The emerging use of qPCR and dPCR in regulated bioanalysis and absence of regulatory guidance on assay validations for these platforms has resulted in discussions on lack of harmonization on assay design and appropriate acceptance criteria for these assays. Both qPCR and dPCR are extensively used to answer bioanalytical questions for novel modalities such as cell and gene therapies. Following cross-industry conversations on the lack of information and guidelines for these assays, an American Association of Pharmaceutical Scientists working group was formed to address these gaps by bringing together 37 industry experts from 24 organizations to discuss best practices to gain a better understanding in the industry and facilitate filings to health authorities. Herein, this team provides considerations on assay design, development, and validation testing for PCR assays that are used in cell and gene therapies including (1) biodistribution; (2) transgene expression; (3) viral shedding; (4) and persistence or cellular kinetics of cell therapies.
- MeSH
- Genetic Therapy * MeSH
- Polymerase Chain Reaction MeSH
- Tissue Distribution MeSH
- Drug Development * MeSH
- Publication type
- Journal Article MeSH
Liquid-liquid extraction methods are widely used for sample treatment in bioanalysis, although their implementation poses a common speed-limiting step in the analytical process when fast separation and detection methods such as UHPLC-MS are used. This study aimed to develop high-throughput salting-out assisted liquid-liquid extraction on a 96-well plate in combination with fast LC-MS analysis of ibrutinib and its active metabolite PCI-45227 (dihydrodiol ibrutinib) in human serum. A specially designed 3D printed extraction device developed in our laboratory allowed for the precise and rapid collection of the organic phase from the 96-well plate using a multichannel pipette, without the risk of aspiration of the bottom aqueous layer. The application of this device significantly accelerated sample preparation and allowed the processing of up to 96 samples in 1 h. The method was successfully validated according to EMA guidelines in the concentration range of 0.1-200 ng/mL for both analytes, providing lower limit of quantification at 100 pg/mL. The intra-day accuracy for IBT was in the range of - 1.67-5.67 %, while the inter-day accuracy was in the range of 0.20-6.90 %. The intra-day precision for IBT was in the range of 3.20-4.37 % and 3.13-4.73 % for the inter-day measurement. PCI-45227 showed intra-day accuracy in the range of - 11.2-3.71 % and the inter-day accuracy in the range of - 5.76-0.92 %. The intra-day precision for PCI was in the range of 3.49-7.64 % and 3.63-8.61 % for the measurement between days. In addition to increasing the speed of sample preparation, this method also offers low consumption of the sample and extraction solvent and can be utilized for other similar small-volume in-well plate extractions where organic solvents of lower density than water are used. The method was successfully applied to the analysis of serum samples (n = 5) of patients with chronic lymphoblastic leukaemia at the trough level (ibrutinib concentration range: 1.63-3.78 ng/mL, PCI-45227 concentration range: 1.84-14.02 ng/mL) and 2 h postdose (ibrutinib concentration range: 7.34-89.0 ng/mL, PCI-45227 concentration range: 5.64-124 ng/mL).
- MeSH
- Printing, Three-Dimensional MeSH
- Adenine analogs & derivatives MeSH
- Liquid-Liquid Extraction methods MeSH
- Percutaneous Coronary Intervention * MeSH
- Humans MeSH
- Piperidines MeSH
- Pyrazoles MeSH
- Solvents MeSH
- Tandem Mass Spectrometry * methods MeSH
- Chromatography, High Pressure Liquid methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Prezentovaná práca sa zameriava na vývoj a validáciu analytickej metódy na báze kapilárnej zónovej elektroforézy v spojení s UV detekciou pre simultánne stanovenie tramadolu a paracetamolu vo farmaceutických a biologických vzorkách. Základný elektrolyt bol tvorený 50 mM uhličitanom amónnym, ktorý predstavuje pomerne atypický elektrolytový systém. Vyvinutá metóda disponuje vhodnými validačnými parametrami ako linearita (koeficient determinácie r2 ≥ 0,995), selektivita alebo medza dôkazu na úrovni 0,25 – 0,5 μg/ml. Metóda bola charakterizovaná adekvátnymi hodnotami presnosti a správnosti, ktoré boli v súlade s kritériami validačných smerníc, či už pre matrice farmaceutického alebo biologického charakteru. Detekcia bola uskutočnená pri vlnovej dĺžke 200 nm. Daná metóda bola úspešne použitá pre potreby stanovenia tramadolu a paracetamolu v rozličných liekových formách a v biologickej matrici moču. Dosiahnuté výsledky indikujú potenciál začlenenia metódy do procesov kontroly kvality liečiv a/alebo bioanalýzy.
