The Best of Bioanalysis 2010

Keywords::

• advisory panel
• bioanalysis
• editorial
• journal

The year 2010 was again a marvelous year for the journal. Bioanalysis underwent tremendous growth, expanding from nine issues last year to 12 in 2010. The number of research articles more than doubled in 2010, increasing from 21 to 55. The same trend is also true for editorials (15 vs 32 for 2009 and 2010, respectively). We believe this reflects the niche that Bioanalysis fills, by providing a forum for high-quality research and discussion for this community. Consequently, selecting a ‘best’ article of the year was even more challenging than last year [1]. Choosing the ‘best’ of an eclectic group of papers such as those published in Bioanalysis is largely going to be one of personal preference, as such, like 2009, we will present the criteria upon which our decision was made. We also sought the opinions of our esteemed editorial board members to help with the selection.

Brian

Overall, I found that all of the articles published in 2010 were interesting and informative. My preference is for application of our science to ‘real world issues’ and for efforts that further our knowledge. Table 1[2–15] provides a shortlist of what I thought were examples of the best research papers and the most topical reviews published in 2010.

From Table 1, my five favorite articles from 2010 are:

• Jinchuan Sun et al., who described the use of LC–MS as a metabolomics tool. These authors reported on a study they conducted to find potential biomarkers of renal and hepatic injury after treating rats with valproic acid, a drug known to cause renal injury [3];

• Ulrike Andree et al., who described their work to develop surface plasmon resonance methodology to assess tetracycline traces in food [4];

• Nicoletta Mitrea et al., who used LC–MS to assess structural changes to peptides [10];

• Daniel Blessborn et al., who described the assay they developed using dried blood spots (DBS) to screen for seven analytes [14];

• Anthony Butterfield et al., who proposed a strategy for evaluating several immunogenicity testing paradigms [15].

Howard

There are many excellent papers illustrating new and emerging concepts for which there is not an immediate role in the current drug-development strategy, although in 5–10 years they may become pivotal components of that strategy. For the moment I shall concentrate on those hot topics that look likely to drive, or have the potential to drive, the drug-development process forward over the next 2–5 years by reducing development timelines, providing information-rich results or which, in the vernacular, provide more ‘bang for the buck’.

Currently the frontrunners are the role of DBS, metabolites in safety testing (MIST) philosophy and enabling technologies such as accelerator MS (AMS) and high-resolution MS approaches, which through high-sensitivity and highly specific detectors are providing information-rich outputs.

From the philosophical perspective, global harmonization and the possibility of minimizing the need to reinvent the wheel for multifarious regulatory authorities are pivotal considerations in streamlining the drug-development process. While in the wings the roles of nanotechnology and microfluidics wait to be fully exploited.

There was a plethora of papers on globalization and bringing pragmatism to regulated bioanalysis including “Request for Global Harmonization of the Guidance for Bioanalytical Method validation and sample analysis” [16] and “International Harmonization of Bioanalytical Guidance” [17], but not limited to these, I counted over ten such related articles.

The relevance of DBS has been highlighted in several papers published within the two special editions [18,19] and a few others outside these, while Emmons and Rowlands eloquently reviewed the relevance and importance of DBS to pharmacokinetics [20].

The application of AMS to microdosing was also the subject of a special edition [21], as a result the role of AMS in microtracer studies would seem to have broader application as highlighted in the special issue in papers from Vitalea and Xceleron.

While those technologies due to make a splash in the next few years were sparsely represented, such as HRMS, miniaturization and microfluidics, they were mentioned ‘in passing’ in some research papers [21].

A major underlying theme in many of my choices is expediting the process of identifying metabolites at the appropriate time in the development process using the appropriate technologies. As such the White Paper “Best practices in a tiered approach to metabolite quantification: views and recommendations of the European Bioanalysis Forum” [22] best illustrates the issues and provides a road map based upon the experiences and views of a wide range of researchers. While this represents the philosophical approaches, the practical aspects of MIST are addressed in a wide range of papers, the first of these being “Novel MS solutions inspired by MIST”[23]. This paper also highlights the current role of ‘metabolism’ studies in the drug development program. Future perspectives predict that HRMS will be combined with automated metabolite id software tools such as mass defect filters. In the next paper, “A radio-calibration method with pseudo internal standard to estimate circulating metabolite concentrations” [24], 100 uCi is at the extreme of ¹⁴C human dosing when compared with microdosing, yet it presents some interesting ways of achieving the same objective, albeit at a later time in the drug development program. Perhaps there would be merit in a comparison of cost, data utility and quality to be made between these approaches as cost becomes an increasingly significant consideration in the utility of some of these approaches.

