Development of D-π-A organic dyes for discriminating HSA from BSA and study on dye-HSA interaction

HSA (human serum albumin), a most abundant protein in blood serum, plays a key role in maintaining human health. Abnormal HSA level is correlated with many diseases, and thus has been used as an essential biomarker for therapeutic monitoring and biomedical diagnosis. Development of small-molecule fluorescent probes allowing the selective and sensitive recognition of HSA in in vitro and in vivo is of fundamental importance in basic biological research as well as medical diagnosis. Herein, we reported a series of new synthesized fluorescent dyes containing D-π-A constitution, which exhibited different optical properties in solution and solid state. Among them, dye M-H-SO3 with a hydrophilic sulfonate group at electron-acceptor part displayed selectivity for discrimination of HSA from BSA and other enzymes. Upon binding of dye M-H-SO3 with HSA, a significant fluorescence enhancement with a turn-on ratio about 96-fold was triggered. The detection limit was estimated to be ∼ 40 nM. Studies on the interaction mechanism revealed that dye M-H-SO3 could bind to site III of HSA with a 1:1 binding stoichiometry. Furthermore, dye M-H-SO3 has been applied to determine HSA in real urine samples with good recoveries, which provided a useful method for HSA analysis in biological fluids.

Spectrophotometric resolution for quantitative analysis of aspirin and rivaroxaban combination therapy in biological fluids using simple and eco-friendly procedure

Patients diagnosed with symptomatic peripheral artery disease (PAD) in the lower extremities have a higher likelihood of suffering from major vascular events. Recently, FDA has approved the combination therapy of aspirin (ASP) and rivaroxaban (ROX) to reduce acute limb ischemia and other comorbidities in (PAD) patients. Zero order and ratio absorption spectra were employed in three simple and accurate spectrophotometric techniques (dual wavelength (DW), ratio difference (RD) and derivative ratio (1DD) for concurrent detection and quantification of ASP and ROX in their pure forms, lab synthetic mixtures and in biological fluid. Our approach involves careful parameter optimization, including solvent selection, sample volumes, and instrumental settings, to reduce the analysis environmental impact. The acquired recovery percentages of accuracy were within 98-102% for pure active pharmaceutical ingredients and 90-110% for pharmaceutical formulations and biological determinations. A comprehensive assessment was done to compare the three methods regarding their ease of use, linearity, sensitivity, conditions, and limitations. The specificity of the proposed methods was evaluated by analyzing the lab synthetic mixtures. The suggested spectrophotometric methods were validated in compliance with ICH guidelines to confirm the validity claims. Also, statistical analysis was done to compare the outcomes obtained from the suggested methods with those obtained from the official ones and they agreed with null hypothesis regarding accuracy and precision. Furthermore, a comprehensive assessment of the environmental sustainability of the developed method was carried out using the Analytical Greenness Calculator, AGREE algorithm. The selected drugs can be efficiently, safely and economically analyzed by the suggested methods in pharmaceutical and biological matrices with no pretreatment or preliminary separation steps and thereby increasing their greenness level.

Lipid nanoparticles for targeted delivery of anticancer therapeutics: Recent advances in development of siRNA and lipoprotein-mimicking nanocarriers

The limitations inherent in conventional cancer treatment methods have stimulated recent efforts towards the design of safe nanomedicines with high efficacy for combating cancer through various promising approaches. A plethora of nanoparticles has been introduced in the development of cancer nanomedicines. Among them, different lipid nanoparticles are attractive for use due to numerous advantages and unique opportunities, including biocompatibility and targeted drug delivery. However, a comprehensive understanding of nano-bio interactions is imperative to facilitate the translation of recent advancements in the development of cancer nanomedicines into clinical practice. In this contribution, we focus on lipoprotein-mimicking nanoparticles, which possess unique features and compositions facilitating drug transport through receptor binding mechanisms. Additionally, we describe potential applications of siRNA lipid nanoparticles in the future design of anticancer nanomedicines. Thus, this review highlights recent progress, challenges, and opportunities of lipid-based lipoprotein-mimicking nanoparticles and siRNA nanocarriers designed for the targeted delivery of anticancer therapeutic agents.

Label-free detection of vitamin B by two-step enhanced Raman technique using dynamic borohydride-reduced silver nanoparticles

A creatively designed novel two-step enhancement technique is presented in which B vitamin molecules are dynamically adsorbed onto the surface of silver nanoparticles by sodium borohydride, followed by local plasmon resonance in the presence of cations (calcium ions), ultimately achieving synergistic chemical and physical enhancement on the same molecule and constructing a "surface hot spots" two-step enhancement platform for vitamin detection. The Raman signal of the promoted vitamin molecule is enhanced by nine orders of magnitude. In a subsequent study it was observed that the vitamin B2 molecules were in a near-vertical image on the surface of the silver nanoparticles, which may also contribute to the Raman signal enhancement. Combined with deep learning techniques, the method has been successfully applied to the detection of B vitamins in body fluids. As an accurate, rapid, reproducible, non-invasive, and versatile assay platform, it holds great promise for the intelligent identification of trace B molecules in food, pharmaceuticals, and the human body.

