Synthesis of a novel betaine-type asphalt emulsifier and its investigation by online FTIR spectrophotometry

2012 ◽  
Vol 39 (2) ◽  
pp. 597-614 ◽  
Author(s):  
Chunlei Huai ◽  
Laishun Shi ◽  
Na Li
2013 ◽  
Vol 41 (4) ◽  
pp. 1935-1950 ◽  
Author(s):  
Na Li ◽  
Laishun Shi ◽  
Xuli Gong ◽  
Qiyan Xu ◽  
Xin Liu ◽  
...  

2014 ◽  
Vol 909 ◽  
pp. 72-76 ◽  
Author(s):  
Xiang Tao ◽  
Lai Shun Shi ◽  
Mei Jie Sun ◽  
Na Li

A novel cationic asphalt emulsifier of tetraethylenepentamine/formaldehyde modified lignin amine was synthesized by alkali lignin, tetraethylenepentamine and formaldehyde. The optimum reaction condition was obtained. The structure of the emulsifier was identified by FTIR. The synthesis process was monitored by online FTIR technique. Based upon the experimental data, a plausible reaction mechanism was proposed for the reaction. The target product has good surface activity and satisfactory emulsification effect. The prepared bituminous emulsion showed higher storage stability. The emulsifier belongs to slow-set asphalt emulsifier.


2014 ◽  
Vol 989-994 ◽  
pp. 189-193 ◽  
Author(s):  
Mei Jie Sun ◽  
Lai Shun Shi ◽  
Zhe Ying Jin ◽  
Na Li ◽  
Xiang Tao

A novel cationic asphalt emulsifier of N-(3-polyoxyethylene nonyl phenyl ether (10)-2-hydroxyl) propyl-N,N,N-triethyl ammonium chloride was synthesized by nonylphenol polyoxyethylene ether (NP-10), epichlorohydrin and triethylamine. The optimum reaction condition was obtained. The yield reaches 48.72% at the optimum conditions of the feedstock mole ratio of NaOH to NP-10 1.0, the mole ratio of epichlorohydrin to NP-10 1.2, the mole ratio of triethylamine to NP-10 1.2, reaction temperature 70°C, and reaction time 8 h. The structure of the emulsifier was identified by FTIR. The synthesis process was monitored by online FTIR technique and the intermediate was detected. Based upon the experimental data, a plausible reaction mechanism was proposed for the reaction. The emulsifier belongs to slow-set asphalt emulsifier.


2016 ◽  
Vol 99 (6) ◽  
pp. 1533-1536 ◽  
Author(s):  
Jéssica Sayuri Hisano Natori ◽  
Eliane Gandolpho Tótoli ◽  
Hérida Regina Nunes Salgado

Abstract Norfloxacin is a broad-spectrum antimicrobial agent, widely used in humans and animals for the treatment of urinary tract infections. It is a second-generation fluoroquinolone. Several analytical methods to analyze norfloxacin have been described in the literature. However, most of them are complex and require the use of large amounts of organic solvents. This paper describes the development and validation of a green analytical method for the determination of norfloxacin in raw material by FTIR spectrophotometry. This method does not require the use of organic solvents, minimizing waste generation in the process and its environmental impacts. The development of methods that promote the reduction, prevention, or elimination of waste generation has become highly attractive to the pharmaceutical industry because of the growing demand from civil society and government authorities for environmentally friendly products and services. The FTIR spectrophotometry method was validated according to International Conference on Harmonization guidelines, showing adequate linearity (r = 0.9936), precision, accuracy, and robustness. This validated method can be used as an environmentally friendly alternative for the quantification of norfloxacin in raw material in QC routine analysis.


2017 ◽  
Vol 100 (5) ◽  
pp. 1569-1576 ◽  
Author(s):  
Eliane Gandolpho Tótoli ◽  
Hérida Regina Nunes Salgado

Abstract Daptomycin (DPT) is an important antimicrobial agent used in clinical practice because it is very active against several types of medicinally challengingGram-positive bacteria, such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci. In addition to concerns about the quality of the analytical methods used in the QC of drugs, there is also concern about the impact of these methods on the environment. The trend toward sustainable consumption is increasingly evident and has forced the pharmaceutical industry to reduce the generation of toxic waste. Inthis context, IR spectrophotometry stands out because it does not use organic solvents and, although it is formally accepted for the identification of individual compounds, also allows the quantification of substances. Therefore, the aim of this work was to develop and validate a green analytical method for theanalysis of DPT in a lyophilized powder for injection by FTIR spectrophotometry. The method involved absorbance measurements in the spectral region of 1700–1600 cm−1. The method was properly validated and found to be linear, precise, accurate, selective, and robust for the concentrationrange between 0.2 and 0.6 mg/150 mg. The validated method was able to quantify DPT powder for injection and can be used as an environmentally friendly alternative for routine analysis in QC.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Stefany Fanelli ◽  
Alexander Zimmermann ◽  
Eliane Gandolpho Totóli ◽  
Hérida Regina Nunes Salgado

Amoxicillin is an antimicrobial agent that belongs to the penicillin compounds. Its bactericidal action causes a destruction of the cell wall of bacteria. It is widely used in clinical practice, and it belongs to the Brazilian National List of Essential Drugs (RENAME). In literature, there are some green analytical methods for the amoxicillin analysis; however, none of them is focused on its quantification in capsules. Therefore, the aim of this study was to validate an environmentally friendly analytical method for the analysis of this antimicrobial action in capsules, using spectrophotometry in the mid-infrared region. The analyses were performed in the spectral range of 1815–1736 cm−1, and the samples were analyzed as potassium bromide pellets. The method was validated according to the ICH guidelines and Brazilian legislation. Linearity, selectivity, precision, accuracy, and robustness were evaluated and showed adequate results for method validation, in a concentration range of 0.5–1.5 mg/pellet. Thus, it is concluded that the validated spectrophotometric method is able to quantify amoxicillin in capsules. In addition, it is a fast, economical, and environmentally friendly method, since it does not use organic solvents, and it can be used for quality control of routine analysis of this drug.


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