The major alternative to high-dose radiolabeled studies are microdosing studies, starting with “Microdosing in early lead discovery” [25], a nice overview, which discusses the issue that the real importance of Phase 0 trials in drug development is not really known until agents under study are successfully approved. Compare and contrast this with Dennis Smith’s view in the 2011 edition where he implies it is time to exploit this technology and stop equivocating – my summary of his commentary [26]. In “Early human absorption, distribution, metabolism and excretion (ADME) using microdoses and microtracers: bioanalytical considerations” [6], the authors argue emphatically and convincingly for the early use of microdosing in human studies. The most forceful case for the use of this technology is not just in early/discovery phase studies, but in its ability to replace or augment current processes that “we have always done in this way”. This is reinforced by the next three papers authored; for example by Lappin and Seymour in their review “Addressing metabolite safety during first in man studies using ¹⁴C-labeled drug and accelerator MS” [27]. Is it early Phase 0 or could it be used to fulfil regulatory requirements as well as providing early answers on metabolic fate?

It would be a surprise, with two special editions on DBS, if we did not have a contender from the main proponents of this approach. One such article is by Philip Denniff and Neil Spooner entitled “Effect of storage conditions on the weight and appearance of dried blood spot samples on various cellulosed-based substrates” [28]. This paper sounds a warning on the impact of the environment on the “integrity of the substrate and DBS samples, not surprisingly, it emphasizes that like new methods, new technologies are not fully validated until their robustness has been tested under a variety of conditions. A second paper by the same authors sends another warning about factors influencing the use of DBS [29]; this is particularly important in diseased patients where hematocrit can vary widely throughout the course of the disease. The review by Asgeir Johannessen on “Dried blood spots in HIV monitoring: applications in resource-limited settings [30]”, provides a positive approach where DBS has many advantages in extreme environments (and conditions) and possibly the only way of collecting blood samples in such an environment. While an unlikely entry, Dennis Smith’s commentary, “Does validation stagnate innovation” [31], is a contender for the most thought-provoking comment in relation to DBS in particular, but maybe it also has broader implications! Applying the DBS approach to metabolite identification, the article “Exploring the feasibility of using the DBS technique for metabolite radio profiling” [32] is yet one more technology to help expedite the MIST process by Lijuan Wang, Zhaopie Zeng and Gary Emmons. On the other hand, Celia J D‘Arienzo’s paper, “DBS sampling can be used to stabilize prodrugs in drug discovery rodent studies without the addition of esterase inhibitors” addresses the major problem of instability of drugs in rat plasma in early research, and offers a possible way forward that is easier to execute than current technologies [33]. Peter Prince extends the role of DBS to therapeutic antibodies and presents an early step in making DBS the matrix of choice for all therapeutic classes [11].

The Bioanalytical Challenge article on “Challenges in urine bioanalytical assays: overcoming nonspecific binding” by Allena Ji [34] links in well with a research article by Kadar on “Evaluation of the relationship between a pharmaceutical compound’s distribution coefficient, log D and adsorption to polypropylene in urine and CSF” [35]. Adsorption (and to some extent absorption) have always been the elephant in the room. Is there adsorption or is there instability? Usually adsorption is found guilty by a process of elimination and rectified by the use of empirical observations. This is an excellent article looking at the possible factors (almost first principles) associated with adsorption and the use of ‘corrective measures’. This is a paper with potentially extremely wide implications and, when read in conjunction with the paper by Ji et al., provides a comprehensive overview of the issue.

“Comparison of assay formats for drug-tolerant immunogenicity testing” is a useful contribution in this important area of drug development where formats and instrumentation proliferate, the authors have carried out the experiments that everybody would like to conduct but never got round to. The results are especially useful to a broad range of researchers [15].

“Unwanted immunogenicity: lessons learnt and future challenges” describes perhaps the greatest safety risk for biotherapeutics[36]. Methods to assess these issues are, like the regulatory guidances and commentaries by the regulators, developing apace. The authors question and discuss the long held maxim, also held by the regulators (European Medicines Agency) that the use of bioassays for assessing neutralizing antibodies is the gold standard in developing neutralizing antibody assays [36].

