International Journal of Molecular Sciences, May 24, 2018
The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of var... more The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of various central nervous system (CNS) pathologies has been demonstrated. Knowing that NTs-related diseases mostly occupy individual regions of the nervous system, as observed, for instance, in neurodegenerative diseases (Alzheimer's and Parkinson's Diseases), the analysis of brain slices is preferred to whole-brain analysis. In this report, we present sample preparation approaches, such as solid-phase extraction, solid-phase microextraction, and dispersive liquid-liquid microextraction, and discuss the pitfalls and advantages of each extraction method. The ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate)-assisted solid-phase microextraction (IL-SPME) is found to be, in our research, the relevant step towards the simultaneous determination of six NTs, namely, dopamine (DA), adrenaline (A), noradrenaline (NA), serotonin (5-HT), L-tryptophan (L-Trp), L-tyrosine (L-Tyr) in rat brain samples. The development of a novel bioanalytical technique for the evaluation of biomarkers in the context of green chemistry might be accelerated just with the use of IL, and this approach can be considered an advantageous strategy.
Small Molecules Originated from Tryptophan and their Clinical Significance as Potential Biomarkers
Combinatorial Chemistry & High Throughput Screening
Background: L-tryptophan is an essential amino acid, necessary for the human body to function. It... more Background: L-tryptophan is an essential amino acid, necessary for the human body to function. Its degradation occurs through two metabolic pathways. Approximately 95% of the L-tryptophan available in the body is converted via the kynurenine pathway, while the remainder is degraded via the serotonin pathway. Properly maintained balance between the concentrations of individual small molecular metabolites is extremely important to maintain homeostasis in the human body, and its disruption could lead to the development of numerous neurological, neurodegenerative, neoplastic, as well as cardiovascular diseases. Recent reports suggested that by controlling the levels of selected L-tryptophan metabolites (potential biomarkers), it is possible to diagnose numerous diseases, monitor their course and assess patient prognosis. Objective: The aim of this paper is to review the currently important clinical applications of selected biomarkers from the L-tryptophan metabolism pathways that would ...
Lead (Pb) was revealed for its role as a neurodevelopmental toxin. The determination of neurotran... more Lead (Pb) was revealed for its role as a neurodevelopmental toxin. The determination of neurotransmitters (NTs) in particular brain regions could ameliorate the precise description and optimization of therapeutic protocols able to restore the harmony of signaling pathways in nervous and immune systems. The determination of selected analytes from the group of NTs based on the liquid chromatography (LC)-based method was carried out to illustrate the changes of amino acid (AA) and biogenic amine (BA) profiles observed in chosen immune and nervous systems rat tissues after Pb intoxication. Also, a protective combination of AA was proposed to correct the changes caused by Pb intoxication. After the administration of Pb, changes were observed in all organs studied and were characterized by a fluctuation of NT concentrations in immune and nervous systems (hypothalamus samples). Using a protective mixture of bioactive compounds prevented numerous changes in the balance of NT. The combined a...
Extraction and preconcentration of compounds from the l-tyrosine metabolic pathway prior to their micellar electrokinetic chromatography separation
Journal of Chromatography A
The prominent biological effects of adrenaline (A), noradrenaline (NA) and dopamine (DA) as well ... more The prominent biological effects of adrenaline (A), noradrenaline (NA) and dopamine (DA) as well as the clinical importance of their metabolites (such as dihydroxyphenylacetic acid (DOPAC), methoxy‑4-hydroxyphenyl glycol (MHPG), dihydroxyphenylglycol (DHPG), metanephrine (M), normetanephrine (NM), vanillylmandelic acid (VMA), homovanillic acid (HVA)) have forced researchers to evaluate new analytical methodologies for their isolation and preconcentration from biological samples. For this reason, the three most popular extraction techniques (dispersive liquid-liquid microextraction (DLLME), solid-phase extraction (SPE), solid-phase microextraction (SPME)) were tested. Micellar electrokinetic chromatography (MEKC) - a mode of capillary electrophoresis - with a diode array detector (DAD) was applied to assess the extraction efficiency. Next, the enrichment factor (EF) of each applied method was calculated in respect to standard mixtures of the analytes at the same concentration levels. The EF results of seven selected metabolites of biogenic amines (BAs) from urine after sample preparation procedures based on twenty-five different protocols (one DLLME, thirteen SPE and eleven SPME) were calculated and compared using hierarchical cluster analysis (HCA). The SPE as well as SPME procedures were proved to be the most effective approaches for the simultaneous extraction of the chosen compounds. Moreover, an ionic liquid (IL) - 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide - added to methanol in SPME additionally could successfully improve the extraction efficiency. It was also confirmed that the HCA approach could be considered a supportive tool in the selection of a suitable sample preparation procedure for that group of endogenous substances.
