Research Progress of Raman Spectroscopy and Raman Imaging in Pharmaceutical Analysis.

The analytical investigation of the pharmaceutical process monitors the critical process parameters of the drug, beginning from its development until marketing and post-marketing, and appropriate corrective action can be taken to change the pharmaceutical design at any stage of the process. Advanced analytical methods, such as Raman spectroscopy, are particularly suitable for use in the field of drug analysis, especially for qualitative and quantitative work, due to the advantages of simple sample preparation, fast, non-destructive analysis speed and effective avoidance of moisture interference. Advanced Raman imaging techniques have gradually become a powerful alternative method for monitoring changes in polymorph distribution and active pharmaceutical ingredient distribution in drug processing and pharmacokinetics. Surface-enhanced Raman spectroscopy (SERS) has also solved the inherent insensitivity and fluorescence problems of Raman, which has made good progress in the field of illegal drug analysis. This review summarizes the application of Raman spectroscopy and imaging technology, which are used in the qualitative and quantitative analysis of solid tablets, quality control of the production process, drug crystal analysis, illegal drug analysis, and monitoring of drug dissolution and release in the field of drug analysis in recent years.

Additively manufactured electrodes for the electrochemical detection of hydroxychloroquine.

Although studies have demonstrated the inactivity of hydroxychloroquine (HCQ) towards SARS-CoV-2, this compound was one of the most prescribed by medical organizations for the treatment of hospitalized patients during the coronavirus pandemic. As a result of it, HCQ has been considered as a potential emerging contaminant in aquatic environments. In this context, we propose a complete electrochemical device comprising cell and working electrode fabricated by the additive manufacture (3D-printing) technology for HCQ monitoring. For this, a 3D-printed working electrode made of a conductive PLA containing carbon black assembled in a 3D-printed cell was associated with square wave voltammetry (SWV) for the fast and sensitive determination of HCQ. After a simple surface activation procedure, the proposed 3D-printed sensor showed a linear response towards HCQ detection (0.4-7.5 µmol L-1) with a limit of detection of 0.04 µmol L-1 and precision of 2.4% (n = 10). The applicability of this device was shown to the analysis of pharmaceutical and water samples. Recovery values between 99 and 112% were achieved for tap water samples and, in addition, the obtained concentration values for pharmaceutical tablets agreed with the values obtained by spectrophotometry (UV region) at a 95% confidence level. The proposed device combined with portable instrumentation is promising for on-site HCQ detection.