A review is presented on the state of the art of the chemiluminescence analysis of pharmaceuticals by the two most relevant automated controlled-flow methodologies--flow-injection analysis (FIA) and sequential-injection analysis (SIA). The current chemiluminometric applications of FIA and SIA in pharmaceutical analysis are discussed with special emphasis on the analytical figures of merit and sample matrix characteristics. The review involving 211 references and covering papers published between 2001 and 2006 is divided into several sections according to the fundamental types of chemiluminescence systems employed.
- MeSH
- Pharmaceutical Preparations analysis MeSH
- Luminescent Measurements methods MeSH
- Oxidation-Reduction MeSH
- Flow Injection Analysis MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Names of Substances
- Pharmaceutical Preparations MeSH
We report the first amperometric method for the simultaneous determination of tert-butylhydroquinone (tBHQ), propyl gallate (PG), and butylated hydroxyanisole (BHA) using flow injection analysis coupled to multiple-pulse amperometry. A sequence of potential pulses was selected in order to detect tBHQ, PG, and BHA separately in a single injection step at a glassy carbon electrode without the need of a preliminary separation. A mixture of methanol and 0.040M Britton-Robinson buffer was used both as a carrier solution and for dilution of analyzed solutions before injection. The method is precise (RSD < 5%, n = 10), fast (a frequency of 140 injections h-1), provides sufficiently low quantification limits (2.51, 1.45, and 0.85μmolL-1 for tBHQ, PG, and BHA, respectively) and can be easily applied without high demands on instrumentation. As a practical application, the determination of these antioxidants contained in commercial chewing gum samples was carried out by applying a simple extraction procedure.
- Keywords
- Antioxidants, Flow injection analysis, Glassy carbon electrode, Multiple-pulse amperometry,
- MeSH
- Butylated Hydroxyanisole analysis MeSH
- Time Factors MeSH
- Electrochemistry instrumentation methods MeSH
- Electrodes MeSH
- Hydroquinones analysis MeSH
- Propyl Gallate analysis MeSH
- Flow Injection Analysis * MeSH
- Chewing Gum analysis MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- 2-tert-butylhydroquinone MeSH Browser
- Butylated Hydroxyanisole MeSH
- Hydroquinones MeSH
- Propyl Gallate MeSH
- Chewing Gum MeSH
Direct infusion of lipid extracts into the ion source of a mass spectrometer is a well-established method for lipid analysis. In most cases, nanofluidic devices are used for sample introduction. However, flow injection analysis (FIA) based on sample infusion from a chromatographic pump can offer a simple alternative to shotgun-based approaches. Here, we describe important modification of a method based on FIA and tandem mass spectrometry (MS/MS). We focus on minimizing contamination of the FIA/MS both to render the lipidomic platform more robust and to increase its capacity and applicability for long-sequence measurements required in clinical applications. Robust validation of the developed method confirms its suitability for lipid quantitation in human plasma analysis. Measurements of standard human plasma reference material (NIST SRM 1950) and a set of plasma samples collected from kidney cancer patients and from healthy volunteers yielded highly similar results between FIA-MS/MS and ultra-high-performance supercritical fluid chromatography (UHPSFC)/MS, thereby demonstrating that all modifications have practically no effect on the statistical output. Newly modified FIA-MS/MS allows for the quantitation of 141 lipid species in plasma (11 major lipid classes) within 5.7 min. Finally, we tested the method in a clinical laboratory of the General University Hospital in Prague. In the clinical setting, the method capacity reached 257 samples/day. We also show similar performance of the classification models trained based on the results obtained in clinical settings and the analytical laboratory at the University of Pardubice. Together, these findings demonstrate the high potential of the modified FIA-MS/MS for application in clinical laboratories to measure plasma and serum lipid profiles.
- Keywords
- Direct infusion lipidomics, Flow injection analysis, High-throughput lipidomics, Lipid quantitation, Mass spectrometry, Validation,
- MeSH
- Plasma chemistry MeSH
- Humans MeSH
- Lipidomics * methods MeSH
- Lipids analysis MeSH
- Flow Injection Analysis MeSH
- Tandem Mass Spectrometry * methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Lipids MeSH
The flow-injection method with sensitive fluorimetric detection is used to monitor the liberation profiles of a topical dermatological formulation containing the model compound salicylic acid. The connection of a standard Franz diffusion cell with the automated flow-injection system enables an acquisition of multi-point liberation data in a form of series of fluorescence peaks in a short time. Examples of liberation profiles for a topical dermatological formulation containing salicylic acid are shown.