In “Micro open-sandwich ELISA to rapidly evaluate thyroid hormone concentration from serum samples”, it is perhaps not the specific application of this technique but the broader application to other diagnostic markers (biomarkers) using microfluidics and ‘immune‘-based detection/quantitation systems in which its value lies. Only time will confirm the robustness of this approach [13].

“Therapeutic monoclonal antibody concentration monitoring: free or total” [37] is a great review of assay formats and discussion as to how this can be achieved can be best summarized by a quote from the executive summary: “An analytical method that does not perturb the binding equilibrium would be ideal to directly measure the free and bound fractions of therapeutic antibodies in biological samples.”

Comparing reviews with research articles is fraught with difficulty. By their nature, reviews encompass quantum leaps in research and can provide the reader with a time saving evaluation of the quality of the papers reviewed while research articles by their nature provide smaller advances in their science. So to my final three:

• The review article by Dueker et al. “Early human ADME using microdoses and microtracers: bioanalytical considerations”. Although this is a review it draws heavily on the main contributors from this field, including Vitalea, from where the authors originate, and as such draws heavily on their original work [6].

• The next article meriting high praise is the comprehensive overview of MIST by the European Bioanalysis Forum, which provides an excellent discussion and well thought out way forward on this hot topic [22].

• Third, the research article by Kadar et al., “Evaluation of the relationship between a pharmaceutical compound’s distribution coefficient, log D and adsorption loss to polypropylene in urine and CSF”– which nicely ties theory based on physicochemical parameters with real life observations; an elegant and practical paper [35].

I must confess that the order in which I have listed them is the order in which I rank them so the review paper by Dueker et al. is my overall personal winner.

Editorial advisory panel

The Bioanalysis editorial advisory panel plays a key role in ensuring that the journal publishes the best, most current work. We surveyed them to find out what papers they felt were the most important or made the biggest impact in 2010. Table 2[3,9,16,20,22,31,37–45] includes a summary of their choices and reasons for their selection.

And the winner is…

As can be seen from the diverse selections of the editorial board and us, the senior editors, it is an almost impossible task to pick a single overall winner this year. This certainly exemplifies the high-quality work published in our journal and its hugely diverse appeal and impact. However, in an effort to avoid being too politically correct and classing the journal readers as the overall winner, we thought it appropriate to select a few articles that had a big impact in the following areas.

MIST

It was a close call between the European Bioanalysis Forum’s White Paper describing a tiered approach to metabolite quantification and the favorite in this category, the review article by Dueker et al.[6].

DBS

DBS are currently of great interest for the bioanalytical research community, so the top selection had to include an article in this area. The contenders include the humorous Editorial by Smith [31], and the Commentary by Emmons and Rowland, which highlights the differences between blood and plasma concentrations. However, we have chosen the paper by Blessborn et al.[14], who developed a method to screen for seven antimalaria drugs using DBS, demonstrating the technique’s applicability in resource-limited settings.

Macromolecules

In the rapidly growing biotherapeutics arena, we chose the article by Butterfield et al., which describes a series of experiments to determine the most appropriate assay for drug-tolerant immunogenicity testing, as the results have a broad impact on a wide range of researchers [15].

Congratulations to the authors of our three winning papers; these are all now available as free downloads in the BioanalysisZone[101] – we hope that you enjoy reading them.

Finally, we would like to conclude by thanking all of our authors, peer reviewers and readers for their contributions to the journal. Keep up the good work, and we look forward to more difficult decisions in highlighting the best of 2011.

Table 1. Research and review articles published in 2010.