Solid phase extraction as sample pretreatment method for top-down quantitative analysis of low molecular weight proteins from biological samples using liquid chromatography - triple quadrupole mass spectrometry

Targeting and quantifying intact proteins from biological samples is still a very challenging research area. Several crucial steps exist in the analytical workflow, including development of a reliable sample preparation method. Here, we developed and applied for the first time a non-immunoaffinity sample preparation method based on a generally widely available micro-elution solid phase extraction (μSPE) strategy for the extraction of multiple lower molecular weight intact proteins (<30 kDa) from various biological matrices. Omission of a time-consuming drying and reconstitution step after extraction resulted in a more simple and rapid sample preparation procedure. A model set of eleven intact proteins (molecular weights: 5.5-29 kDa; isoelectric points: 4.5-11.3) were analyzed in multiple biological fluids using reversed-phase liquid chromatography with a triple quadrupole mass spectrometer operated in multiple reaction monitoring mode. Various sample pre-treatment reagents, sorbent types, and washing and elution solvents were experimentally tested and optimized to obtain the μSPE clean-up condition for a broad mixture of intact proteins having variable physicochemical properties. 1% trifluoroacetic acid and 0.2% Triton 100-X were selected as suitable sample pre-treatment reagents for releasing protein-protein interactions in human serum/plasma and human urine, respectively. Hydrophilic lipophilic balanced μSPE sorbent was selected as a high performing stationary phase. Addition of 1% trifluoroacetic acid to all washing and elution solutions showed the most beneficial effect for the extraction recovery of the proteins. Under the optimized conditions, reproducible extraction recoveries >65% for all targeted proteins (up to 30 kDa) in human urine and >50% for most of the proteins in serum/plasma were achieved. The selected conditions were applied also for the analysis of clinical serum and urine samples to demonstrate the feasibility of the developed method to target intact proteins directly by more affordable μSPE sample preparation and triple quadrupole mass spectrometry, which could be beneficial in many application fields.

Potential protein markers in children with Autistic Spectrum Disorder (ASD) revealed by salivary proteomics

The lack of specific pharmacological therapy for Autistic Spectrum Disorder (ASD) and its clinical heterogeneity demand efforts directed toward the identification of biomarkers to aid in diagnosis. Proteomics offers a new perspective for studying the altered proteins associated with autism spectrum disorders (ASD) and we have saliva as an easy-to-collect biological fluid with important biomolecules for investigating biomarkers in various diseases. In this sense, saliva could be used to identify potential biomarkers of ASD. In the current work, saliva samples were collected from children with different degrees of ASD and healthy children and proteomics approaches were applied to generate data on differentially expressed proteins between groups which will serve as a basis for future validation studies as protein markers. Data are available via ProteomeXchange with identifier PXD030065. As results, 132 proteins were present in 80% of the saliva pools of all analyzed groups. Twenty-five proteins were identified as overexpressed in the group of severe and mild/moderate ASD carriers, among which, eight were identified as potential biomarkers for ASD.

Smartphone-assisted electrochemical sensor for reliable detection of tyrosine in serum

Point-of-care devices have attracted a huge interest by the scientific community because of the valuable potentiality for rapid diagnosis and precision medicine through cost-effective and easy-to-use devices for on-site measurement by unskilled personnel. Herein, we reported a smartphone-assisted electrochemical device consisted of a screen-printed electrode modified with carbon black nanomaterial and a commercially available smartphone potentiostat i.e. EmStat3 Blue, for sensitive detection of tyrosine. Once optimized the conditions, tyrosine was detected in standard solutions by square wave voltammetry, achieving a linear range comprised between 30 and 500 μM, with a detection limit equal to 4.4 μM. To detect tyrosine in serum, the interference of another amino acid i.e. tryptophan was hindered using a sample treatment with an extraction cartridge. The agreement of results analyzing serum samples with HPLC reference method and with the developed smart sensing system demonstrated the suitability of this smartphone-assisted sensing tool for cost-effective and rapid analyses of tyrosine in serum samples.

Novel lanthanum vanadate-based nanocomposite for simultaneously electrochemical detection of dopamine and uric acid in fetal bovine serum

The abnormal levels of two biological molecules, dopamine (DA) and Uric acid (UA), in human body are symptoms of diseases such as Parkinson's disease and arrhythmia. A novel lanthanum vanadate and multi-walled carbon nanotubes (LaV-MWCNTs) composite modified glassy carbon electrode (GCE) was developed and utilized as an efficient electrochemical sensor for the simultaneous detection of DA and UA. LaV-MWCNTs composite was successfully fabricated by a facile ultrasonic self-assembly method and identified by means of a series of successive measurements including XPS, XRD, FT-IR and FE-SEM. The LaV-MWCNTs modified GCE shows the concentration linear ranges of DA and UA are 2-100 μΜ using DPV. The limits of detection (LODs; signal-to-noise ratio of 3, S/N = 3) of the LaV-MWCNTs modified GCE sensor for DA and UA were calculated to be 0.046 μM and 0.025 μM, respectively. The feasibility of using the LaV-MWCNTs modified GCE sensor to detect DA and UA in a typical biological fluid, fetal bovine serum, was also evaluated by the standard addition method.

