Pharmaceutical Analysis

I am delighted to present this special issue with a theme of pharmaceutical analysis to Analytical Methods readers. Most of us would quite rightly translate pharmaceutical analysis as the application of analytical measurements in industrial drug discovery and development laboratories. In such settings, of course, the broad purpose of measurement science is to provide evidence of understanding around the efficacy and safety of pharmaceutical products to regulatory bodies in the quest for approvals of new medicines. In truth though, pharmaceutical analysis (or should we say analysis of pharmaceuticals) is a broader umbrella which is an important area of focus for measurement scientists working in, for example, clinical chemistry, toxicology and environmental chemistry laboratories. Some of the applications presented in this issue are indeed appropriate for such areas; examples include those by Kataoka and co-workers who developed methodology based around online SPME coupled with HPLC-MS/MS and the novel application of chemiluminescence methodology for determination of isoproterenol in human serum (as well as pharmaceutical samples) by Rezaei and colleagues.

Various examples of work presented in this issue though are focused on the more traditional industrial drug discovery and development settings and one such contribution is that by Clegg and co-authors. This paper is an excellent example of how NMR spectroscopy can be employed in reaction monitoring of a whole synthetic route from starting materials through reaction products and intermediates to the final drug substance during the drug development lifecycle. Application of the NMR technology in parallel to the more widely used mid-infra-red spectroscopy provided complementary data and thus enhanced confidence in understanding of each reaction in the synthesis. If such an approach were adopted by more laboratories in the industry, it would likely increase the number of PAT methods employed routinely at commercial manufacturing scale.

Another original paper in this area is that by Shinzawa and co-workers. These authors present on their detailed study of how tablet compression affects sustained release and water absorption properties of cellulose excipients. Their study involved application of near infrared spectroscopy, X-ray diffraction and X-ray computed tomography together with water absorption and dissolution measurements to elucidate the impact of compression on these properties. This is another example of how appropriate application of measurement technologies in combination can lead to enhanced product understanding and product design ability. Yet another body of work demonstrating a new strategy to enhance understanding of a system related to industrial pharmaceutical analysis is that presented by Stefan-van Staden and Bokretsion who detail their studies to develop enantioselective potentiometric membrane electrodes and who also elucidate the intermolecular interactions between their chiral selectors using ab initio molecular orbital theory. Such an approach may be promising with respect to being able to elucidate the enantioselectivity of such membrane systems, or indeed other enantioselective systems.

It is also noteworthy that a large majority of the papers in this issue have a common theme whereby novel measurement methods are presented with exhibiting enhanced speed, sensitivity and robustness with reduced sample work-up. These are all features which are increasingly important in the modern pharmaceutical industry where cost-reduction, increased quality and speed are required alongside environmental and societal demands to reduce environmental impact and strive for more sustainable manufacturing. Examples of such papers are those by Havilkova et al. who describe a novel and simple RP-HPLC method employing UV and fluorimetric detection for simultaneous determination of anthelmintic drugs, or that by Passoni and colleagues who describe a new rapid RP-HPLC method for determination of lyophilized teicoplanin.

The papers in this issue while only representing a small snapshot of the types of measurement science now being applied to better understand pharmaceuticals demonstrate how important pharmaceutical analysis is as an underpinning platform to drug discovery and development. Further, there is evidence here that the increasing cross pollination of mathematical, physical and chemical sciences is facilitating delivery of elegant technologies and analytical strategies which can only serve to help the industry in the quest to deliver better medicines, faster.

Melissa Hanna-Brown

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