The aim of the present study is the development and validation of a simple method based on capillary zone electrophoresis coupled with UV detection for simultaneous determination of tramadol and paracetamol in pharmaceutical and biological samples. The background electrolyte was composed of 50 mM ammonium carbonate, which is a type of a non-conventional electrolyte system. The developed method was characterized by suitable validation parameters, such as linearity (coefficient of determination r2 ≥ 0,995), selectivity or the limit of detection at the level of 0.25 – 0.5 μg/ml. Acceptable values of accuracy and precision were obtained, which were in good agreement with the recommended validation guidelines for analysis of pharmaceutical and biological samples. Detection was performed at a wavelength of 200 nm. The developed method was successfully applied to determine tramadol and paracetamol in various dosage forms and in urine biological samples. Achieved results indicate a potential of the method to be integrated in the common quality control processes of drugs and/or in bioanalysis.
In this paper we compare electrochemical behavior of two homolog proteins, namely anterior gradient 2 (AGR2) and anterior gradient 3 (AGR3), playing an important role in cancer cell biology. The slight variation in their protein structures has an impact on protein adsorption and orientation at charged surface and also enables AGR2 and AGR3 to form heterocomplexes. We confirm interaction between AGR2 and AGR3 (i) in vitro by immunochemical and constant current chronopotentiometric stripping (CPS) analysis and (ii) in vivo by bioluminescence resonance energy transfer (BRET) assay. Mutation of AGR2 in dimerization domain (E60A) prevents development of wild type AGR2 dimers and also negatively affects interaction with wild type AGR3 as shown by CPS analysis. Beside new information about AGR2 and AGR3 protein including their joint interaction, our work introduces possible applications of CPS in bioanalysis of protein complexes, including those relatively unstable, but important in the cancer research.
- MeSH
- Adsorption MeSH
- Protein Structure, Quaternary MeSH
- Humans MeSH
- Models, Molecular MeSH
- Mucoproteins chemistry MeSH
- Protein Multimerization * MeSH
- Neoplasm Proteins chemistry MeSH
- Oncogene Proteins chemistry MeSH
- Protein Domains MeSH
- Carrier Proteins chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Development of a chromatographic method in bioanalysis is a challenging and complex procedure with many pitfalls and often unexpected reversals that can require several months to accomplish. Even an experienced analytical team must contend many limitations mainly in connection with the strict requirements imposed on current clinical research. These restrictions typically persist throughout the whole development process, from clinical trial assignment, across optimization of extraction of biological materials and chromatographic separation, to validation and data interpretation. This paper describes questions and their possible answers raised during the pre-analytical phase such as use of modern sample preparation techniques in clinical methods, application of internal standards, as well as selection of stationary phases and detection techniques in the analytical phase. Validation problems and interpretation of results are demonstrated with three typical examples of characteristics to be considered, i.e. recovery, matrix effect, and limit of detection vs. lower limit of quantification.
- MeSH
- Biological Assay instrumentation methods MeSH
- Chromatography instrumentation methods MeSH
- Humans MeSH
- Limit of Detection MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
The development of clinically applicable portable sensors and multiplex protein biomarker assays is one of the most important goals of laboratory medicine today. Sensing strategies based on electrochemical devices are discussed in this overview, with special emphasis on detection principles derived from voltammetry, electrogenerated chemiluminescence, bipolar electrochemistry and impedance-based measurements. Up-to-date examples of electrochemical methods in biomedical research and development are highlighted here, including critical evaluation and future directions of the analysis, development and validation of new protein biomarkers.
- MeSH
- Biomarkers analysis MeSH
- Biosensing Techniques methods MeSH
- Electrochemical Techniques methods MeSH
- Humans MeSH
- Microarray Analysis methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Resistive pulse sensing is a well-known and established method for counting and sizing particles in ionic solutions. Throughout its development the technique has been expanded from detection of biological cells to counting nanoparticles and viruses, and even registering individual molecules, e.g., nucleotides in nucleic acids. This technique combined with microfluidic or nanofluidic systems shows great potential for various bioanalytical applications, which were hardly possible before microfabrication gained the present broad adoption. In this review, we provide a comprehensive overview of microfluidic designs along with electrode arrangements with emphasis on applications focusing on bioanalysis and analysis of single cells that were reported within the past five years.
