Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Biofluid”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed2002

Microfluidic chips for clinical and forensic analysis.

This review gives an overview of developments in the field of microchip analysis for clinical diagnostic and forensic applications. The approach chosen to review the literature is different from that in most microchip reviews to date, in that the information is presented in terms of analytes tested rather than microchip method. Analyte categories for which examples are presented include (i) drugs (quality control, seizures) and explosives residues, (ii) drugs and endogenous small molecules and ions in biofluids, (iii) proteins and peptides, and (iv) analysis of nucleic acids and oligonucleotides. Few cases of microchip analysis of physiological samples or other "real-world" matrices were found. However, many of the examples presented have potential application for these samples, especially with ongoing parallel developments involving integration of sample pretreatment onto chips and the use of fluid propulsion mechanisms other than electrokinetic pumping.

Antibodies↗
PubMed2006

High resolution 1H NMR investigations of the oxidative consumption of salivary biomolecules by ozone: relevance to the therapeutic applications of this agent in clinical dentistry.

High resolution proton (1H) nuclear magnetic resonance (NMR) spectroscopy was employed to simultaneously evaluate the oxidising actions of ozone (O3) towards a wide range of salivary biomolecules in view of its applications in dental practices, which may serve as a viable and convenient means for the treatment of dental caries. Treatment of supernatants derived from unstimulated human saliva specimens (n=12) with O3 (4.48 mmol) revealed that this reactive oxygen species gave rise to the oxidative consumption of pyruvate (generating acetate and CO2 as products), lactate (to pyruvate and sequentially acetate and CO2), carbohydrates in general (a process generating formate), methionine (giving rise to its corresponding sulphoxide), and urate (to allantoin). Further, minor O3-induced modifications included the oxidation of trimethylamine and 3-D-hydroxybutyrate, the fragmentation of salivary glycosaminoglycans to NMR-detectable saccharide fragments, and the conversion of polyunsaturated fatty acids to their ozonides. Moreover, evidence for the ability of O3 to induce the release of selected low-molecular-mass salivary biomolecules from macromolecular binding-sites was also obtained. Since many of the oxidation products detectable in O3-treated samples are identical to those arising from the attack of *OH radical on biofluid components, it appears that at least some of the modifications observed here are attributable to the latter oxidant (derived from O3*- generated from the single electron reduction of O3).

Carbohydrates↗
PubMed2006

Determination of the illicit drug gamma-hydroxybutyrate (GHB) in human saliva and beverages by 1H NMR analysis.

High resolution 1H NMR spectroscopy has been employed to investigate the detection and quantification of the illicit "date-rape" drug gamma-hydroxybutyrate (GHB) in both human saliva and a commonly-consumed low-alcohol beer product. Data acquired revealed that this multicomponent analytical technique provided unequivocal evidence for the detection of this agent by this technique in both of these matrices, i.e., all three of its resonances [those ascribable to the alpha-CH2 (t, delta=2.25 ppm), beta-CH2 (tt, delta=1.81 ppm) and gamma-CH2 (t, delta=3.61 ppm) group protons] were present in spectra acquired on human saliva, and two of these (the alpha- and beta-CH2 group signals) in the beverage product examined, the latter observation attributable to overlap of the gamma-CH2 1H resonance with those of carbohydrates. Since good linear calibration relationships between the intensities of each of the NMR-visible signals and added GHB concentration (the former normalised to that of an external 3-trimethylsilyl [2,2,3,3-2H4]- propionate standard present in a coaxial NMR tube insert) were observed, this illicit drug is also readily quantifiable in such multicomponent samples. Our data demonstrate the advantages offered by this technique when applied to the analysis of illicit drugs in multicomponent sample matrices such as human biofluids and beverage products.

Adult↗
PubMedDate not supplied

A liquid chromatographic method for the determination of fenoprofen in equine plasma and urine.