- MeSH
- Autoanalysis MeSH
- Diffusion MeSH
- Spectrometry, Fluorescence MeSH
- Calibration MeSH
- Hydrogen-Ion Concentration MeSH
- Salicylic Acid analysis MeSH
- Pharmaceutical Preparations analysis MeSH
- Ointments MeSH
- Flow Injection Analysis methods MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Salicylic Acid MeSH
- Pharmaceutical Preparations MeSH
- Ointments MeSH
A simple and inexpensive flow injection-capillary electrophoresis (FI-CE) system with contactless conductivity detection (CCD) for automated quantitative analysis of chloride, nitrate, and sulfate in various water samples is demonstrated. A glass bottle containing the background electrolyte that is raised above the FI-CE interface generates a pulse-free, highly reproducible flow of the electrolyte through the FI-CE interface. The system operates at a flow rate of 300 microLmin(-1) with an injection volume of only 4 microL. The repeatability of peak areas (n = 18) was better than 0.81% RSD and the sample throughput was 90 samples per hour using the background electrolyte containing 12 mM L-histidine adjusted to pH 4.00 with acetic acid. The limits of detection were better than 125 microgL(-1) and were comparable to those obtained by conventional CE systems with CCD. Various calibration methods for FI-CE system with electrokinetic injection were tested and their suitability for the analysis of anions in real samples was evaluated.
- MeSH
- Anions MeSH
- Inorganic Chemicals isolation & purification MeSH
- Electrophoresis, Capillary methods MeSH
- Calibration MeSH
- Flow Injection Analysis methods MeSH
- Reproducibility of Results MeSH
- Pressure MeSH
- Water chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Anions MeSH
- Inorganic Chemicals MeSH
- Water MeSH
An amperometric biosensor compatible with a flow injection analysis (FIA) for highly selective determination of acetaminophen (APAP) in a sample of human urine was developed. This biosensor is also suitable for use in the routine pharmaceutical practice. To prove this statement, two different commercially available pharmaceutical formulations were analyzed. This nano-(bio)electroanalytical device was made from a commercially available screen-printed carbon electrode covered by a thin layer of non-functionalized graphene (NFG) as amperometric transducer. A biorecognition layer was prepared from mushroom (Agaricus bisporus) tyrosinase (EC 1.14.18.1) cross-linked using glutaraldehyde, where resulting aggregates were covered by Nafion®, a known ion exchange membrane. Owing to the use of tyrosinase and presence of NFG, the developed analytical instrument is able to measure even at potentials of 0 V. Linear ranges differ according to choice of detection potential, namely up to 130 μmol L-1 at 0 V, up to 90 μmol L-1 at -0.1 V, and up to 70 μmol L-1 at -0.15 V. The first mentioned linear range is described by the equation Ip [μA] = 0.236 - 0.1984c [μmol L-1] and correlation coefficient r = 0.9987; this equation was used to quantify the content of APAP in each sample. The limit of detection of APAP was estimated to be 1.1 μmol L-1. A recovery of 96.8% (c = 25 μmol L-1, n = 5 measurements) was calculated. The obtained results show that FIA is a very selective method for APAP determination, being comparable to the chosen reference method of reversed-phase high-performance liquid chromatography.
- Keywords
- Acetaminophen, Amperometry, Biosensor, Flow injection analysis, Human urine, Tyrosinase,
- MeSH
- Agaricus enzymology MeSH
- Urinalysis instrumentation methods MeSH
- Biosensing Techniques instrumentation methods MeSH
- Equipment Design MeSH
- Humans MeSH
- Limit of Detection MeSH
- Analgesics, Non-Narcotic urine MeSH
- Acetaminophen urine MeSH
- Flow Injection Analysis instrumentation methods MeSH
- Monophenol Monooxygenase chemistry MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Names of Substances
- Analgesics, Non-Narcotic MeSH
- Acetaminophen MeSH
- Monophenol Monooxygenase MeSH
A new method for the simultaneous determination of two tumour biomarkers, homovanillic (HVA) and vanillylmandelic acid (VMA), using flow injection analysis (FIA) with amperometric detection (AD) at a commercially available boron doped diamond electrode (BDDE) was developed. It was found that this method is suitable for the determination of HVA (in the presence of VMA) and VMA (in the presence of HVA) in optimum medium of Britton-Robinson buffer (0.04 mol L-1, pH 3.0). Calibration dependences consist of two linear parts for both biomarkers, the first one being in the concentration range from 1 to 10 μmol L-1 and the second one from 10 to 100 μmol L-1 (with obtained LODs 0.44 μmol L-1 for HVA and 0.34 μmol L-1 for VMA, respectively). To minimize any negative effects related to the passivation of the working electrode, suitable cleaning pulses (+2.4 V for 30 s) were imposed on the working electrode after each measurement. An attempt to use FIA with multiple pulse amperometric detection to determine both analytes in one run was not successful. Changing potentials in short intervals in multiple pulse detection probably results in mutual interaction of analytes and/or products of their electrochemical oxidation, thus preventing the application of this approach.
