Rapid Analysis of Ingredients in Cream Using Ultrasonic Mist-Direct Analysis in Real-Time Time-of-Flight Mass Spectrometry

Comment on the "Eco-friendly and efficient extraction of polyphenols from Ligustrum robustum by deep eutectic solvent assisted ultrasound"

Qin et al. have proposed an ecological and efficient method of extraction polyphenols from the leaves of Ligustrum robustum using eutectic solvents, assisted by ultrasounds. The authors tested a number of solvents, optimized the extraction parameters and explored the extraction mechanism. According to the results of biological activity experiments of the prepared Ligustrum robustum leaves extracts, they seem promising for practical applications. The issue which is disputable is the identification of the phenolic compounds by using electrospray ionization mass spectrometry, as described in details in this comment.

Applications of mass spectrometry in cosmetic analysis: An overview

Mass spectrometry (MS) is a crucial tool in cosmetic analysis. It is widely used for ingredient screening, quality control, risk monitoring, authenticity verification, and efficacy evaluation. However, due to the diversity of cosmetic products and the rapid development of MS-based analytical methods, the relevant literature needs a more systematic collation of information on this subject to unravel the true potential of MS in cosmetic analysis. Herein, an overview of the role of MS in cosmetic analysis over the past two decades is presented. The currently used sample preparation methods, ionization techniques, and types of mass analyzers are demonstrated in detail. In addition, a brief perspective on the future development of MS for cosmetic analysis is provided.

Plasma-based ambient mass spectrometry: Recent progress and applications

Ambient mass spectrometry (AMS) has grown as a group of advanced analytical techniques that allow for the direct sampling and ionization of the analytes in different statuses from their native environment without or with minimum sample pretreatments. As a significant category of AMS, plasma-based AMS has gained a lot of attention due to its features that allow rapid, real-time, high-throughput, in vivo, and in situ analysis in various fields, including bioanalysis, pharmaceuticals, forensics, food safety, and mass spectrometry imaging. Tens of new methods have been developed since the introduction of the first plasma-based AMS technique direct analysis in real-time. This review first provides a comprehensive overview of the established plasma-based AMS techniques from their ion source configurations, mechanisms, and developments. Then, the progress of the representative applications in various scientific fields in the past 4 years (January 2017 to January 2021) has been summarized. Finally, we discuss the current challenges and propose the future directions of plasma-based AMS from our perspective.

From supramolecular to conventional polymers: polyethylene glycol

Increasing the polymerization degree of polyethylene glycol (PEG), HO-(CH₂CH₂O-)_nH, entails lowering the number of hydroxyl groups per unit volume; therefore, supramolecular polymers are gradually replaced by longer and longer conventional polymers. This paper concerns an estimation of the polymerization degree (n) where PEG changes its nature from a supramolecular polymer to a conventional polymer. It was found that that virtual transformation takes place when n reaches the value of about 9. The conclusion follows from the different thermal behaviors of the dipolar orientational effects in liquid PEG detected for n below and above 9. The result reflects a diametrically different impact of the temperature on the linkages between the monomers in supramolecular and conventional polymers.