Optimization and comparison of two microsampling approaches for LC-MS/MS analysis of a panel of immunosuppressants in blood samples
Sustainable Chemistry and Pharmacy
Abstract Immunosuppressive drugs have commonly been used to prevent transplant rejection, and rec... more Abstract Immunosuppressive drugs have commonly been used to prevent transplant rejection, and recently, also in pharmacotherapy of patients with coronary stents. Due to low level of those drugs in biological fluids and their significant distribution into erythrocytes, sample preparation steps are critical for the determination and monitoring of these drugs in complex biomatrices, especially in whole blood. In this study, two modern and environmentally friendly microextraction strategies—namely, solid-phase microextraction (SPME) and dispersive liquid-liquid microextraction (DLLME)—are optimized and compared with respect to their extraction efficiencies for four immunosuppressants (tacrolimus, TAC; novolimus, NOV; everolimus, EVE; sirolimus, SIR) in serum and whole blood samples. Analyte separation was carried out using a Kinetex® C18 column (50 × 2.1 mm, 1.7 μm) thermostated at 55 °C, and analyses were performed in positive ion mode with a total analysis time of 6.5 min. The results revealed that, while the optimized SPME and DLLME protocols showed similar efficiency for the extraction of TAC, SIR, and EVE from biofluids, the DLLME protocol exhibited significantly better performance for the extraction of the novel immunosuppressive drug, NOV. Therefore, DLLME using ethanol (dispersive solvent) and chloroform (extraction solvent) in a ratio of 800/200 (v/v) was selected for further studies. The final optimized DLLME-LC-MS/MS conditions enabled a limit of quantitation of 1 ng/mL for TAC, 2.5 ng/mL for SIR and EVE, and 25 ng/mL for NOV. The results presented herein demonstrate that the proposed method can be successfully applied for the analysis of selected immunosuppressants in real samples during pharmacokinetic studies and therapeutic monitoring.
The critical evaluation of the effects of imidazolium-based ionic liquids on the separation efficiency of selected biogenic amines and their metabolites during MEKC analysis
The tumor microenvironment (TME) consists of numerous biologically relevant elements. One of the ... more The tumor microenvironment (TME) consists of numerous biologically relevant elements. One of the most important components of the TME is the extracellular matrix (ECM). The compounds of the ECM create a network that provides structural and biochemical support to surrounding cells. The most important substances involved in the regulation of the ECM degradation process are matrix metalloproteinases (MMPs) and their endogenous inhibitors (tissue inhibitors of metalloproteinases, TIMPs). The disruption of the physiological balance between MMP activation and deactivation could lead to progression of various diseases such as cardiovascular disease, cancer, fibrosis arthritis, chronic tissue ulcers, pathologies of the nervous system (such as stroke and Alzheimer’s disease), periodontitis, and atheroma. MMP-TIMP imbalance results in matrix proteolysis associated with various pathological processes such as tumor invasion. The present review discusses the involvement of two MMPs, MMP-2 and MM...