A high performance liquid chromatographic method to measure plasma and urine fenoprofen levels in equine biofluids is described. Liquid-liquid extraction with diethylether was used to isolate the drug from plasma and urine. The accuracy and reproducibility of the method were within acceptable limits over the concentration range 0-10 micrograms/mL and 0-20 micrograms/mL respectively from plasma and urine. Detection limits were 0.05 microgram/mL (2 mL plasma) and 0.2 microgram/mL (0.5 mL urine). This procedure was applied to ascertain the pharmacokinetics of a 3 g dose of fenoprofen calcium in a horse.

Animals↗
PubMedDate not supplied

Polymeric reagents for derivatizations in micellar electrokinetic chromatography.

A polymer immobilized o-nitrobenzophenone reagent was prepared for analysis of amine drugs in micellar electrokinetic chromatography (MEKC). A model compound, propylamine, was used to characterize the reagent's performance in MEKC. Derivatizations were performed on the CE instrument with reagent in the sample vial. The yielded derivative was directly sampled from the reaction mixture, and directly injected onto the MEKC system. The derivatization reagent was also applied to the derivatization of n-alkyl amine mixtures and amino acids. The method was validated for adamantanamine in urine and in plasma by single-blind spike analysis. Precisions and accuracies for all samples were less than 6.0% for urine samples and 10% for plasma samples. The procedure was a direct injection technique requiring minimal sample preparation for the analysis of drugs in biofluids.

Amantadine↗
PubMed2005

The expanding role of mass spectrometry in metabolite profiling and characterization.

Mass spectrometry has a strong history in drug-metabolite analysis and has recently emerged as the foremost technology in endogenous metabolite research. The advantages of mass spectrometry include a wide dynamic range, the ability to observe a diverse number of molecular species, and reproducible quantitative analysis. These attributes are important in addressing the issue of metabolite profiling, as the dynamic range easily exceeds nine orders of magnitude in biofluids, and the diversity of species ranges from simple amino acids to lipids to complex carbohydrates. The goals of the application of mass spectrometry range from basic biochemistry to clinical biomarker discovery with challenges in generating a comprehensive profile, data analysis, and structurally characterizing physiologically important metabolites. The precedent for this work has already been set in neonatal screening, as blood samples from millions of neonates are tested routinely by mass spectrometry as a diagnostic tool for inborn errors of metabolism. In this review, we will discuss the background from which contemporary metabolite research emerged, the techniques involved in this exciting area, and the current and future applications of this field.

Biomarkers↗
PubMed1991

In vitro hydrolysis of RR,SS-threo-methylphenidate by blood esterases--differential and enantioselective interspecies variability.

Enantioselective in vitro hydrolysis of methylphenidate (MPH) by the blood esterases of seven mammalian species is reported. The species included rats, rabbits, dogs, cattle, horses, monkeys, and humans. In vitro incubations up to 8 h were carried out in plasma, red blood cells, and whole blood of the various species. Enantioselective differences were evident among the different species on comparison of the data obtained from the three biological fluids. The esterases present in plasma appeared to show greater activity in the hydrolysis of MPH in all species where comparison with the other two biofluids was possible. Only in the case of humans did esterases present in plasma and red blood cells demonstrate opposite enantioselectivity in the hydrolysis of MPH. Thus after 8 h incubation, the RR-MPH/SS-MPH ratios in plasma and red blood cells were 0.31 and 1.16, respectively.

Animals↗
PubMed2005

Poly(dimethylsiloxane) thin films as biocompatible coatings for microfluidic devices: cell culture and flow studies with glial cells.

