The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are ove...The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are overlaps in the methods used by scholars. The Langmuir equation is frequently applied to model the adsorption isotherms of MIPs, providing critical insight into the capacity and affinity of the binding sites. Infrared Spectroscopy (IR) plays a crucial role in identifying the functional groups involved in the imprinting process and confirming the successful formation of specific binding sites. UV-visible spectrophotometry is employed to monitor the absorption characteristics of the polymers, offering data on the interactions between the template molecules and the polymer matrix. Transmission Electron Microscopy (TEM) provides detailed visualization of the internal structure of MIPs at the nanoscale, revealing the morphology and size of the imprinted cavities. Thermogravimetric Analysis (TGA) assesses the thermal stability and composition of the polymers, identifying decomposition patterns that are indicative of the material’s robustness under different conditions. Finally, the Laser Particle Size Analyzer is used to measure the size distribution of the polymer particles, which is critical for determining the uniformity and efficiency of the imprinting process. The six characterization methods discussed in this paper provide a comprehensive understanding of MIP, and it is hoped that in the future, more optimized design solutions will emerge and their applications in various fields will be enhanced.展开更多
[Objectives] This study was conducted to understand Radix Rehmannia quality and provide reference for selection in application. [Methods] The contents of flavonoids in five batches of commercially available samples we...[Objectives] This study was conducted to understand Radix Rehmannia quality and provide reference for selection in application. [Methods] The contents of flavonoids in five batches of commercially available samples were determined by ultraviolet spectrophotometry, and the precision and reproducibility of the determination method were analyzed. [Results] The contents of flavonoids in different batches of Radix Rehmannia samples were not completely the same, but the differences were not large overall. The experiment results have good reliability. As a medicinal plant, the climate and soil conditions of the producing areas would have an impact on the quality of Radix Rehmannia. [Conclusions] The contents of flavonoids determined in Radix Rehmannia were relatively stable, the quality was basically the same, and the overall quality was good.展开更多
Saffron, obtained from the flower stigmas of Crocus sativus L., is one of the most expensive food spices. The introduction of saffron in alpine areas could help to broaden and diversify the activities of mountain mult...Saffron, obtained from the flower stigmas of Crocus sativus L., is one of the most expensive food spices. The introduction of saffron in alpine areas could help to broaden and diversify the activities of mountain multifunctional farms, with a positive impact on economy and land management. According to ISO 3632(2010/2011), saffron can be classified into three categories of quality(I, II, III) depending on the concentration of the three main metabolites responsible for its characteristic colour, flavor and aroma: Crocin, Picrocrocin and Safranal. This study represents the first investigation of the quality of saffron produced in the Italian Alps evaluated with spectrophotometry, HPLC, solid-phase microextraction(SPME), and gas chromatographic analysis combined with mass spectrometry(GC/MS). The experiments used Crocus sativus stigmas produced in 2012-2013 in different areas of the Central Italian Alps were located at an altitude between 720 and 1200 m a.s.l.. Results obtained were compared to commercial saffron. The analyses confirmed that all samples can be classified in the first quality category according to the ISO classification. This high quality is also confirmed by HPLC analysis. Moreover, the SPME-GC/MS analysis identified some differences in the aromatic profile of saffron samples, in particular regarding safranal concentration. A preliminary assessment of the economic viability of high quality saffron production for local markets was also performed. Our study provides valid information regarding the quality and economic sustainability of saffron production in the alpine area confirming this crop as a good candidate for a new source of income for multifunctional farms in mountain areas.展开更多
The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human ...The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human urine was developed on the basis of the obtained results. The rates of catalytic and catalytic-inhibitory reaction were monitored at 700 nm （t=25 ±0.1 ℃） using UV/vis spectrophotometer. By analyzing the spectra and experimental dependences of the catalytic and catalytic-inhibitory reaction rates on the reactant concentrations, it was noticed that streptomycin attacked nitroprusside and hypochlorite causing the inhibition of the production of 2,2＇-dicarboxylindophenol. According to this effect, an analytical decrease for determination of urea by modified Berthelot reaction appeared in the presence of small amounts of streptomycin. Beer＇s law was obeyed in the interval of streptomycin sulfate concentration from 18.2 to 182 μg·mL^-1. The detection limit calculated by two methods was obtained at 11.75 μg·mL^-1 and 8.54 μg·mL^-1. The relative standard deviation of 0.55%--8.83% and the recovery of 109.10% were determined. The obtained results were validated using the referent HPLC method.展开更多
文摘The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are overlaps in the methods used by scholars. The Langmuir equation is frequently applied to model the adsorption isotherms of MIPs, providing critical insight into the capacity and affinity of the binding sites. Infrared Spectroscopy (IR) plays a crucial role in identifying the functional groups involved in the imprinting process and confirming the successful formation of specific binding sites. UV-visible spectrophotometry is employed to monitor the absorption characteristics of the polymers, offering data on the interactions between the template molecules and the polymer matrix. Transmission Electron Microscopy (TEM) provides detailed visualization of the internal structure of MIPs at the nanoscale, revealing the morphology and size of the imprinted cavities. Thermogravimetric Analysis (TGA) assesses the thermal stability and composition of the polymers, identifying decomposition patterns that are indicative of the material’s robustness under different conditions. Finally, the Laser Particle Size Analyzer is used to measure the size distribution of the polymer particles, which is critical for determining the uniformity and efficiency of the imprinting process. The six characterization methods discussed in this paper provide a comprehensive understanding of MIP, and it is hoped that in the future, more optimized design solutions will emerge and their applications in various fields will be enhanced.
