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The key differences between a classical balance and currently available automated systems from the good weighing practice (GWP) perspective and within the scope of ISO9001:2015 quality standard are discussed. The systems under review are: (i) manual analytical balances; (ii) semi‑automatic systems; (iii) fully automatic systems; and (iv) integrated systems that use on-line coupling of the analytical balance with the instrument used for analytical measurements. The parameters defined in GWP guidelines, such as accuracy, uncertainty, minimum weight, and risks (including out‑of‑specification results), will be evaluated for all of these systems.

It is often possible to achieve better sensitivity and lower limits of detection and quantitation using standard gas chromatography (GC) equipment-here I’m referring to a standard split/splitless injection port and a Flame Ionization Detector (FID). Paying attention to some of the fundamental variables as well as some of the more esoteric considerations can lead to much improved method performance.

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The use of superficially porous particles (SPPs) for modern high performance liquid chromatography (HPLC) is now very common. Initially, SPPs rose as an alternative to sub-2-µm fully porous particles (FPPs). In recent years, many column manufacturers have developed 2-µm and smaller SPP-based products. This article investigates the practical utility of these smaller SPP designs.

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While capillary gas chromatography has been undergoing a renaissance, with new columns, detectors, data systems, and multidimensional separations, the classical inlets have remained the same: We are still injecting liquid samples with syringes into split and splitless inlets, as we have for nearly 50 years. Split and splitless injections present several well-known and some not-so-well known challenges, mostly arising from heating of the inlet, that make sample injection and inlets a major hurdle for gas chromatographers. These challenges and some ideas for mitigating them are discussed and a case is made for renewed exploration of the cool inlets and injection techniques: cool on-column and programmed temperature vaporization.

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This is the first of three articles looking at the impact of the new United States Pharmacopeia (USP) chapter on Analytical Instrument Qualification (AIQ) on data integrity in a regulated chromatography labora-tory. In part 1, user specifications for chromatography systems and the relationship between users and sup-pliers will be discussed.