The broad spectrum of the mechanism of action of immune-boosting natural compounds as well as the... more The broad spectrum of the mechanism of action of immune-boosting natural compounds as well as the complex nature of the food matrices make researching the health benefits of various food products a complicated task. Moreover, many routes are involved in the action of most natural compounds that lead to the inhibition of chronic inflammation, which results in a decrease in the ability to remove a pathogen asymptomatically and is connected to various pathological events, such as cancer. A number of cancers have been associated with inflammatory processes. The current review strives to answer the question of whether plant-derived sulfur compounds could be beneficial in cancer prevention and therapy. This review focuses on the two main sources of natural sulfur compounds: alliaceous and cruciferous vegetables. Through the presentation of scientific data which deal with the study of the chosen compounds in cancer (cell lines, animal models, and human studies), the discussion of food proc...
Ionic Liquids, Microextraction Methods and Capillary Electrophoresis in Biomedical Research
Current Pharmaceutical Analysis
:: The review aims to present the importance of implementing microextraction-, capillary electrop... more :: The review aims to present the importance of implementing microextraction-, capillary electrophoresis- and ionic liquid-based approaches in biomedical research. These analytical strategies could improve the biochemical diagnosis of various life-threatening diseases, aid in the search for therapeutic agents and the discovery of drug targets and could be used when designing newer, safer medicinal products. All the proposed analytical approaches meet the requirements of “green chemistry”-based methods, which is relevant nowadays in view of the pollution of the Earth becoming a serious problem. The review is divided into three main sections, and biomedical examples of the application of each presented approach are discussed. It is assumed that the undoubted advantages of ionic liquid-, microextraction- and capillary electrophoresis-based methods will speed up their use in the study of various clinically important analytes from different biological fluids and tissue samples.
Multiple reviews have been published on various aspects of carotenoid extraction. Nevertheless, n... more Multiple reviews have been published on various aspects of carotenoid extraction. Nevertheless, none of them focused on the discussion of recent green chemistry extraction protocols, especially for the carotenoids extraction from Daucus carota L. This group of bioactive compounds has been chosen for this review since most of the scientific papers proved their antioxidant properties relevant for inflammation, stress-related disorders, cancer, or neurological and neurodegenerative diseases, such as stroke and Alzheimer’s Disease. Besides, carrots constitute one of the most popular sources of carotenoids. In the presented review emphasis has been placed on the supercritical carbon dioxide and enzyme-assisted extraction techniques for the relevant tetraterpenoids. The detailed descriptions of these methods, as well as practical examples, are provided. In addition, the pros and cons of each method and comparison with the standard solvent extraction have been discussed.
A new approach for the sensitive, robust and rapid determination of idarubicin (IDA) in human pla... more A new approach for the sensitive, robust and rapid determination of idarubicin (IDA) in human plasma and urine samples based on liquid chromatography with fluorescence detection (LC-FL) was developed. Satisfactory chromatographic separation of the analyte after solid-phase extraction (SPE) was performed on a Discovery HS C18 analytical column using a mixture of acetonitrile and 0.1% formic acid in water as the mobile phase in isocratic mode. IDA and daunorubicin hydrochloride used as an internal standard (I.S.) were monitored at the excitation and emission wavelengths of 487 and 547 nm, respectively. The method was validated according to the FDA and ICH guidelines. The linearity was confirmed in the range of 0.1–50 ng/mL and 0.25–200 ng/mL, while the limit of detection (LOD) was 0.05 and 0.125 ng/mL in plasma and urine samples, respectively. The developed LC-FL method was successfully applied for drug determinations in human plasma and urine after oral administration of IDA at a dos...
