and rosiglitazone (m/z=358) were performed. Several important experimental parameters influencing electrospray ionization of metformin and rosiglitazone were studied. The final composition of sheath liquid was water/methanol/formic acid (50:49.5:0.5, v/v/v), at a flow rate of 2 μL/min. The developed method was applied for the determination of metformin and rosiglitazone simultaneously in human serum after protein precipitation with acetonitrile. The limits of detection of developed method were 4.42 and 2.14 ng/mL for rosiglitazone and for metformin, respectively, which is sufficient for therapeutic serum concentration levels monitoring for both studied drugs.

The capability to present electronic media that can preserve information is highly restricted to few decades (e.g., a lifetime of DVD media does not exceed 100 years), and therefore the question of how to preserve documents for more than thousands or millions of years presents a challenging task. In this article, we discuss three thinkable possibilities for long-term data storage: (i) self-assembly systems, (ii) chirality, and (iii) nucleic acids. These systems have, in our opinion, added-value regarding functionality and storing capability. Self-assembly systems form 3D structures, which could reflect any information more precisely than a 2D structure, and therefore they could be used as a training information package. Chirality provides the next added value in the possibility of using an interval of for storing the data (fuzzy logic) and could be also interesting in increasing the storage capacity if using compounds with more chiral centers, such as polysaccharides. Finally, nucleic acids represent a method of storage in which the reading step is developed and probably will be still active if people inhabit the Earth, which will realize the whole process of writing/storing and reading easier.