Quantitative aspects of microchip isotachophoresis for high precision determination of main components in pharmaceuticals

Microchip isotachophoresis for green and sustainable pharmaceutical quality control: Method validation and application to complex pharmaceutical formulations

Universal microchip isotachophoresis (μITP) methods were developed for the determination of cationic and anionic macrocomponents (active pharmaceutical ingredients and counterions) in cardiovascular drugs marketed in salt form, amlodipine besylate and perindopril erbumine. The developed methods are characterized by low reagent and sample consumption, waste production and energy consumption, require only minimal sample preparation and provide fast analysis. The greenness of the proposed methods was assessed using AGREE. An internal standard addition was used to improve the quantitative parameters of μITP. The proposed methods were validated according to the ICH guideline. Linearity, precision, accuracy and specificity were evaluated for each of the studied analytes and all set validation criteria were met. Good linearity was observed in the presence of matrix and in the absence of matrix, with a correlation coefficient of at least 0.9993. The developed methods allowed precise and accurate determination of the studied analytes, the RSD of the quantitative and qualitative parameters were less than 1.5% and the recoveries ranged from 98 to 102%. The developed μITP methods were successfully applied to the determination of cationic and anionic macrocomponents in six commercially available pharmaceutical formulations.

Capillary electrophoresis in the analysis of therapeutic peptides-A review

Therapeutic peptides are a growing class of innovative drugs with high efficiency and a low risk of adverse effects. These biomolecules fall within the molecular mass range between that of small molecules and proteins. However, their inherent instability and potential for degradation underscore the importance of reliable and effective analytical methods for pharmaceutical quality control, therapeutic drug monitoring, and compliance testing. Liquid chromatography-mass spectrometry (LC-MS) has long time been the "gold standard" conventional method for peptide analysis, but capillary electrophoresis (CE) is increasingly being recognized as a complementary and, in some cases, superior, highly efficient, green, and cost-effective alternative technique. CE can separate peptides composed of different amino acids owing to differences in their net charge and size, determining their migration behavior in an electric field. This review provides a comprehensive overview of therapeutic peptides that have been used in the clinical environment for the last 25 years. It describes the properties, classification, current trends in development, and clinical use of therapeutic peptides. From the analytical point of view, it discusses the challenges associated with the analysis of therapeutic peptides in pharmaceutical and biological matrices, as well as the evaluation of CE as a whole and the comparison with LC methods. The article also highlights the use of microchip electrophoresis, nonaqueous CE, and nonconventional hydrodynamically closed CE systems and their applications. Overall, the article emphasizes the importance of developing new CE-based analytical methods to ensure the high quality, safety, and efficacy of therapeutic peptides in clinical practice.

Development of Microchip Isotachophoresis Coupled with Ion Mobility Spectrometry and Evaluation of Its Potential for the Analysis of Food, Biological and Pharmaceutical Samples

An online coupling of microchip isotachophoresis (µITP) with ion mobility spectrometry (IMS) using thermal evaporation interface is reported for the first time. This combination integrates preconcentration power of the µITP followed by unambiguous identification of trace compounds in complex samples by IMS. Short-chain carboxylic acids, chosen as model analytes, were first separated by the µITP in a discontinuous electrolyte system at pH 5–6, and subsequently evaporated at 130 °C during their transfer to the IMS analyzer. Various parameters, affecting the transfer of the separated sample components through the evaporation system, were optimized to minimize dispersion and loss of the analytes as well as to improve sensitivity. The following analytical attributes were obtained for carboxylic acids in the standard solutions: 0.1–0.3 mg L⁻¹ detection limits, 0.4–0.9 mg L⁻¹ quantitation limits, linear calibration range from the quantitation limit to 75 mg L⁻¹, 0.2–0.3% RSD of the IMS response and 98–102% accuracy. The analytical potential of the developed µITP-IMS combination was demonstrated on the analysis of various food, pharmaceutical and biological samples, in which the studied acids are naturally present. These include: apple vinegar, wine, fish sauce, saliva and ear drops. In the real samples, 0.3–0.6% RSD of the IMS response and 93–109% accuracy were obtained.

Recent Advances and Applications of Microfluidic Capillary Electrophoresis: A Comprehensive Review (2017-Mid 2019)

Microfluidic capillary electrophoresis (MCE) is the novel technique resulted from the CE mininaturization as planar separation and analysis device. This review presents and discusses various application fields of this advanced technology published in the period 2017 till mid-2019 in eight different sections including clinical, biological, single cell analysis, environmental, pharmaceuticals, food analysis, forensic and ion analysis. The need for miniaturization of CE and the consequence advantages achieved are also discussed including high-throughput, miniaturized detection, effective separation, portability and the need for micro- or even nano-volume of samples. Comprehensive tables for the MCE applications in the different studied fields are provided. Also, figure comparing the number of the published papers applying MCE in the eight discussed fields within the studied period is included. The future investigation should put into consideration the possibility of replacing conventional CE with the MCE after proper validation. Suitable validation parameters with their suitable accepted ranges should be tailored for analysis methods utilizing such unique technique (MCE).

Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2016-2018)

One of the most cited limitations of capillary and microchip electrophoresis is the poor sensitivity. This review continues to update this series of biannual reviews, first published in Electrophoresis in 2007, on developments in the field of online/in-line concentration methods in capillaries and microchips, covering the period July 2016-June 2018. It includes developments in the field of stacking, covering all methods from field-amplified sample stacking and large-volume sample stacking, through to isotachophoresis, dynamic pH junction, and sweeping. Attention is also given to online or in-line extraction methods that have been used for electrophoresis.