Development and validation of a high-performance liquid chromatographic method with a fluorescence detector for the analysis of epirubicin in human urine and plasma, and its application in drug monitoring
Biogenic amines (BAs) are bioactive endogenous compounds which play a significant physiological r... more Biogenic amines (BAs) are bioactive endogenous compounds which play a significant physiological role in many cell processes like cell proliferation and differentiation, signal transduction and membrane stability. Likewise, they are important in the regulation of body temperature, the increase/decrease of blood pressure or intake of nutrition, as well as in the synthesis of nucleic acids and proteins, hormones and alkaloids. Additionally, it was confirmed that these compounds can be considered as useful biomarkers for the diagnosis, therapy and prognosis of several neuroendocrine and cardiovascular disorders, including neuroendocrine tumours (NET), schizophrenia and Parkinson’s Disease. Due to the fact that BAs are chemically unstable, light-sensitive and possess a high tendency for spontaneous oxidation and decomposition at high pH values, their determination is a real challenge. Moreover, their concentrations in biological matrices are extremely low. These issues make the measureme...
Practical Application of Biogenic Amine Profiles for the Diagnosis of Patients with Ischemic Stroke
Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association, 2018
Ischemic stroke (IS) is still one of the major issues in medicine. Still, early diagnosis and mis... more Ischemic stroke (IS) is still one of the major issues in medicine. Still, early diagnosis and misdiagnosis remain the main barriers for proper patient treatment and follow-up. Exploring new potential diagnostic biomarkers for IS is relevant to decrease patient morbidity and the occurrence of poststroke diseases. Biomedical analysis could bring new light to the background of IS and-in such a way-propose new bioanalytical tools for the early diagnosis, prognostication, and monitoring of IS. This research aimed to present a discussion on the employment of biogenic amines (BAs), as well as their precursory amino acids and main metabolites, as a new panel of biomarkers for IS. Preliminary patient data were presented and the patients were described with respect to their clinical history and examination records, as well as scientific data gained from the liquid extraction-capillary electrophoresis determination of BAs in the patients' urine samples. The results showed the potential of ...
International journal of molecular sciences, Jan 24, 2018
The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of var... more The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of various central nervous system (CNS) pathologies has been demonstrated. Knowing that NTs-related diseases mostly occupy individual regions of the nervous system, as observed, for instance, in neurodegenerative diseases (Alzheimer’s and Parkinson’s Diseases), the analysis of brain slices is preferred to whole-brain analysis. In this report, we present sample preparation approaches, such as solid-phase extraction, solid-phase microextraction, and dispersive liquid⁻liquid microextraction, and discuss the pitfalls and advantages of each extraction method. The ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate)-assisted solid-phase microextraction (IL-SPME) is found to be, in our research, the relevant step towards the simultaneous determination of six NTs, namely, dopamine (DA), adrenaline (A), noradrenaline (NA), serotonin (5-HT), l-tryptophan (l-Trp), l-tyrosine (l-Tyr) i...
Simultaneous electrokinetic and hydrodynamic injection and sequential stacking featuring sweeping for signal amplification following MEKC during the analysis of rapamycin (sirolimus) in serum samples
Electrophoresis, 2018
Simultaneous electrokinetic and hydrodynamic injection of rapamycin (sirolimus) with off-line and... more Simultaneous electrokinetic and hydrodynamic injection of rapamycin (sirolimus) with off-line and online sample preconcentration techniques and using MEKC has been studied. Compared to conventional hydrodynamic injection, a 168-fold improvement in the signal was obtained with a combination of simultaneous electrokinetic and hydrodynamic injectionand field enhanced sample injection in conjunction with a sweeping technique called sequential stacking featuring sweeping. However, the coupling of the developed electrophoretic method and solid-phase microextraction allowed the signal intensity to increase more than 231 times. In this approach, the injection of the sample at negative polarity (anode at the detector end) into the capillary and the MEKC separation was achieved within 5 min using an electrolyte (composed of 10 mM sodium tetraborate and 40 mM SDS) when ultraviolet (UV) detection was performed at 280 nm. Thus, by combining the application of the sequential stacking featuring sw...