NMR characterization of H2O2 hydrogen exchange

Quantification of H2O2 concentration in aqueous solutions is of interest in many fields. It usually is based on indirect methods that rely on oxidation reactions that turn on/off fluorescent probes. Such methods can suffer from reaction incompleteness and interfering chemical species. We describe optimization of NMR detection that enables direct quantification of H2O2 down to the nanomolar range. Taking advantage of fast hydrogen exchange (HX) between H2O2 and water permits the use of very short interscan delays, greatly increasing sensitivity. The specific acid-, base- and water-catalyzed HX rates at 2 °C were measured to be 2.1 × 107, 6.1 × 109, and 1.4 × 10-1 M-1s-1, respectively, which result in a minimum HX rate at pH 6.2. Furthermore, the exchange is accelerated by general acid/base catalysis. MES and phosphate buffers catalyze HX strongest in their unprotonated forms. For imidazole, only the unprotonated form catalyzes HX, which contrasts with acetic acid where only the protonated state catalyzes exchange. Inorganic salts such as sodium chloride and azide have negligible effect on HX. We present optimal conditions for accurate measurement of H2O2 concentrations as low as 40 nM in aqueous samples in a few hours.

Circulating miRNA repertoire as a biomarker of metabolic and reproductive states in rainbow trout

Background

Circulating miRNAs (c-miRNAs) are found in most, if not all, biological fluids and are becoming well-established non-invasive biomarkers of many human pathologies. However, their features in non-pathological contexts and whether their expression profiles reflect normal life history events have received little attention, especially in non-mammalian species. The aim of the present study was to investigate the potential of c-miRNAs to serve as biomarkers of reproductive and metabolic states in fish.

Results

The blood plasma was sampled throughout the reproductive cycle of female rainbow trout subjected to two different feeding regimes that triggered contrasting metabolic states. In addition, ovarian fluid was sampled at ovulation, and all samples were subjected to small RNA-seq analysis, leading to the establishment of a comprehensive miRNA repertoire (i.e., miRNAome) and enabling subsequent comparative analyses to a panel of RNA-seq libraries from a wide variety of tissues and organs. We showed that biological fluid miRNAomes are complex and encompass a high proportion of the overall rainbow trout miRNAome. While sharing a high proportion of common miRNAs, the blood plasma and ovarian fluid miRNAomes exhibited strong fluid-specific signatures. We further revealed that the blood plasma miRNAome significantly changed depending on metabolic and reproductive states. We subsequently identified three evolutionarily conserved muscle-specific miRNAs or myomiRs (miR-1-1/2-3p, miR-133a-1/2-3p, and miR-206-3p) that accumulated in the blood plasma in response to high feeding rates, making these myomiRs strong candidate biomarkers of active myogenesis. We also identified miR-202-5p as a candidate biomarker for reproductive success that could be used to predict ovulation and/or egg quality.

Conclusions

Together, these promising results reveal the high potential of c-miRNAs, including evolutionarily conserved myomiRs, as physiologically relevant biomarker candidates and pave the way for the use of c-miRNAs for non-invasive phenotyping in various fish species.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-021-01163-5.

Exosomes in chronic respiratory diseases

Exosomes are nano-sized vesicles released by almost all cell types, with a central role as mediators of intercellular communication. In addition to physiological conditions, these extracellular vesicles seem to play a pivotal role in inflammatory processes. This assumption offers the opportunity to study exosomes as promising biomarkers and therapeutic tools for chronic respiratory disorders. Indeed, although it is well-known that at the basis of conditions like asthma, chronic obstructive pulmonary disease, alpha-1 antitrypsin deficiency and idiopathic pulmonary fibrosis there is a dysregulated inflammatory process, an unequivocal correlation between different phenotypes and their pathophysiological mechanisms has not been established yet. In this review, we report and discuss some of the most significant studies on exosomes from body fluids of subjects affected by airway diseases. Furthermore, the most widespread techniques for exosome isolation and characterization are described. Further studies are needed to answer the unresolved questions about the functional link between exosomes and chronic respiratory diseases.