Authors	Title	Published	Topic	Type of article	Ref.
Robert MacNeill, Timothy Sangster, Marc Moussallie, Vincent Trinh, Ryan Stromeyer and Erinne Daley	Stable-labeled analogues and reliable quantification on nonprotein biomarkers by LC–MS/MS	January	Steps taken to select a stable-labeled analogue as IS	Research	[2]
Jinchuan Sun, Laura K Schhnackenberg, Deborah K Hansen and Richard D Beger	Study of valproic acid-induced endogenous and exogenous metabolite alterations using LC–MS-based metabolomics	February	LC–MS used to search for markers of hepatic and renal injury	Research	[3]
Ulrike Andree,Erika Mueller-Seitz, Igor Usai, Stefan Loeber, Peter Gmeiner, Cornelius Wimmer, Wolfgang Hillen and Michael Petz	Tetracycline sensing using novel doxycycline derivatives immobilized on different surface plasmon resonance biosensor surfaces	February	Development of SPR assay for tetracycline analysis in food	Research	[4]
David P Thomas and Joe P Foley	Detection of prohibited substances in equestrian sport through direct injection of equine serum using micellar LC	February	Sample prep for LC–MS using surfactants in whole blood sample	Research	[5]
Stephen R Dueker, Peter N Lohstroh, Jason A Giacomo, Le T Vuong, Bradley D Keck and John S Vogel	Early human ADME using microdoses and microtracers: bioanalytical considerations	March	Issues in the use of microdosing and AMS	Research	[6]
Ami C Bautista, Danika Wullner, Mike Moxness, Steven J Swanson, Navendra Chirmule and Vibha Jawa	Impact of matrix-associated soluble factors on the specificity of the immunogenicity assessment	April	Assessed matrix effects on measurement of immunogenicity Abs	Research	[7]
Steve Goodison, Yijun Sun and Virginia Urquidi	Derivation of cancer diagnostic and prognostic signatures from gene expression data	May	Strategies for looking at gene expressions that may be biomarkers for cancer	Research	[8]
Daniel E Mulvana	Critical topics in ensuring data quality in bioanalytical LC–MS method development	June	Tricky areas of LC–MS; IS, matrix effects, stability	Review	[9]
Nicoleta Mitrea, Andre LeBlanc, Maude St-Onge and Lekha Selno	Assessing covalent binding of reactive drug metabolites by complete protein digestion and LC–MS analysis	July	Determination of protein peptide modification using LC–MS	Research	[10]
Peter J Prince, Katerine C Matsuda, MW Retter and G Scott	Assessment of DBS technology for the detection of therapeutic antibodies	August	Study assessing the application of DBS sampling for antibody drugs	Review	[11]
Dianna Y Wu, Lisa Patti-Diaz and Carla G Hill	Development and validation of flow cytometry methods for pharmacodynamic clinical biomarkers	September	Validation of flow cytometry	Research	[12]
Kamrun Nahar Islam, Masaki Ihara, Junhua Dong, Noriyuki Kasagi, Toshihiro Mori and Hiroshi Ueda	Micro open-sandwich ELISA to rapidly evaluate thyroid hormone concentration from serum samples	October	Open-sandwich ELISA method employing microfluidics to measure T4 with potential diagnostic applications for patients	Research	[13]
Daniel Blessborn, Susanne Romsing, Yngve Bergqvist and Niklas Lindegardh	Assay for screening for six antimalarial drugs and one metabolite using dried blood spot sampling, sequential extraction and ion-trap detection	November	Developed for patient monitoring	Review	[14]
Anthony M Butterfield, Jana S Chain, Bradley Ackerman and Robert J Konrad	Comparison of assay formats for drug-tolerant immunogenicity testing	December	Prospectively examined three assays to determine best for immunogenicity testing	Research	[15]

ADME: Adsorption, distribution, metabolism and excretion; AMS: Accelerator MS; DBS: Dried blood spots; IS: Internal standard.

Table 2. Editorial board recommendations for best article.