- MeSH
- Single-Cell Analysis instrumentation MeSH
- Equipment Design MeSH
- Electrodes MeSH
- Humans MeSH
- Microfluidic Analytical Techniques instrumentation MeSH
- Particle Size MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
AIM: To demonstrate and discuss the pros and cons of various conventional and innovative analytical approaches. Methodology & results: Matrix-assisted laser desorption/ionization mass spectrometry imaging (MSI) of tissue sections as well as the extraction of tissue homogenates, blood plasma and dried blood spots coupled with LC-MS were employed to monitor the pharmacokinetics of metformin in mice. The time profile of metformin measured by matrix-assisted laser desorption/ionization MSI correlated well with the results found by LC-MS. Repeatability of the preparation of tissue sections for MSI was very good. CONCLUSION: MSI provided valuable information on the spatial distribution and relative concentration of the analyte within tissue sections. The analysis of the extracts of tissue homogenates, blood plasma and blood spots provided quantitative data on metformin. The dried blood spot approach is a progressive method of sampling, especially in studies where the amount of available blood is limited.
- MeSH
- Chromatography, Liquid methods MeSH
- Humans MeSH
- Metformin pharmacokinetics MeSH
- Mice MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods MeSH
- Tandem Mass Spectrometry methods MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
This review is a Part II of the series aiming to provide comprehensive overview of currently used antiviral drugs and to show modern approaches to their analysis. While in the Part I antivirals against herpes viruses and antivirals against respiratory viruses were addressed, this part concerns antivirals against hepatitis viruses (B and C) and human immunodeficiency virus (HIV). Many novel antivirals against hepatitis C virus (HCV) and HIV have been introduced into the clinical practice over the last decade. The recent broadening portfolio of these groups of antivirals is reflected in increasing number of developed analytical methods required to meet the needs of clinical terrain. Part II summarizes the mechanisms of action of antivirals against hepatitis B virus (HBV), HCV, and HIV, their use in clinical practice, and analytical methods for individual classes. It also provides expert opinion on state of art in the field of bioanalysis of these drugs. Analytical methods reflect novelty of these chemical structures and use by far the most current approaches, such as simple and high-throughput sample preparation and fast separation, often by means of UHPLC-MS/MS. Proper method validation based on requirements of bioanalytical guidelines is an inherent part of the developed methods.
- MeSH
- Antiviral Agents analysis pharmacology therapeutic use MeSH
- Biological Factors analysis metabolism MeSH
- Hepatitis drug therapy metabolism MeSH
- HIV Infections drug therapy metabolism MeSH
- HIV-1 drug effects metabolism MeSH
- Humans MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
The new microextraction technique named parallel artificial liquid membrane extraction (PALME) was introduced as an alternative approach to liquid-liquid extraction of charged analytes from aqueous samples. The concept is based on extraction of analytes across a supported liquid membrane sustained in the pores of a thin polymeric membrane, a well-known extraction principle also used in hollow fiber liquid-phase microextraction (HF-LPME). However, the new PALME technique offers a more user-friendly setup in which the supported liquid membrane is incorporated in a 96 well plate system. Thus, high-throughput is achievable, in addition to the green chemistry offered by using PALME. The consumption of organic solvent is minimized to 3-5μL per sample. With a sample volume of 250μL and acceptor solution volume of 50μL, a maximal enrichment factor of five is achievable. Based on these parameters, a new method for extraction of polar basic drugs was developed in the present work. The basic drugs hydralazine, ephedrine, metaraminol, salbutamol, and cimetidine were used as model analytes, and were extracted from alkalized human plasma into an aqueous solution via the supported liquid membrane. The extraction was promoted by a carrier dissolved in the membrane, creating a temporary ion-pair complex between the hydrophilic drug and the carrier. As the model analytes were extracted directly into an aqueous solution, there was no need for evaporation of the extract before injection into LC-MS. Hence, the sample preparation is performed in one step. With optimized conditions, the extraction recoveries were in the range 50-89% from human plasma after 45min extraction. The data from the method evaluation were satisfactory and in line with current guidelines, and revealed an extraction method with substantial potential for high throughput bioanalysis of polar basic drugs.
- MeSH
- Chromatography, Liquid methods MeSH
- Liquid-Liquid Extraction methods MeSH
- Mass Spectrometry methods MeSH
- Pharmaceutical Preparations blood chemistry isolation & purification MeSH
- Humans MeSH
- Limit of Detection MeSH
- Linear Models MeSH
- Membranes, Artificial * MeSH
- Reproducibility of Results MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