Antifouling lipid membrane coupled with silver nanoparticles for electrochemical detection of nucleic acids in biological fluids

Electrochemical method capable of detecting specific nucleic acids in complex fluid will undoubtedly advance the diagnosis of many kinds of diseases. Herein, by coupling lipid membrane with silver nanoparticles (AgNPs), we develop a new electrochemical method for sensitive and reliable detection of nucleic acids in biological fluids. The advantages of lipid membrane especially its excellent antifouling ability is employed to enhance the applicability of the method in complex environment; while the significant solid-state Ag/AgCl response of AgNPs is used to ensure the detection sensitivity of the method. The core of this method's workflow is the target-induced Y-shape structure formation, which results in the recruitment of AgNPs to the electrode surface, producing considerable electrochemical responses used for target nucleic acid detection. Taking highly upregulated in liver cancer (HULC), a liver cancer-related long non-coding RNA as a model target, the method exhibits high sensitivity, specificity, and reproducibility with a detection limit of 0.42 fM. Moreover, the method displays desirable usability in biological fluids such as serum, which will be of great potential in clinical diagnosis.

Resonance Rayleigh scattering technique-using erythrosine B, as novel spectrofluorimetric method for determination of anticancer agent nilotinib: Application for capsules and human plasma

A exceedingly touchy resonance Rayleigh scattering (RRS) strategy for the assurance of nilotinib (NILO) was introduced. In the pH 3.4 acetate buffer solution, NILO reacted with erythrosine B to produce an ion-association complex, which increased the RRS intensity of the studied system. The enhanced RRS intensity (ΔI) was linearly proportional to the concentration of NILO, the linear range of the method was 0.1-1.0 µg/mL and the detection limit (DL) was 0.025 µg/mL. In like manner, this test was connected to distinguish the concentration of NILO in capsules and human plasma with palatable comes about.

Seasonal stability of SARS-CoV-2 in biological fluids

Transmission of SARS-CoV-2 occurs by close contact with infected persons through droplets, the inhalation of infectious aerosols and the exposure to contaminated surface. Previously, we determined the virus stability on different types of surfaces under indoor and seasonal climatic conditions. SARS-CoV-2 survived the longest on surfaces under winter conditions, followed by spring/fall and summer conditions, suggesting the seasonal pattern of stability on surfaces. However, under natural conditions, the virus is secreted in various biological fluids from infected humans. In this respect, it remains unclear how long the virus survives in various types of biological fluids. This study explored the SARS-CoV-2 stability in human biological fluids under different environmental conditions and estimated the half-life. The virus was stable for up to 21 days in nasal mucus, sputum, saliva, tear, urine, blood, and semen; it remained infectious significantly longer under winter and spring/fall conditions than under summer conditions. In contrast, the virus was only stable up to 24 hours in feces and breast milk. These findings demonstrate the potential risk of infectious biological fluids in SARS-CoV-2 transmission and have implications for its seasonality.

Fast fabric phase sorptive extraction of selected β-blockers from human serum and urine followed by UHPLC-ESI-MS/MS analysis

A fast fabric phase sorptive extraction method is presented herein for the rapid isolation of selected beta-blocker drugs from human serum and urine. Among many high efficiency sol-gel sorbent coated FPSE membranes, sol-gel CW20 M coated FPSE membrane was identified as the best FPSE membrane for the target beta-blocker drugs possessing logP values ranging from 0.1 (highly polar) to 3.1 (moderately polar). Due to the engineered affinity towards the analytes via complementary intermolecular interactions and high mass transfer rate of the analytes from the bulk sample solution to the FPSE membrane, the extraction is accomplished in relatively short time (15 min) while its high permeability permits the direct extraction of biological samples without any other pretreatment. The advantages of the fabricated extraction membrane were exploited for the determination of six beta-blockers (namely atenolol, nadolol, metoprolol, oxprenolol, labetalol and propranolol) in biological matrices in combination with UHPLC-ESI-MS/MS. Important parameters including extraction time, sample volume, sorbent size, elution solvent, etc. affecting the performance of the extraction were systematically investigated. The linearity of the method was evaluated in the range of 50-5000 ng mL^-1 by constructing weighted (1/X) matrix-matched calibration curves. The intra-day and inter-day trueness were ranged between - 17.2 to 13.3% and - 10.8 to 12.6%, respectively. The intra-day and inter-day precision were less than 11.5 and 14.5 %, respectively. The proposed analytical scheme was successfully applied to the determination of the target drugs in human serum and urine.

Analysis of daunorubicin and its metabolite daunorubicinol in plasma and urine with application in the evaluation of total, renal and metabolic formation clearances in patients with acute myeloid leukemia

This report presents improved analysis methods of daunorubicin (DAUN) and its metabolite daunorubicinol (DAUNOL) in small volumes of plasma, as total and unbound concentrations, as well as in urine. This study also presents the pharmacokinetics of DAUN and DAUNOL in patients (n = 12) diagnosed with acute myeloid leukemia treated with intravenous DAUN (60 mg/m²/day, for three days). Serial blood and urine samples were collected up to 144 h after the beginning of the first infusion. The analytical methods presented no significant matrix effect. The linear ranges were 0.1-1000 ng/mL in plasma, 0.05-40 ng/mL in ultrafiltrate and 0.5-3000 ng/ml in urine. The precision and accuracy presented coefficients of variation and standard errors lower than 15 % in the three matrices. The methods allowed for the quantification of samples up to 144 h after the beginning of the first infusion. Unbound fractions for DAUN and DAUNOL were 23.91 % (17.33-32.99) and 29.23 % (25.84-33.07), respectively. The fraction recovered in urine was 4.40 % (3.87-5.03) for DAUN and 7.91 % (6.86-9.19) for DAUNOL. Total 292.96 L/h (261.74-327.90), renal 13.01 L/h (11.44-14.88), and hepatic 280.26 L/h (248.40-317.91) clearances of DAUN, as well as the DAUNOL formation clearance 23.41 L/h (19.09-28.97), were evaluated.