International Journal of Molecular Sciences, May 24, 2018
The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of var... more The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of various central nervous system (CNS) pathologies has been demonstrated. Knowing that NTs-related diseases mostly occupy individual regions of the nervous system, as observed, for instance, in neurodegenerative diseases (Alzheimer's and Parkinson's Diseases), the analysis of brain slices is preferred to whole-brain analysis. In this report, we present sample preparation approaches, such as solid-phase extraction, solid-phase microextraction, and dispersive liquid-liquid microextraction, and discuss the pitfalls and advantages of each extraction method. The ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate)-assisted solid-phase microextraction (IL-SPME) is found to be, in our research, the relevant step towards the simultaneous determination of six NTs, namely, dopamine (DA), adrenaline (A), noradrenaline (NA), serotonin (5-HT), L-tryptophan (L-Trp), L-tyrosine (L-Tyr) in rat brain samples. The development of a novel bioanalytical technique for the evaluation of biomarkers in the context of green chemistry might be accelerated just with the use of IL, and this approach can be considered an advantageous strategy.
Small Molecules Originated from Tryptophan and their Clinical Significance as Potential Biomarkers
Combinatorial Chemistry & High Throughput Screening
Background: L-tryptophan is an essential amino acid, necessary for the human body to function. It... more Background: L-tryptophan is an essential amino acid, necessary for the human body to function. Its degradation occurs through two metabolic pathways. Approximately 95% of the L-tryptophan available in the body is converted via the kynurenine pathway, while the remainder is degraded via the serotonin pathway. Properly maintained balance between the concentrations of individual small molecular metabolites is extremely important to maintain homeostasis in the human body, and its disruption could lead to the development of numerous neurological, neurodegenerative, neoplastic, as well as cardiovascular diseases. Recent reports suggested that by controlling the levels of selected L-tryptophan metabolites (potential biomarkers), it is possible to diagnose numerous diseases, monitor their course and assess patient prognosis. Objective: The aim of this paper is to review the currently important clinical applications of selected biomarkers from the L-tryptophan metabolism pathways that would ...
Lead (Pb) was revealed for its role as a neurodevelopmental toxin. The determination of neurotran... more Lead (Pb) was revealed for its role as a neurodevelopmental toxin. The determination of neurotransmitters (NTs) in particular brain regions could ameliorate the precise description and optimization of therapeutic protocols able to restore the harmony of signaling pathways in nervous and immune systems. The determination of selected analytes from the group of NTs based on the liquid chromatography (LC)-based method was carried out to illustrate the changes of amino acid (AA) and biogenic amine (BA) profiles observed in chosen immune and nervous systems rat tissues after Pb intoxication. Also, a protective combination of AA was proposed to correct the changes caused by Pb intoxication. After the administration of Pb, changes were observed in all organs studied and were characterized by a fluctuation of NT concentrations in immune and nervous systems (hypothalamus samples). Using a protective mixture of bioactive compounds prevented numerous changes in the balance of NT. The combined a...
Extraction and preconcentration of compounds from the l-tyrosine metabolic pathway prior to their micellar electrokinetic chromatography separation
Journal of Chromatography A
The prominent biological effects of adrenaline (A), noradrenaline (NA) and dopamine (DA) as well ... more The prominent biological effects of adrenaline (A), noradrenaline (NA) and dopamine (DA) as well as the clinical importance of their metabolites (such as dihydroxyphenylacetic acid (DOPAC), methoxy‑4-hydroxyphenyl glycol (MHPG), dihydroxyphenylglycol (DHPG), metanephrine (M), normetanephrine (NM), vanillylmandelic acid (VMA), homovanillic acid (HVA)) have forced researchers to evaluate new analytical methodologies for their isolation and preconcentration from biological samples. For this reason, the three most popular extraction techniques (dispersive liquid-liquid microextraction (DLLME), solid-phase extraction (SPE), solid-phase microextraction (SPME)) were tested. Micellar electrokinetic chromatography (MEKC) - a mode of capillary electrophoresis - with a diode array detector (DAD) was applied to assess the extraction efficiency. Next, the enrichment factor (EF) of each applied method was calculated in respect to standard mixtures of the analytes at the same concentration levels. The EF results of seven selected metabolites of biogenic amines (BAs) from urine after sample preparation procedures based on twenty-five different protocols (one DLLME, thirteen SPE and eleven SPME) were calculated and compared using hierarchical cluster analysis (HCA). The SPE as well as SPME procedures were proved to be the most effective approaches for the simultaneous extraction of the chosen compounds. Moreover, an ionic liquid (IL) - 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide - added to methanol in SPME additionally could successfully improve the extraction efficiency. It was also confirmed that the HCA approach could be considered a supportive tool in the selection of a suitable sample preparation procedure for that group of endogenous substances.