Editorial board member	Favorite paper	Reason	Ref.
Mark Arnold	Pharmacokinetic considerations as to when to use dried blood spot sampling	In the frenzy to get on the DBS bandwagon, bioanalysts have lost sight of many of the fundamental issues of pharmacokinetics and the implications of differences between blood and plasma concentrations; especially in light of recent findings related to hematocrit on blood spot distribution	[20]
Daniel Bracewell	Absolute quantification of a therapeutic domain antibody	An exciting use of the latest analytical technology to quantify new biotherapeutic molecules in serum without recourse to specific capture of detection reagents	[38]
David Barrett	Chromatography with higher pressure, smaller particles and higher temperature: a bioanalytical perspective	This was a well-organized and effective review of UPLC and HTLC with a clear bioanalytical relevance. It gave a useful summary of methods as well as highlighting practical advantages and disadvantages of these increasingly used methods	[39]
Patrick Camilleri	Use of DBS sample collection to determine circulating drug concentrations in clinical trials: practicalities and considerations	The authors have very clearly given a detailed description of the DBS technique in a structured manner, and have shown its successful application to ‘real’ bioanalytical and pharmacokinetic measurements	[40]
Neil Spooner	Does validation stagnate innovation?	This was a brave and humorous article that challenged the current conservative attitude to anything new in bioanalysis because of fear of what others might think	[31]
Fabio Garofolo	Elimination of LC–MS/MS matrix effect due to phospholipids using specific solid-phase extraction elution conditions	It has been a milestone in understanding the retention of phospholipids on SPE material. It seems that it has also been used by vendors such as Waters to patent their new cartridges	[41]
Fengguo Xu	Elimination of LC–MS/MS matrix effect due to phospholipids using specific solid-phase extraction elution conditions	Matrix effect is a nightmare born along with LC–ESI-MS and usually leads to worse accuracy and precision, especially in biomedical analysis. How to get rid of this effect is a big challenge for all scientists. This paper showed us a good example of how to monitor and eliminate the matrix effect in LC–MS bioanalysis	[41]
Michael G Weller	Bioanalytical solutions to acetonitrile shortages	This paper discusses a very practical topic, which should be of interest for a broad group of readers	[42]
Hiroshi Kamimori	Bioanalytical solutions to acetonitrile shortages	This article involves an usefully variable imformation for sample preparation, especially, protein preciritations. When we develop the analytical method by LC–MS/MS, we can refer to this paper for information. Also, it can accelerate the speed of setting up sample preparation	[42]
Ramesh Mullangi	Sensitivity and proportionality assessment of metabolites from microdose to high dose in rats using LC–MS/MS	This paper is going to show a new avenue in microdosing utility in preclinical species and will be useful to quantify metabolites along with the parent compound, which will be very helpful to assess and establish the in vitro to in vivo translation of metabolite(s) formation pattern. By assessing the metabolite(s) formation by microdosing helps us to speculate the metabolite(s) in humans. In addition, with increments in dose, the formation of metabolite(s) can be known and we can also assess the parent and metabolite(s) pharmacokinetic parameters proportionality	[43]
Daniel Tang	Request for Global Harmonization of the Guidance for Bioanalytical Method Validation and Sample Analysis	This publication is very short but is having a huge impact because the worldwide bioanalytical community, together with regulatory agencies, will spend a lot of effort in the next year or two on this initiative	[16]
Yunsheng Hsieh	Study of valprolic acid-induced endogenous and exgenous metabolite alterations using LC–MS-based metabolomics	This paper demonstrated the discovery of important tox-related biomarkers via metabolomic studies using an LC–MS -based approach, which is very helpful during the lead optimization stage in mordern pharmaceutical industry	[3]
Berit Packert Jensen	Critical topics in ensuring data quality in bioanalytical LC–MS method development	I liked the review for its thoroughness and for giving lots of references to papers on these issues and how to monitor/minimize them. I found it very relevant for my work and it increased my awareness of some potential quality issues we might have in our laboratory	[9]
Marcel Musteata	Toward point-of-care microchip profiling of proteins	This is a well written review of the recent efforts in developing rugged microfluidic devices for clinical applications. The reader of the article gets a good grasp on the status of this technology and its implications in patient care	[44]
Perry Wang	2010 White Paper on Recent Issues in regulated Bioanalysis and global harmonization of bioanalytical guidance	It discussed several ‘hot’ topics concerning bioanalytical issues and regulatory challenges, which interest me most	[45]
Aiming Yu	Best practices in a tiered approach to metabolite quantification: views and recommendations of the European Bioanalysis Forum	This paper introduces the recommendations on metabolite analysis from the European Bioanalysis Forum, based on the US FDA and ICH guidance. The authors discussed the three tiers of metabolite analysis approaches: screening, qualified and validated assays, and their application to the drug discovery and development process, regarding how and when to use different approaches for metabolite analysis, although technical challenges remain to be solved case-by-case	[22]
Roland Staack	Therapeutic monoclonal antibody concentration monitoring: free or total?	The paper nicely describes a ‘hot topic’ in the field. Such papers, as well as the perspectives, are making the difference between Bioanalysis and other journals. They will attract the attention to the journal because such articles will be discussed within the community	[37]

DBS: Dried blood spots; HTLC: High-temperature LC.

Disclaimer

The views expressed are those of the authors and do not reflect official policy of the US FDA. No official endorsement by the FDA is intended or should be inferred.

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.