One-pot micellar augmented native fluorescence for facile fluorimetric assay of dapoxetine hydrochloride in biological plasma and tablets

One of the medical problems is premature ejaculation which characterized by quick ejaculation and reaching orgasm rapidly. Dapoxetine was accepted as off-label antidepressant used in the treatment of premature ejaculation, so hereby we provide an innovative, non-extractive, environmentally safe protocol for the assay of dapoxetine in biological plasma and tablet. The principle of the assay is simple and only based on native fluorescence which was enhanced by micelle. Parameters influencing the method were optimized and measurements were accomplished at emission wavelength of 338 nm after excitation at 294 nm. The fluorescence-concentration plot was rectilinear over the range of 0.1-4 μg/mL. Directives of ICH guideline were the rules which followed to ensure the validity of the work. Eventually, the procedure was utilized in the dosage form assay and extended to include biological plasma analyses, with good percentage recuperation.

5'-Hydroxymethyl fluorescein: A colorimetric chemosensor for naked-eye sensing of cyanide ion in a biological fluid

A two-step synthetic method to prepare a highly sensitive and selective chemosensor 5'-hydroxymethyl fluorescein (5'-HMF) is described herein. This sensor was explored as a colorimetric sensor for naked-eye detection of cyanide ion in the biological fluid as well as in organic and aqueous media. The addition of cyanide ion to 5'-HMF resulted in a rapid change in color in aqueous medium from light green to dark fluorescent green, and in acetonitrile from light pink to purple. A significant bathochromic shift in the absorption spectra enables cyanide ion to be detected by naked eyes in water and acetonitrile without any interference of the competing anions such as, AcO^-, F^- and SCN^- in aqueous solution. Using the ¹HNMR titration experiments and Job's plot from absorbance spectroscopy, the interaction of CN^- ion with 5'-HMF has been investigated and binding stoichiometry was found to be 1:2 (5'-HMF to CN^-). The limit of detection (LOD) of the sensor for CN^- was 3.68 μM in water with a linearity (R² = 0.9923) in the range of 0.50 to 30.0 μM concentration assuming 1:2 (5'-HMF to CN^-) binding stoichiometry. In addition, the sensor 5'-HMF sensed the CN^- ion in human saliva with the LOD as 7.0 μM in aq. medium.

In-situ fabrication of zeolite imidazole framework@hydroxyapatite composite for dispersive solid-phase extraction of benzodiazepines and their determination with high-performance liquid chromatography-VWD detection

A novel zeolite imidazole framework@hydroxyapatite composite (ZIF-8@HAP) was constructed via in-situ growth and developed for efficient dispersive solid-phase extraction (DSPE) of three benzodiazepines from urine samples. The prepared composite was characterized by scanning electron microscopy, energy-dispersive spectrometer, Fourier-transform infrared spectrometry, X-ray diffractometry, zeta potential analyzer, and nitrogen adsorption-desorption experiment. Characterization results showed typical dodecahedron ZIF-8 crystals that were uniformly located on the surface of rod-like HAP. The combination of ZIF-8 and HAP made the surface area significantly enhanced from 4.68 to 205.44 m² g^-1. Compared with a commercial C₁₈ adsorbent, ZIF-8@HAP exhibited superior removal performance for interfering components from urine and offered better extraction properties for the analytes. The prepared ZIF-8@HAP was applied as an adsorbent in DSPE, and the main experimental parameters, including pH and ionic strength of solution, adsorbent amount, adsorption time, elution solvent, and volume, were investigated. Under optimal conditions, the adsorption for 250 ng mL^-1 of each analyte in 4 mL of urine was accomplished within 2 min using 60 mg of adsorbent. The method of ZIF-8@HAP-based DSPE followed by high-performance liquid chromatography gave enhancement factors of 13.3-15.3, linear ranges of 2.5-500 ng mL^-1, and limits of detection (S/N = 3) of 0.7-1.4 ng mL^-1. The relative recoveries at three spiked levels ranged from 88.7 - 102% with intra-day and inter-day precisions from 3.0 - 10.3% and 2.3 - 12.3%, respectively. These results indicated that the proposed strategy had promising applicability for convenient, rapid, and efficient determination of benzodiazepines in urine samples.Graphical abstract In-situ fabrication of ZIF-8@HAP composite for dispersive solid-phase extraction of benzodiazepines in urine samples.