- Keywords
- Boron doped diamond electrode, Flow injection analysis, Homovanillic acid, Tumour biomarkers, Vanillylmandelic acid,
- MeSH
- Boron chemistry MeSH
- Diamond chemistry MeSH
- Electrochemical Techniques instrumentation methods MeSH
- Electrodes MeSH
- Homovanillic Acid analysis chemistry MeSH
- Vanilmandelic Acid analysis chemistry MeSH
- Limit of Detection MeSH
- Biomarkers, Tumor analysis chemistry MeSH
- Oxidation-Reduction MeSH
- Flow Injection Analysis methods MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Boron MeSH
- Diamond MeSH
- Homovanillic Acid MeSH
- Vanilmandelic Acid MeSH
- Biomarkers, Tumor MeSH
Platinum-based cytostatics, such as cisplatin, carboplatin or oxaliplatin are widely used agents in the treatment of various types of tumors. Large amounts of these drugs are excreted through the urine of patients into wastewaters in unmetabolised forms. This phenomenon leads to increased amounts of platinum ions in the water environment. The impacts of these pollutants on the water ecosystem are not sufficiently investigated as well as their content in water sources. In order to facilitate the detection of various types of platinum, we have developed a new, rapid, screening flow injection analysis method with electrochemical detection (FIA-ED). Our method, based on monitoring of the changes in electrochemical behavior of analytes, maintained by various pH buffers (Britton-Robinson and phosphate buffer) and potential changes (1,000, 1,100 and 1,200 mV) offers rapid and cheap selective determination of platinum-based cytostatics and platinum chlorides, which can also be present as contaminants in water environments.
- MeSH
- Water Pollutants, Chemical analysis urine MeSH
- Platinum analysis urine MeSH
- Antineoplastic Agents analysis urine MeSH
- Flow Injection Analysis MeSH
- Platinum Compounds analysis urine MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Water Pollutants, Chemical MeSH
- Platinum MeSH
- platinum chloride MeSH Browser
- Antineoplastic Agents MeSH
- Platinum Compounds MeSH
The method for automatic continual monitoring of acetylcholinesterase (AChE) activity in biological material is described. It is based on flexible system of plastic pipes mixing samples of biological material with reagents for enzyme determination; reaction product penetrates through the semipermeable membrane and it is spectrophotometrically determined (Ellman's method). It consists of sampling (either in vitro or in vivo), adding the substrate and flowing to dialyzer; reaction product (thiocholine) is dialyzed and mixed with 5,5'-dithio-bis-2-nitrobenzoic acid (DTNB) transported to flow spectrophotometer. Flowing of all materials is realised using peristaltic pump. The method was validated: time for optimal hydratation of the cellophane membrane; type of the membrane; type of dialyzer; conditions for optimal permeation of reaction components; optimization of substrate and DTNB concentrations (linear dependence); efficacy of peristaltic pump; calibration of analytes after permeation through the membrane; excluding of the blood permeation through the membrane. Some examples of the evaluation of the effects of AChE inhibitors are described. It was demonstrated very good uniformity of peaks representing the enzyme activity (good reproducibility); time dependence of AChE inhibition caused by VX in vitro in the rat blood allowing to determine the half life of inhibition and thus, bimolecular rate constants of inhibition; reactivation of inhibited AChE by some reactivators, and continual monitoring of the activity in the whole blood in vivo in intact and VX-intoxicated rats. The method is simple and not expensive, allowing automatic determination of AChE activity in discrete or continual samples in vitro or in vivo. It will be evaluated for further research of cholinesterase inhibitors.
- MeSH
- Acetylcholinesterase blood metabolism MeSH
- Cholinesterase Inhibitors pharmacology MeSH
- Enzyme Assays instrumentation methods MeSH
- Kinetics MeSH
- Rats MeSH
- Dithionitrobenzoic Acid metabolism MeSH
- Membranes, Artificial MeSH
- Flow Injection Analysis instrumentation methods MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Acetylcholinesterase MeSH
- Cholinesterase Inhibitors MeSH
- Dithionitrobenzoic Acid MeSH
- Membranes, Artificial MeSH
The present review dealing with the use of various electrochemical detection systems in flow methods of analysis of drugs (such as FIA and SIA techniques). The review covers the period of 1988 to 1998 and involves 78 references. The drugs determined are arranged according to the functional groups undergoing electrochemical transformation; for all the analytes data on the detection conditions, detection limits and ranges of quantitation are included. Advantages and drawbacks of amperometric detection of drugs in flow systems are discussed.
- MeSH
- Electrochemistry methods MeSH
- Pharmaceutical Preparations analysis MeSH
- Flow Injection Analysis * methods MeSH
- Publication type
- English Abstract MeSH
- Journal Article MeSH
- Names of Substances
- Pharmaceutical Preparations MeSH
