Positron Annihilation Lifetime Spectroscopy as a Special Technique for the Solid-State Characterization of Pharmaceutical Excipients, Drug Delivery Systems, and Medical Devices—A Systematic Review

Abstract

The aims of this systematic review are to explore the possibilities of using the positron annihilation lifetime spectroscopy (PALS) method in the pharmaceutical industry and to examine the application of PALS as a supportive, predictive method during the research process. In addition, the review aims to provide a comprehensive picture of additional medical and pharmaceutical uses, as the application of the PALS test method is limited and not widely known in this sector. We collected the scientific literature of the last 20 years (2002–2022) from several databases (PubMed, Embase, SciFinder-n, and Google Scholar) and evaluated the data gathered in relation to the combination of three directives, namely, the utilization of the PALS method, the testing of solid systems, and their application in the medical and pharmaceutical fields. The application of the PALS method is discussed based on three large groups: substances, drug delivery systems, and medical devices, starting with simpler systems and moving to more complex ones. The results are discussed based on the functionality of the PALS method, via microstructural analysis, the tracking of ageing and microstructural changes during stability testing, the examination of the effects of excipients and external factors, and defect characterization, with a strong emphasis on the benefits of this technique. The review highlights the wide range of possible applications of the PALS method as a non-invasive analytical tool for examining microstructures and monitoring changes; it can be effectively applied in many fields, alone or with complementary testing methods.

Fast and convenient delivery of fluidextracts liquorice through electrospun core-shell nanohybrids

“…With the gradual expansion of electrospinning in pharmaceutics, its ability to convert dosage forms is drawing increasing attention ( Németh et al, 2022 ; Shokoya et al, 2023 ). The well-known unique properties of electrospun nanofibers (including small diameter, high porosity, large surface area, and simple fabrication) are showing merit for pharmaceutical applications, such as the amorphous state of drugs, their simple storage and good stability, fast dissolution, simple encapsulation of all kinds of active ingredients (oil, herbal medicines, proteins and peptides, and small chemical molecules), strong capability of synthesizing structural hybrids from a combination of filament-forming polymeric excipients, as well as excipients without electrospinnability (such as lipids, surfactants, and even inorganic materials), and the simple conversions of electrospun nanofibers as intermediate dosage forms to final medical products ( Weaver et al, 2022 ).…”

Annealing effects on the structural, positron annihilation parameters, and electrical properties of Fe2O3- PbO2-TeO2 glasses

“…Positron annihilation spectroscopy (PAL) has been used to study some charge transfer molecular complexes [5] and vacancies in some molecular materials [6,7]. Saddeek et al [8] studied the essential examination of different shapes of glasses using ultrasonic and PAL tools.…”