文摘[Objectives] This study was conducted to understand Radix Rehmannia quality and provide reference for selection in application. [Methods] The contents of flavonoids in five batches of commercially available samples were determined by ultraviolet spectrophotometry, and the precision and reproducibility of the determination method were analyzed. [Results] The contents of flavonoids in different batches of Radix Rehmannia samples were not completely the same, but the differences were not large overall. The experiment results have good reliability. As a medicinal plant, the climate and soil conditions of the producing areas would have an impact on the quality of Radix Rehmannia. [Conclusions] The contents of flavonoids determined in Radix Rehmannia were relatively stable, the quality was basically the same, and the overall quality was good.
基金partly supported by "Accordo di Programma, affermazione in Edolo del Centro di Eccellenza Università della Montagna" MIURUniversità degli Studi di Milano, prot. no. 386 1293-05/08/2011 and by Fondazione della Comunità Bresciana- Onlus
文摘Saffron, obtained from the flower stigmas of Crocus sativus L., is one of the most expensive food spices. The introduction of saffron in alpine areas could help to broaden and diversify the activities of mountain multifunctional farms, with a positive impact on economy and land management. According to ISO 3632(2010/2011), saffron can be classified into three categories of quality(I, II, III) depending on the concentration of the three main metabolites responsible for its characteristic colour, flavor and aroma: Crocin, Picrocrocin and Safranal. This study represents the first investigation of the quality of saffron produced in the Italian Alps evaluated with spectrophotometry, HPLC, solid-phase microextraction(SPME), and gas chromatographic analysis combined with mass spectrometry(GC/MS). The experiments used Crocus sativus stigmas produced in 2012-2013 in different areas of the Central Italian Alps were located at an altitude between 720 and 1200 m a.s.l.. Results obtained were compared to commercial saffron. The analyses confirmed that all samples can be classified in the first quality category according to the ISO classification. This high quality is also confirmed by HPLC analysis. Moreover, the SPME-GC/MS analysis identified some differences in the aromatic profile of saffron samples, in particular regarding safranal concentration. A preliminary assessment of the economic viability of high quality saffron production for local markets was also performed. Our study provides valid information regarding the quality and economic sustainability of saffron production in the alpine area confirming this crop as a good candidate for a new source of income for multifunctional farms in mountain areas.
文摘The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human urine was developed on the basis of the obtained results. The rates of catalytic and catalytic-inhibitory reaction were monitored at 700 nm （t=25 ±0.1 ℃） using UV/vis spectrophotometer. By analyzing the spectra and experimental dependences of the catalytic and catalytic-inhibitory reaction rates on the reactant concentrations, it was noticed that streptomycin attacked nitroprusside and hypochlorite causing the inhibition of the production of 2,2＇-dicarboxylindophenol. According to this effect, an analytical decrease for determination of urea by modified Berthelot reaction appeared in the presence of small amounts of streptomycin. Beer＇s law was obeyed in the interval of streptomycin sulfate concentration from 18.2 to 182 μg·mL^-1. The detection limit calculated by two methods was obtained at 11.75 μg·mL^-1 and 8.54 μg·mL^-1. The relative standard deviation of 0.55%--8.83% and the recovery of 109.10% were determined. The obtained results were validated using the referent HPLC method.