Oxygen plasma treatment of poly(dimethylsiloxane) (PDMS) thin films produced a hydrophilic surface that was biocompatible and resistant to biofouling in microfluidic studies. Thin film coatings of PDMS were previously developed to provide protection for semiconductor-based microoptical devices from rapid degradation by biofluids. However, the hydrophobic surface of native PDMS induced rapid clogging of microfluidic channels with glial cells. To evaluate the various issues of surface hydrophobicity and chemistry on material biocompatibility, we tested both native and oxidized PDMS (ox-PDMS) coatings as well as bare silicon and hydrophobic alkane and hydrophilic oligoethylene glycol silane monolayer coated under both cell culture and microfluidic studies. For the culture studies, the observed trend was that the hydrophilic surfaces supported cell adhesion and growth, whereas the hydrophobic ones were inhibitive. However, for the fluidic studies, a glass-silicon microfluidic device coated with the hydrophilic ox-PDMS had an unperturbed flow rate over 14 min of operation, whereas the uncoated device suffered a loss in rate of 12%, and the native PDMS coating showed a loss of nearly 40%. Possible protein modification of the surfaces from the culture medium also were examined with adsorbed films of albumin, collagen, and fibrinogen to evaluate their effect on cell adhesion.

Animals↗
PubMed2004

Applications of proteomic methodologies to human pregnancy research: a growing gestation approaching delivery?

Maternal and perinatal morbidity and mortality rates are significantly higher in pregnancies complicated by preterm labor, pre-eclampsia and fetal growth restriction. Decades of research have not translated into a clear understanding of the underlying pathophysiologies or effective identification of women who are at high risk of developing these complications. Often the severity of these diseases does not correlate with the clinical symptoms, and current diagnostic methods are unable to accurately predict the conditions prior to clinical presentation. Though several potential markers have been proposed for each of these disorders, to date none have proven clinical utility. Emerging proteomic technology is only beginning to be employed in pregnancy research. A comprehensive analysis of gestational tissues can be expected to contribute to the elucidation of the complex molecular mechanisms of pregnancy and related complications. Comparison of the expression profiles of normal and pathogenic tissues and biofluids may also highlight novel candidate marker proteins that have so far remained undetected. More interestingly, rapidly evolving technologies using sophisticated bioinformatic tools are demonstrating their potential in disease diagnostics by using overall protein profiles to detect diseases. The clinical significance of these methodological advances is enormous. Early diagnosis together with improved understanding of underlying molecular mechanisms can enhance outcomes and increase effective management and therapeutic options.

Biomarkers↗
PubMed2006

Shotgun proteomic analysis of human-induced sputum.

Induced sputum is a readily accessible biological fluid whose composition may alter as a consequence of disease. To date, however, the proteins that routinely populate this biofluid are largely unknown, in part due to the technical difficulties in processing such mucin-rich samples. To provide a catalogue of sputum proteins, we have surveyed the proteome of human-induced sputum (sputome). A combination of 2-D gel analysis and GeLC-MS/MS allowed a total of 191 human proteins to be confidently assigned. In addition to the expected components, several hitherto unreported proteins were found to be present, including three members of the annexin family, kallikreins 1 and 11, and peroxiredoxins 1, 2 and 5. Other sets of proteins identified included four proteins previously annotated as hypothetical or conserved hypothetical. Taken together, these data represent the first extensive survey of the proteome of induced sputum and provide a platform for future identification of biomarkers of lung disease.

Chromatography, Liquid↗
PubMed2006

Strategies for plasma proteomic profiling of cancers.

Despite a voluminous literature on potential protein biomarkers and a compelling need for diagnostic tests based on biomarkers to detect cancers at much earlier, more treatable stages, progress has been limited. New methods and new instruments for analysis of differences in gene expression, gene methylation, and proteomics are being employed to try to accelerate the discovery phase. Given the heterogeneity of tumor mechanisms and the limitations of analytical methods, it is likely that a variety of strategies will be needed and will be complementary. That is the basis of this review of proteomic approaches. This article adopts a systems biology view, starting with mRNA transcripts in tumors and cultured tumor cells to detect mRNA overexpression, some of which will be correlated with protein overexpression. Some of those proteins may be secreted or released into proximal biofluids and plasma. Detection of low-abundance tumor proteins in the complex and dynamic mixture that is plasma requires combinations of increasingly powerful technologies. The biological amplification of protein signals through the immune system offers autoantibodies as potential biomarkers. Higher abundance proteins, including acute-phase reactants, may have practical value, especially if the proteins are modified as part of the cancer processes. Low molecular weight proteins, fragments, and peptides may offer complementary biomarkers. Promising biomarker candidates must be confirmed in independent studies. Then they must be submitted to higher-throughput methods practical for large-scale validation studies and, hopefully, for clinical and epidemiological applications. Standardized operating procedures for specimen handling, design and use of various reference standards, care to avoid bias and confounding, and guidelines for reporting findings and contributing datasets should enhance the prospects for predictive proteomic profiling of people at risk for cancers.

