Journal of Analytical Techniques and Research
Latest articles in this journal
Journal of Analytical Techniques and Research, Volume 03, pp 28-38; https://doi.org/10.26502/jatri.020
The results of the theory of modeling for obtaining nanocylinders have been described. A case of a nanocylinder whose diameters are shorter than the Tolman length has been considered. This important issue is taken into account in studying a nanocylinder for which, in the simplest model, the thickness of the interfacial layer cannot be determined because it supposedly has a small size. At the same time, it has been shown that the introduction of a special form of anisotropy energy makes it possible to analytically describe the origin of an interfacial layer whose sizes can be regarded as sizes comparable to the Tolman length.
Journal of Analytical Techniques and Research, Volume 03; https://doi.org/10.26502/jatri.022
Journal of Analytical Techniques and Research, Volume 03, pp 14-27; https://doi.org/10.26502/jatri.019
In this study, the applicability of the adaptive neuro-fuzzy inference system (ANFIS) and response surface methodology (RSM) was evaluated to forecasting the supercritical extraction of St. John’s Wort. In this case, the ANFIS model was optimized by the firefly algorithm (FFA) to develop the performance of the model. The accuracy of the models was investigated by comparing the result of the models with experimental data. The precision of the RSM model has been investigated using statistical analysis (P-value<0.05, F-value=148.13, R2=0,99 R2 Adjusted=0.98, R2 Predicted =0.96). The data transfer power was proved by the Box-Cox plot. Also, the polynomial model shows that it is much simpler and easier than other complex models. The results show, the ANFIS-FFA with R2=0.99, RMSE=1.79 and AARD%=2.79 have a high capability of predicting the St. John’s Wort extraction amount
Journal of Analytical Techniques and Research, Volume 03, pp 39-45; https://doi.org/10.26502/jatri.021
The theory of surface phenomena in the production of micro- and nanocylinder for important cases is considered. The case of a nanocylinder is considered, when its diameter is greater than, equal to, or less than Tolman's length. We found a correspondence between the Gibbs – Tolman – Konig – Buff and linear Van der Waals theories. But for a nonlinear theory, this correspondence is absent.
Journal of Analytical Techniques and Research, Volume 03, pp 1-13; https://doi.org/10.26502/jatri.018
Coconut water (CW) has gained wide attraction as a known functional food that offers additional benefits to its basic nutritional value. CW is employed in the management of oxidative stress-associated diseases for its natural antioxidant features. This study sought to investigate CW antioxidant capacity and effect upon its dietary inclusion in an Alcl3-induced amnesic Drosophila melanogaster. CW was extracted from the coconut fruit cotyledon and supplemented in the flies’ diet for five days. The CW extract antioxidant activity was examined in vitro through the total phenol, total flavonoid content, ferric reducing power, iron-chelating ability, ABTS* and DPPH* scavenging ability assays. Likewise, the anti-lipid peroxidation potential of CW extract was also measured in vivo using D. melanogaster. The CW extract has a total phenol content of 1.48 ± 0.43 (mg/g GAE) and a total flavonoid content of 0.53 ± 0.02 (mg/g QE) which could be attributed to its scavenging ability against ABTS* and DPPH* in vitro with an increase in extract concentration. Similarly, a positive trend was detected in the ferric reducing antioxidant power and iron-chelating ability tests. Furthermore, dietary inclusion of CW in groups fed with 0.1% and 1% CW lowers Malondialdehyde (MDA) concentration significantly (p < 0.01 and p < 0.0001 respectively) in Alcl3 induced flies. This correlates with CW’s ability to considerably (p < 0.05) reduced MDA in vitro in a concentration-dependent manner (0.01 – 0.03 mg/mL). These findings provide substantial information that affirms CW's natural antioxidant ability, thus bolstering its therapeutics usage.