Optimization and comparison of two microsampling approaches for LC-MS/MS analysis of a panel of immunosuppressants in blood samples
Sustainable Chemistry and Pharmacy
Abstract Immunosuppressive drugs have commonly been used to prevent transplant rejection, and rec... more Abstract Immunosuppressive drugs have commonly been used to prevent transplant rejection, and recently, also in pharmacotherapy of patients with coronary stents. Due to low level of those drugs in biological fluids and their significant distribution into erythrocytes, sample preparation steps are critical for the determination and monitoring of these drugs in complex biomatrices, especially in whole blood. In this study, two modern and environmentally friendly microextraction strategies—namely, solid-phase microextraction (SPME) and dispersive liquid-liquid microextraction (DLLME)—are optimized and compared with respect to their extraction efficiencies for four immunosuppressants (tacrolimus, TAC; novolimus, NOV; everolimus, EVE; sirolimus, SIR) in serum and whole blood samples. Analyte separation was carried out using a Kinetex® C18 column (50 × 2.1 mm, 1.7 μm) thermostated at 55 °C, and analyses were performed in positive ion mode with a total analysis time of 6.5 min. The results revealed that, while the optimized SPME and DLLME protocols showed similar efficiency for the extraction of TAC, SIR, and EVE from biofluids, the DLLME protocol exhibited significantly better performance for the extraction of the novel immunosuppressive drug, NOV. Therefore, DLLME using ethanol (dispersive solvent) and chloroform (extraction solvent) in a ratio of 800/200 (v/v) was selected for further studies. The final optimized DLLME-LC-MS/MS conditions enabled a limit of quantitation of 1 ng/mL for TAC, 2.5 ng/mL for SIR and EVE, and 25 ng/mL for NOV. The results presented herein demonstrate that the proposed method can be successfully applied for the analysis of selected immunosuppressants in real samples during pharmacokinetic studies and therapeutic monitoring.
The critical evaluation of the effects of imidazolium-based ionic liquids on the separation efficiency of selected biogenic amines and their metabolites during MEKC analysis
The tumor microenvironment (TME) consists of numerous biologically relevant elements. One of the ... more The tumor microenvironment (TME) consists of numerous biologically relevant elements. One of the most important components of the TME is the extracellular matrix (ECM). The compounds of the ECM create a network that provides structural and biochemical support to surrounding cells. The most important substances involved in the regulation of the ECM degradation process are matrix metalloproteinases (MMPs) and their endogenous inhibitors (tissue inhibitors of metalloproteinases, TIMPs). The disruption of the physiological balance between MMP activation and deactivation could lead to progression of various diseases such as cardiovascular disease, cancer, fibrosis arthritis, chronic tissue ulcers, pathologies of the nervous system (such as stroke and Alzheimer’s disease), periodontitis, and atheroma. MMP-TIMP imbalance results in matrix proteolysis associated with various pathological processes such as tumor invasion. The present review discusses the involvement of two MMPs, MMP-2 and MM...