A rapid FTIR spectroscopic assay for quantitative determination of Memantine hydrochloride and Amisulpride in human plasma and pharmaceutical formulations

A selective, new, rapid and nondestructive Fourier transform Infrared spectroscopic assay has been developed for simultaneous determination of Memantine hydrochloride and Amisulpride in human plasma and their pharmaceutical formulations without interference from common dugs excipients. A binary mixture of ME and nonselective β-blocker namely; carvidalol has been determined the solid-state by FTIR spectroscopy for the first time. The linear range had been extent from 1.0 to 8.0 and 1.0 to 10.0 μg/mg, for ME and AMS respectively. The detection limits were 0.29 and 0.23 μg/mg while quantitation limits were 0.90 and 0.71 μg/mg for ME and AMS respectively. The developed assay has been validated according to ICH & USP recommendations and successfully applied for quantitative determination of selected drugs in biological fluid.

A new spectrofluorimetric assay for quantification of Amisulpride and Memantine hydrochloride in real human plasma sample and pharmaceutical formulations via Hantzsch reaction

A new, selective and accurate spectrofluorimetric assay has been described for detection of Amisulpride and Memantine hydrochloride in pharmaceutical formulations and real plasma samples. The described assay depends on the reaction between the primary amino group of the selected drugs with acetyl acetone & formaldehyde in an acetate buffer of pH4.8. The derivatized product showed yellow fluorescence at λ_ex=418nm and λ_em=484.5nm. The calibration graph was linear in the range of 0.05-0.5 and 0.2-1μgmL^-1 for AMS and ME, orderly. The limits of detection were 0.0085 and 0.0153μgmL^-1, and the limits of quantitation were 0.026 and 0.0464μgmL^-1 for AMS and ME respectively. Validation of the described assay was in consonance with ICH guideline. Due to the sensitivity of the prescribed assay, it permits the determination of selected medications in biological sample quantitatively.

Cellulose cone tip as a sorbent material for multiphase electrical field-assisted extraction of cocaine from saliva and determination by LC-MS/MS

A porous and hydrophilic sorbent material was used in an extraction system, assisted by electric fields, for the extraction of cocaine in saliva and subsequent determination by ultra-high-performance liquid chromatography associated with sequential triple quadrupole mass spectrometry (UHPLC-MS/MS). The cellulose-based material was characterized by scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. The time and voltage variables applied in the extraction process were investigated through a Doehlert experimental design, and with the best conditions found (35min and 300 V) some validation parameters were evaluated. The established working range was 1-100 μg L^-1 (R² > 0.99), and the detection and quantification limits determined were 0.3 and 0.8 μg L^-1, respectively. Recoveries from 80 to 115% and coefficient of variation ≤15 and 16% for intra-day and inter-day assays, respectively, were obtained for sample concentrations of LOQ, 5, 25, and 75 μg L^-1, indicating satisfactory accuracy and precision for the proposed method. In addition, the method presented no matrix effect, and the extraction efficiency was between 56 and 70%. The results showed that the material used has adequate physicochemical characteristics and can be applied as a sorbent and electrolyte support in multiphase extractions using electric fields.

Rapid detection of pathogenic virus genome sequence from throat and nasal swab samples using an exhaustive gene amplification method

Rapid identification of pathogenic agents is important in response to the emergence of biocrime and bioterrorism, to facilitate appropriate confinement and treatment. As the rapid determination system of viral genome sequences (RDV method) using exhaustive gene amplification is useful for rapid identification, we examined whether this method could be applied to forensic samples. To detect pathogenic virus in a cat with suspected viral infections, fluid swab samples were applied to the RDV method. The following steps were performed: viral propagation, extraction of the viral genome, amplification of the first library, fragmentation of the library, amplification of the second library using non-specific primer sets, and direct sequencing of the amplicon. To confirm the viruses detected by this method, we performed conventional PCR using virus-specific primers. We detected pathogenic virus genome sequences from the swab samples and confirmed infection with these viruses. In addition, we directly detected a viral genome sequence from the nasal swab sample without the viral propagation step. The RDV method is infrequently used in forensic analysis. This method is practicable with equipment existing in a normal laboratory and is useful for rapid detection and identification of pathogenic viruses in forensic samples. This method would also be applicable to the detection of bacteria and fungi.

A new sensitive approach for spectrofluorimetric assay of Milnacipran and Amisulpride in real plasma and pharmaceutical preparations via complexation with Eosin Y dye

An accurate, economic, rapid, reliable spectrofluorimetric assay was developing for the assay of definite anti-depressant drugs namely Amisulpride and Milnacipran hydrochloride, in those pharmaceutical preparation and biological fluid. The suggested method was established on the detection of quenching process resulting from the action of AMS and MCN to the native fluorescent EosinY. A binary complex between selected medications and Eosin Y was established in acetate buffer (0.2 M) at pH 3.3 & 4.0 for AMS and MCN respectively. The relative fluorescence capacity was determined at λex = 301.8 nm and λem = 542.7 nm. The calibration graphs had been linear through extent from 0.02 to 0.3 and 0.1-1 μg mL^-1, to both dugs respectively. Detection limits have been 0.0047 & 0.0188 μg mL^-1 while quantitation limits have been 0.0141 & 0.0569 μg mL^-1 to AMS & MCN respectively. Developed assay has been validated in agreement with ICH recommendations. Due to high sensitivity of the described assay, it allows the quantitation of anti-depressant drugs through biological fluid.

