Jpc-journal of Planar Chromatography-modern Tlc最新文献

This article offers a personal retrospective and forward-looking analysis of high-performance thin-layer chromatography (HPTLC), tracing its evolution from inception to its current status as an analytical methodology. It covers pivotal milestones, technological advancements, and standardization protocols, shedding light on important contributions of various stakeholders. The article also explores potential future trajectories and emerging trends in HPTLC. Through this retrospective and forward-thinking analysis, the article contributes to a comprehensive understanding of HPTLC’s past, present, and future in the realm of chromatography in routine quality control.

E 472 emulsifiers are organic acid esters of mono- and diacylglycerides. These emulsifiers are categorized into six subgroups (E 472a-f) based on the specific acid component, e.g., acetic acid, lactic acid, citric acid, tartaric acid, or mixtures of tartaric and acetic acid. The present study investigated the effect of relative humidity (RH) on the thin-layer chromatographic separation of four E 472 emulsifier subgroups, addressing practical concerns due to RH variations between seasons and within laboratories. Three RH-setting techniques affecting plate activity and chamber climate were assessed using saturated salt and aqueous sulfuric acid solutions. Aqueous sulfuric acid solutions for RH adjustment resulted in decreased hR_F values, while no trends in hR_F value changes were observed for saturated salt solutions. Unlike RH itself, the RH setting technique led to substantial changes in the chromatographic fingerprint. Thus, the choice of the RH setting method should be tailored to the specific analyte and analysis goal. Despite variations in chromatographic fingerprints between the three RH setting techniques, the fingerprint remained consistent within the same technique across the tested RH range.

Quality assessment is the most important step in the production of effective and safe food supplements. The aim of this study is to develop a green, simple, and high-throughput procedure for the quality assessment of Origanum vulgare L. commercial products using high-performance thin-layer chromatography (HPTLC)/bioautography with a multicriteria decision method, sum of ranking differences (SRD). Direct bioautography assays were developed for the identification of constituents with antibacterial activity tested against Gram-positive (Bacillus subtilis, Micrococcus lysodeikticus) and Gram-negative (Escherichia coli) strains, antioxidative (DPPH) activity, and enzyme (α-amylase) activity. Combination of the leave-one-out cross-validation methodology of SRD values and significant differences by post hoc Wilcoxon matched pairs test were used to evaluate commercial varieties. It was proved that suggested bioautography/chemometric screening methodology could be used as guidelines for the selection of any theoretical ideal product. Analysts may have benefits from this time-saving and streamlined quality profiling.

Reversed-phase chromatography is based on a polar mobile phase and an apolar stationary phase. This separation mode is regularly used in planar (thin-layer) chromatography, and the necessary plates are commercially available. We investigated the preparation of hydrophobic plates for thin-layer chromatography by chemical vapor sorption of methyltrimethoxysilane directly onto a normal-phase plate. For this, a commercial normal-phase plate is simply exposed to the vapors of the reagent in a closed vessel. The obtained plates were characterized by infrared spectroscopy and dynamic water vapor sorption, which reported an extensive conversion of free hydroxyl groups by the reagent. The obtained plates were hydrophobic with a water contact angle close to 135°. The extent of hydrophobization precluded the use of pure water as an eluent while mixtures with organic solvents were perfectly adequate. The plates’ chromatographic performance was compared with that of C18 and paraffin-coated plates. For this, a set of parabens was separated with mixtures of acetone and water. The height of a theoretical plate was similar for the hydrophobized and the C18 plates (50–90 µm) and larger for the paraffin-coated ones. In contrast to the C18 plate, the hydrophobized and the paraffin-coated plates showed some selectivity for the analyte pair n-butylparaben and iso-butylparaben, which indicates a separation mechanism with the potential for regioselectivity.

This study focusses on the development and validation of a simple, rapid and reliable high-performance thin-layer chromatography (HPTLC) method for the identification and quantification of α-mangostin in three underutilized Garcinia sp. The optimized mobile phase (chloroform‒methanol, 9:1, V/V) at 317 nm yielded sharp and well-defined peaks of α-mangostin with a constant R_F value of 0.702, ensuring consistent identification and quantification. The regression equation showed a linear function with a correlation coefficient of 0.9997. The method was validated in terms of linearity, limits of detection and quantification (LOD and LOQ), precision, accuracy, repeatability and robustness, following the International Council for Harmonisation guidelines. The low %RSD values confirmed its excellent performance. Low values of LOD (24 ng per band) and LOQ (67.75 ng per band) indicate the sensitivity of the method. Significant quantities of α-mangostin were successfully quantified in all three Garcinia sp. using the developed HPTLC method. The study indicates the three Garcinia sp. of Assam as promising sources of α-mangostin. Overall, this research contributes to scientific knowledge as well as will help in the quality control of herbal drugs and formulations containing α-mangostin.

In the pharmaceutical industry, several fixed-dose paracetamol combinations have been manufactured and marketed. Several chromatographic methods have been documented in the literature for the quality control of these fixed-dose combinations (FDCs). Yet, these chromatographic procedures were developed using teratogenic and neurotoxic organic solvents that are harmful to the environment and dangerous to human and animal life. As a result, a multipurpose chromatographic technique was developed combining principles of white analytical chemistry, quality risk assessment, and experimental design. To reduce the time and cost of analysis, this chromatographic method needs a single chromatographic condition for the quality control of multiple FDCs of paracetamol. To safeguard the environment and human life, the suggested chromatographic process employs low-toxicity possible solvents. The analytical quality risk assessment methodology by Placket‒Burman design was used to identify significant analytical method risk parameters and analytical quality attributes. Response surface analysis by mixture design was used to optimize the identified critical method risk parameters. Using unique principles of white analytical chemistry, the proposed and published chromatographic techniques were assessed for their validation efficiency, greenness profile, time efficiency, and cost efficiency for the estimation of FDCs of paracetamol with multiple drugs.

Phyllanthus niruri contains various lignan compounds, whose concentrations vary depending on several factors. This study was intended to determine the phyllanthin content of P. niruri obtained from various locations in Indonesia by using thin-layer chromatography (TLC)‒densitometry to evaluate the effect of geographical factors on their quality. The TLC system comprised silica gel 60 F₂₅₄ for the stationary phase, toluene‒ethyl acetate‒formic acid (15:10.5:1.5, V/V) for the mobile phase, and documentation under ultraviolet (UV) 254 nm light without chemical reagents. This developed method meets the specificity requirement, as marked by the identical UV spectrum between the phyllanthin sample and the standard (λ_max = 279 and 230 nm). Further, it shows good linearity for phyllanthin concentrations in the range of 2.36‒11.8 µg/band (r = 0.9924), with LOD 0.532 µg/band and LOQ 1.612 µg/band. It also has good intraday and interday precision, as indicated by RSD of 8.87–9.43 and 6.94%, respectively. Eight of the 15 analyzed samples (collected from Batu, Blitar, Kediri, Nganjuk, Jember, Mojokerto, Banyuwangi, and Surabaya) contained only a trace amount of phyllanthin. In contrast, the other seven had varying levels of phyllanthin (1.376‒4.130 mg/g dried herbs). Using the Tawangmangu sample as the reference, these seven samples can be grouped into two: significantly lower phyllanthin contents (Tulungagung) and very significantly lower phyllanthin contents (Lumajang, Bangkalan, Pasuruan, Sidoarjo, and Gresik). It can be concluded that TLC‒densitometry designed in this research is a straightforward method that, at the same time, meets the validation parameters. Therefore, it can be repeated to analyze phyllanthin in P. niruri of different phytogeographical origins.