Biomarkers, Tumor↗
PubMed2006

Ultra-fast mass fingerprinting by high-affinity capture of peptides and proteins on derivatized poly(glycidyl methacrylate/divinylbenzene) for the analysis of serum and cell lysates.

The development of support materials in mass fingerprinting is an important task required for diagnostic markers in conjunction with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The material-based approach, which we introduced as material-enhanced laser desorption/ionization (MELDI), focuses not only on different functionalities, but also emphasizes the morphology, i.e. porosity or particle size of the carrier material. As a result, it provides a quick and sensitive platform for effective binding of peptides and proteins out of different biofluids, e.g. serum, spinal fluid, urine or cell lysates, and to subsequently analyze them with MALDI-TOF MS. This approach includes a built-in desalting step for serum protein profiling and is sensitive enough to detect proteins and peptides down to 100 fmol/microL. Here we co-polymerized glycidyl methacrylate (GMA) with divinylbenzene (DVB) using thermal polymerization to yield a GMA/DVB polymer for further modifications. Different affinities have been created, such as immobilized metal ion affinity (IDA-Cu2+), reversed-phase (RP) and anion-exchanger (AX) chromatography. The diverse derivatizations and the dispersity of the particles created by different chemical synthetic approaches were confirmed by characteristic infrared (IR) peaks. The polymerization carried out by non-stirring yielded an average pore radius of 6.1 microm (macro-pores) that enhanced the binding capacity enormously by offering enlarged surface areas. Moreover, atomic absorption spectrometry (AAS) provided the metal content loaded on iminodiacetic acid (IDA) in the case of poly(GMA/DVB)-IDA-Cu2+. To summarize, the optimized MELDI approach is sensitive in its performance, extremely fast and can be adapted to robotic systems for routine analysis, allowing sample preparation in less than 5 min in contrast to the conventional surface-enhanced laser desorption/ionization (SELDI) methods.

Blood Proteins↗
PubMed2026

Multidimensional Protein Corona Analysis Toward Predictive Nano-Bio Interface Design.

Nanoparticles entering biological fluids are rapidly coated by proteins and other biomolecules, converting their synthetic surfaces into biologically active nano-bio interfaces. These coronas regulate colloidal stability, immune recognition, cellular uptake, biodistribution, pharmacokinetics, cargo delivery, and toxicity. Yet a protein list obtained by mass spectrometry captures only part of this interface. Corona identity and function are also shaped by protein organization, binding stability, exchange dynamics, conformational changes, and molecular accessibility. Here, we discuss recent progress in protein corona isolation and analysis from a question-oriented analytical perspective, with emphasis on how centrifugation, magnetic recovery, affinity- or chemistry-enabled capture, chromatography, filtration, and field-flow fractionation (FFF) influence the fidelity, integrity, and comparability of recovered coronas. We then examine how proteomic profiling can be integrated with binding measurements, interfacial structural analysis and functional validation to distinguish descriptive corona signatures from biologically meaningful mechanisms. We further consider how biofluid composition, disease state, tissue interfaces and cellular environments remodel corona identity, presentation, and bioactivity. Finally, we argue that standardized reporting, computational modeling, and AI-enabled approaches are essential for converting protein corona datasets into reproducible and predictive knowledge that can guide the design of drug delivery systems and precision nanomedicines.

Protein Corona↗
PubMed1994

Extraction of magnesium from biological fluids using 8-hydroxyquinoline and cation-exchange chromatography for isotopic enrichment analysis using thermal ionization mass spectrometry.