Protein corona variation in nanoparticles revisited: A dynamic grouping strategy

Bio-nano interface investigation models are mainly based on the type of proteins present on corona, bio-nano interaction responses and the evaluation of final outcomes. Due to the extensive diversity in correlative models for investigation of nanoparticles biological responses, a comprehensive model considering different aspects of bio-nano interface from nanoparticles properties to protein corona fingerprints appeared to be essential and cannot be ignored. In order to minimize divergence in studies in the era of bio-nano interface and protein corona with following therapeutic implications, a useful investigation model on the basis of RADAR concept is suggested. The contents of RADAR concept consist of five modules: 1- Reshape of our strategy for synthesis of nanoparticles (NPs), 2- Application of NPs selected based on human fluid, 3- Delivery strategy of NPs selected based on target tissue, 4- Analysis of proteins present on corona using correct procedures and 5- Risk assessment and risk reduction upon the collection and analysis of results to increase drug delivery efficiency and drug efficacy. RADAR grouping strategy for revisiting protein corona phenomenon as a key of success will be discussed with respect to the current state of knowledge.

Comparing human peritoneal fluid and phosphate-buffered saline for drug delivery: do we need bio-relevant media?

An understanding of biological fluids at the site of administration is important to predict the fate of drug delivery systems in vivo. Little is known about peritoneal fluid; therefore, we have investigated this biological fluid and compared it to phosphate-buffered saline, a synthetic media commonly used for in vitro evaluation of intraperitoneal drug delivery systems. Human peritoneal fluid samples were analysed for electrolyte, protein and lipid levels. In addition, physicochemical properties were measured alongside rheological parameters. Significant inter-patient variations were observed with regard to pH (p < 0.001), buffer capacity (p < 0.05), osmolality (p < 0.001) and surface tension (p < 0.05). All the investigated physicochemical properties of peritoneal fluid differed from phosphate-buffered saline (p < 0.001). Rheological examination of peritoneal fluid demonstrated non-Newtonian shear thinning behaviour and predominantly exhibited the characteristics of an entangled network. Inter-patient and inter-day variability in the viscosity of peritoneal fluid was observed. The solubility of the local anaesthetic lidocaine in peritoneal fluid was significantly higher (p < 0.05) when compared to phosphate-buffered saline. Interestingly, the dissolution rate of lidocaine was not significantly different between the synthetic and biological media. Importantly, and with relevance to intraperitoneal drug delivery systems, the sustained release of lidocaine from a thermosensitive gel formulation occurred at a significantly faster rate into peritoneal fluid. Collectively, these data demonstrate the variation between commonly used synthetic media and human peritoneal fluid. The differences in drug release rates observed illustrate the need for bio-relevant media, which ultimately would improve in vitro-in vivo correlation.

Assessment of Blood Contamination in Biological Fluids Using MALDI-TOF MS

Biological fluid sample collection often includes the risk of blood contamination that may alter the proteomic profile of biological fluid. In proteomics studies, exclusion of contaminated samples is usually based on visual inspection and counting of red blood cells in the sample; analysis of specific blood derived proteins is less used. To fill the gap, we developed a fast and sensitive method for ascertainment of blood contamination in crude biological fluids, based on specific blood-derived protein, hemoglobin detection by MALDI-TOF MS. The MALDI-TOF MS based method allows detection of trace hemoglobin with the detection limit of 0.12 nM. UV-spectrometry, which was used as reference method, was found to be less sensitive. The main advantages of the presented method are that it is fast, effective, sensitive, requires very small sample amount and can be applied for detection of blood contamination in various biological fluids collected for proteomics studies. Method applicability was tested on human cerebrospinal and follicular fluid, which proteomes generally do not contain hemoglobin, however, which possess high risk for blood contamination. Present method successfully detected the blood contamination in 12 % of cerebrospinal fluid and 24 % of follicular fluid samples. High percentage of contaminated samples accentuates the need for initial inspection of proteomic samples to avoid incorrect results from blood proteome overlap.