The broad spectrum of the mechanism of action of immune-boosting natural compounds as well as the... more The broad spectrum of the mechanism of action of immune-boosting natural compounds as well as the complex nature of the food matrices make researching the health benefits of various food products a complicated task. Moreover, many routes are involved in the action of most natural compounds that lead to the inhibition of chronic inflammation, which results in a decrease in the ability to remove a pathogen asymptomatically and is connected to various pathological events, such as cancer. A number of cancers have been associated with inflammatory processes. The current review strives to answer the question of whether plant-derived sulfur compounds could be beneficial in cancer prevention and therapy. This review focuses on the two main sources of natural sulfur compounds: alliaceous and cruciferous vegetables. Through the presentation of scientific data which deal with the study of the chosen compounds in cancer (cell lines, animal models, and human studies), the discussion of food proc...
Ionic Liquids, Microextraction Methods and Capillary Electrophoresis in Biomedical Research
Current Pharmaceutical Analysis
:: The review aims to present the importance of implementing microextraction-, capillary electrop... more :: The review aims to present the importance of implementing microextraction-, capillary electrophoresis- and ionic liquid-based approaches in biomedical research. These analytical strategies could improve the biochemical diagnosis of various life-threatening diseases, aid in the search for therapeutic agents and the discovery of drug targets and could be used when designing newer, safer medicinal products. All the proposed analytical approaches meet the requirements of “green chemistry”-based methods, which is relevant nowadays in view of the pollution of the Earth becoming a serious problem. The review is divided into three main sections, and biomedical examples of the application of each presented approach are discussed. It is assumed that the undoubted advantages of ionic liquid-, microextraction- and capillary electrophoresis-based methods will speed up their use in the study of various clinically important analytes from different biological fluids and tissue samples.
Multiple reviews have been published on various aspects of carotenoid extraction. Nevertheless, n... more Multiple reviews have been published on various aspects of carotenoid extraction. Nevertheless, none of them focused on the discussion of recent green chemistry extraction protocols, especially for the carotenoids extraction from Daucus carota L. This group of bioactive compounds has been chosen for this review since most of the scientific papers proved their antioxidant properties relevant for inflammation, stress-related disorders, cancer, or neurological and neurodegenerative diseases, such as stroke and Alzheimer’s Disease. Besides, carrots constitute one of the most popular sources of carotenoids. In the presented review emphasis has been placed on the supercritical carbon dioxide and enzyme-assisted extraction techniques for the relevant tetraterpenoids. The detailed descriptions of these methods, as well as practical examples, are provided. In addition, the pros and cons of each method and comparison with the standard solvent extraction have been discussed.
A new approach for the sensitive, robust and rapid determination of idarubicin (IDA) in human pla... more A new approach for the sensitive, robust and rapid determination of idarubicin (IDA) in human plasma and urine samples based on liquid chromatography with fluorescence detection (LC-FL) was developed. Satisfactory chromatographic separation of the analyte after solid-phase extraction (SPE) was performed on a Discovery HS C18 analytical column using a mixture of acetonitrile and 0.1% formic acid in water as the mobile phase in isocratic mode. IDA and daunorubicin hydrochloride used as an internal standard (I.S.) were monitored at the excitation and emission wavelengths of 487 and 547 nm, respectively. The method was validated according to the FDA and ICH guidelines. The linearity was confirmed in the range of 0.1–50 ng/mL and 0.25–200 ng/mL, while the limit of detection (LOD) was 0.05 and 0.125 ng/mL in plasma and urine samples, respectively. The developed LC-FL method was successfully applied for drug determinations in human plasma and urine after oral administration of IDA at a dos...