Journal of Analytical Techniques and Research, Volume 2, pp 96-109; https://doi.org/10.26502/jatri.014
Resveratrol is a polyphenol derived from a variety of food and beverages, which has been reported to possess diverse pharmacological activities. An ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) method was established to figure out the metabolic profiles of resveratrol in rat biological samples after oral administration. According to the results, 21 resveratrol-related metabolites in rat biosamples were found after oral administration. As far as we know, 14 of these metabolites (M3 to M10, M13, M16, M17 and M21) have not been reported previously. Furthermore, glucuronide conjugation, sulfate conjugation, methylation, hydroxylation and reduction were the main metabolic pathways. Besides, the hydroxylated product was also detected in rat liver microsome. The results may be conducive to a better understanding the metabolic mechanism of resveratrol and provide helpful chemical information for further pharmacological and action mechanism studies of resveratrol.
Journal of Analytical Techniques and Research, Volume 2, pp 123-136; https://doi.org/10.26502/jatri.016
There exists much interest in identifying and quantitating oxidized lipids in biofluids and tissues because certain oxidized lipids may potentially serve as early-stage diagnostic biomarkers of disease states such as preeclampsia. To that end, a set of seven biologically relevant oxidized lipids (lipid aldehydes) have been studied in placental tissue. A novel method for analyzing these seven target biologically relevant oxidized lipids was developed and is presented. Placental samples processed and analyzed by LC-MS/MS for the content of the seven specified lipid aldehydes. Additionally, the placental samples were profiled for additional (untargeted) lipid aldehydes. The LC-MS/MS method was qualified and found to have acceptable linearity, accuracy and precision for its intended use. It was determined that placental tissue from mothers with preeclampsia had relatively lower amounts of oxidized lipids when compared to control placental tissue.
Journal of Analytical Techniques and Research, Volume 2, pp 18-26; https://doi.org/10.26502/jatri.010
The implication of social capital to people’s economic position has not been well addressed in Ethiopia. Thus, this study is aimed to examine the effect of household’s stock of social capital on its economic wellbeing, taking a random sample of households from Jimma zone. To objective this objective, we obtained the necessary data both from the primary and secondary sources. The research design is of a cross-sectional type in nature. Our binary logit regression showed that, the stock of social capital has favorable impact on the households’ economic wellbeing in Jimma zone. Besides, the economic impact of households’ special stock of social capital was found to be more relevant compared to their general stock of social capital. Hence, general social capital need to be taken as an opportunity to create special social capitals, as the later is meant to favor the households’ wellbeing.
Journal of Analytical Techniques and Research, Volume 1; https://doi.org/10.26502/jatri.008
Journal of Analytical Techniques and Research, Volume 2, pp 110-112; https://doi.org/10.26502/jatri.015
Heparin is used in plasma fractionation processes to prevent activation of coagulation factors. Consequently, intermediates and final products have to be measured for their heparin content. Established chromogenic heparin assays rely on measurement of the accelerated inhibitory action of antithrombin against thrombin or activated factor X. These assays, however, show limitations, especially at the low sample dilutions required to provide adequate sensitivity. These limitations, potentially biasing results, originate from the specific sample matrix including proteases or protease inhibitors or from the test sample’s color. To overcome these shortcomings, a commercially available competitive enzyme-linked immunosorbent assay (ELISA) was established, described so far to measure heparin in plasma only. Briefly, heparin contained in the sample competed with the binding of a peroxidase-labelled heparin binding protein to the wells of a heparin-coated plate. The six-point calibration curve ranging from 0.03 to 7.14 IU heparin/mL showed acceptable accuracy and reproducibility. Test samples were diluted at least 1/6 in normal human citrated plasma. Spike-recovery was carried out by adding heparin to obtain a concentration of 0.26 IU/mL in the test dilution of the respective sample. Acceptable recovery was found in all sample types investigated (final immunoglobulin G product and process intermediates, albumin and α1-proteinase inhibitor), while intra-and inter-run precision data showed relative standard deviations lower than 10%. The ELISA’s limit of quantification was 0.18 IU/mL, thus demonstrating required sensitivity. In summary, the competitive heparin ELISA allowed accurate, precise and sensitive heparin measurement in specific plasma protein matrices, which interfere with chromogenic heparin assays.