Direct Analysis of Amphetamine Stimulants in a Whole Urine Sample by Atmospheric Solids Analysis Probe Tandem Mass Spectrometry

Amphetamine-type stimulants (ATS) are among illicit stimulant drugs that are most often used worldwide. A major challenge is to develop a fast and efficient methodology involving minimal sample preparation to analyze ATS in biological fluids. In this study, a urine pool solution containing amphetamine, methamphetamine, ephedrine, sibutramine, and fenfluramine at concentrations ranging from 0.5 pg/mL to 100 ng/mL was prepared and analyzed by atmospheric solids analysis probe tandem mass spectrometry (ASAP-MS/MS) and multiple reaction monitoring (MRM). A urine sample and saliva collected from a volunteer contributor (V1) were also analyzed. The limit of detection of the tested compounds ranged between 0.002 and 0.4 ng/mL in urine samples; the signal-to-noise ratio was 5. These results demonstrated that the ASAP-MS/MS methodology is applicable for the fast detection of ATS in urine samples with great sensitivity and specificity, without the need for cleanup, preconcentration, or chromatographic separation. Thus ASAP-MS/MS could potentially be used in clinical and forensic toxicology applications.

Rapid determination of furosemide in drug and blood plasma of wrestlers by a carboxyl-MWCNT sensor

A novel method is developed for the quantification of furosemide in biological fluids. The method is based on the electro-reduction of Zn(II)-furosemide complex at carboxyl-MWCNT modified glassy carbon electrode. It is shown that, in Britton-Robinson buffer (pH5.7) the reduction peak of Zn(II)-furosemide complex formed at -1.0 V (versus, Ag/AgCl). The increment of current signal obtained from the reduction peak current of the Zn(II)-furosemide complex was rectilinear with furosemide concentration in the range of 0.03 to 140.0 μg ml(-1), with a detection limit of 0.007 μg ml(-1). The drug recovery ranged between 97.8% and 100.8% and the mean drug recovery was 98.89%. The accuracies (relative error% and RSD%) were less than 15% and are acceptable according to the US FDA guideline for bioanalytical method validation. The sensor was used for quantification of furosemide in drug and biological fluid samples. The data of drug analysis were compared with the standard method.

Organic solvent-free air-assisted liquid-liquid microextraction for optimized extraction of illegal azo-based dyes and their main metabolite from spices, cosmetics and human bio-fluid samples in one step

Air-assisted liquid-liquid microextraction (AALLME) has unique capabilities to develop as an organic solvent-free and one-step microextraction method, applying ionic-liquids as extraction solvent and avoiding centrifugation step. Herein, a novel and simple eco-friendly method, termed one-step air-assisted liquid-liquid microextraction (OS-AALLME), was developed to extract some illegal azo-based dyes (including Sudan I to IV, and Orange G) from food and cosmetic products. A series of experiments were investigated to achieve the most favorable conditions (including extraction solvent: 77μL of 1-Hexyl-3-methylimidazolium hexafluorophosphate; sample pH 6.3, without salt addition; and extraction cycles: 25 during 100s of sonication) using a central composite design strategy. Under these conditions, limits of detection, linear dynamic ranges, enrichment factors and consumptive indices were in the range of 3.9-84.8ngmL(-1), 0.013-3.1μgmL(-1), 33-39, and 0.13-0.15, respectively. The results showed that -as well as its simplicity, fastness, and use of no hazardous disperser and extraction solvents- OS-AALLME is an enough sensitive and efficient method for the extraction of these dyes from complex matrices. After optimization and validation, OS-AALLME was applied to estimate the concentration of 1-amino-2-naphthol in human bio-fluids as a main reductive metabolite of selected dyes. Levels of 1-amino-2-naphthol in plasma and urinary excretion suggested that this compound may be used as a new potential biomarker of these dyes in human body.

Surface tension in human pathophysiology and its application as a medical diagnostic tool

Introduction: Pathological features of disease appear to be quite different. Despite this diversity, the common feature of various disorders underlies physicochemical and biochemical factors such as surface tension. Human biological fluids comprise various proteins and phospholipids which are capable of adsorption at fluid interfaces and play a vital role in the physiological function of human organs. Surface tension of body fluids correlates directly to the development of pathological states.

Methods: In this review, the variety of human diseases mediated by the surface tension changes of biological phenomena and the failure of biological fluids to remain in their native state are discussed.

Results: Dynamic surface tension measurements of human biological fluids depend on various parameters such as sex, age and changes during pregnancy or certain disease. It is expected that studies of surface tension behavior of human biological fluids will provide additional information and might become useful in medical practice. Theoretical background on surface tension measurement and surface tension values of reference fluids obtained from healthy and sick patients are depicted.

Conclusion: It is well accepted that no single biomarker will be effective in clinical diagnosis. The surface tension measurement combined with routine lab tests may be a novel non-invasive method which can not only facilitate the discovery of diagnostic models for various diseases and its severity, but also be a useful tool for monitoring treatment efficacy. We therefore expect that studies of surface tension behavior of human biological fluids will provide additional useful information in medical practice.

Application of LC-MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

Liquid chromatography tandem mass chromatography (LC-MS/MS) is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC-MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase) as well as different acquisition modes (SIM, MRM) for quantitative analysis of glucocorticoids and stimulants. This review is not meant to be exhaustive but rather to provide a general overview for detection and confirmation of target drugs using LC-MS/MS and thus useful in the doping analysis, toxicological studies as well as in pharmaceutical analysis.