Development and validation of a high-performance liquid chromatographic method with a fluorescence detector for the analysis of epirubicin in human urine and plasma, and its application in drug monitoring
Biogenic amines (BAs) are bioactive endogenous compounds which play a significant physiological r... more Biogenic amines (BAs) are bioactive endogenous compounds which play a significant physiological role in many cell processes like cell proliferation and differentiation, signal transduction and membrane stability. Likewise, they are important in the regulation of body temperature, the increase/decrease of blood pressure or intake of nutrition, as well as in the synthesis of nucleic acids and proteins, hormones and alkaloids. Additionally, it was confirmed that these compounds can be considered as useful biomarkers for the diagnosis, therapy and prognosis of several neuroendocrine and cardiovascular disorders, including neuroendocrine tumours (NET), schizophrenia and Parkinson’s Disease. Due to the fact that BAs are chemically unstable, light-sensitive and possess a high tendency for spontaneous oxidation and decomposition at high pH values, their determination is a real challenge. Moreover, their concentrations in biological matrices are extremely low. These issues make the measureme...
Practical Application of Biogenic Amine Profiles for the Diagnosis of Patients with Ischemic Stroke
Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association, 2018
Ischemic stroke (IS) is still one of the major issues in medicine. Still, early diagnosis and mis... more Ischemic stroke (IS) is still one of the major issues in medicine. Still, early diagnosis and misdiagnosis remain the main barriers for proper patient treatment and follow-up. Exploring new potential diagnostic biomarkers for IS is relevant to decrease patient morbidity and the occurrence of poststroke diseases. Biomedical analysis could bring new light to the background of IS and-in such a way-propose new bioanalytical tools for the early diagnosis, prognostication, and monitoring of IS. This research aimed to present a discussion on the employment of biogenic amines (BAs), as well as their precursory amino acids and main metabolites, as a new panel of biomarkers for IS. Preliminary patient data were presented and the patients were described with respect to their clinical history and examination records, as well as scientific data gained from the liquid extraction-capillary electrophoresis determination of BAs in the patients' urine samples. The results showed the potential of ...
International journal of molecular sciences, Jan 24, 2018
The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of var... more The determination of neurotransmitters (NTs) as relevant potential biomarkers in the study of various central nervous system (CNS) pathologies has been demonstrated. Knowing that NTs-related diseases mostly occupy individual regions of the nervous system, as observed, for instance, in neurodegenerative diseases (Alzheimer’s and Parkinson’s Diseases), the analysis of brain slices is preferred to whole-brain analysis. In this report, we present sample preparation approaches, such as solid-phase extraction, solid-phase microextraction, and dispersive liquid⁻liquid microextraction, and discuss the pitfalls and advantages of each extraction method. The ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate)-assisted solid-phase microextraction (IL-SPME) is found to be, in our research, the relevant step towards the simultaneous determination of six NTs, namely, dopamine (DA), adrenaline (A), noradrenaline (NA), serotonin (5-HT), l-tryptophan (l-Trp), l-tyrosine (l-Tyr) i...
Simultaneous electrokinetic and hydrodynamic injection and sequential stacking featuring sweeping for signal amplification following MEKC during the analysis of rapamycin (sirolimus) in serum samples
Electrophoresis, 2018
Simultaneous electrokinetic and hydrodynamic injection of rapamycin (sirolimus) with off-line and... more Simultaneous electrokinetic and hydrodynamic injection of rapamycin (sirolimus) with off-line and online sample preconcentration techniques and using MEKC has been studied. Compared to conventional hydrodynamic injection, a 168-fold improvement in the signal was obtained with a combination of simultaneous electrokinetic and hydrodynamic injectionand field enhanced sample injection in conjunction with a sweeping technique called sequential stacking featuring sweeping. However, the coupling of the developed electrophoretic method and solid-phase microextraction allowed the signal intensity to increase more than 231 times. In this approach, the injection of the sample at negative polarity (anode at the detector end) into the capillary and the MEKC separation was achieved within 5 min using an electrolyte (composed of 10 mM sodium tetraborate and 40 mM SDS) when ultraviolet (UV) detection was performed at 280 nm. Thus, by combining the application of the sequential stacking featuring sw...
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