The use of 8-hydroxyquinoline to precipitate magnesium was evaluated as a method for preparing biological samples for isotopic enrichment analysis using thermal ionization mass spectrometry (TIMS). Standard curves in matrices of water, serum, and urine were prepared using varying amounts of 25Mg. The 25Mg/24Mg isotope ratio was measured by TIMS using a silica gel/phosphoric acid technique. Although the total Mg recovered by precipitation from the matrices varied considerably and was dependent on matrix, recovery was sufficient for isotopic enrichment analysis. Urine samples required cation-exchange chromatography (Bio-Rex AG 50W-X8 filter membrane, Bio-Rad Laboratories) prior to precipitation to remove contaminants which interfered with the thermal ionization process. The observed versus expected 25Mg/24Mg enrichments were evaluated using linear regression analysis: water, y = 0.016 + 1.022x; serum, y = 0.5 + 1.097x; urine, y = -0.004 + 0.943x. This method has proven useful for the isolation of magnesium from the biofluids tested.

Body Fluids↗
PubMed1994

High-field deuterium nuclear magnetic resonance spectroscopic monitoring of the pharmacokinetics of selectively deuterated benzoic acid in man.

The stable isotope tracer technique using 13C labeling of substrates followed by NMR spectroscopy of biofluids has been widely used in metabolic investigations, whereas the use of 2H labeling and 2H NMR spectroscopy has been extremely limited. The applicability of the high-field 2H NMR spectroscopy (14.1 T, 92 MHz 2H frequency) in a simple pharmacokinetic problem has now been investigated using selectively deuterated benzoic acid (BA) as a model. [7-13C,2,6-2H2]BA was synthesized for use as a tracer to compare the efficiency and sensitivity of 2H and 13C labeling. The urinary excretion of [7-13C,2,6-2H2]hippuric acid (HA) formed from orally administered [7-13C,2,6-2H2]BA (250 mg) was followed by 92-MHz 2H and 150-MHz 13C NMR spectroscopy (only 10 min accumulation time) following concentration of urine by a factor of 10, using a standard for quantitation. The heights of resonances for 13C7 and 2H2,6 were used to calculate the [7-13C,2,6-2H2]HA concentration. The lower limit of detection using this 2H NMR approach was approximately 60 nmol/ml and was found to be comparable with that of the 13C NMR approach where the quaternary carbon (C7) was labeled. The administered [7-13C,2,6-2H2]BA was found to be quantitatively biotransformed to HA and excreted in urine within 4 h by both NMR approaches. The 2H NMR approach using a high-field NMR spectrometer is potentially useful and practical for pharmacokinetic research on small molecules whose 2H resonances are relatively sharp since the procedures are very simple and convenient.

Benzoates↗
PubMed2001

Detection and quantification of beta-2-microglobulin using mass spectrometric immunoassay.

The use of mass spectrometric immunoassay (MSIA) in analyzing beta-2-microglobulin (beta(2)m) present in human biological fluids (tears, saliva, plasma, and urine) is described. Pipettor tips containing porous affinity frits, derivatized with polyclonal anti-beta(2)m immunoglobulin, were manufactured and used to selectively isolate and concentrate beta(2)m from the biofluids, after which matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to detect beta(2)m unambiguously at its characteristic molecular mass. The affinity tips were found rapid to use, requiring approximately 15 min per analysis, and exhibited low nonspecific binding properties that yielded essentially interference-free analyses. The beta(2)m MSIA was made quantitative by inclusion of an internal standard into the analysis for signal normalization. The resulting assay had a Linear dynamic range (R(2) = 0.983) covering a beta(2)m concentration range of 0.010-1.0 mg/L with a standard error of approximately 5%. In application, urine samples from healthy individuals were screened and compared with sample from an individual suffering from renal infection. Results indicated an approximately 30-fold increase in beta(2)m levels in samples taken from the infected individual. During the screening, MSIA was able to distinguish between wild-type and glycosylated forms of beta(2)m, which made possible the accurate quantification of wild-type beta(2)m without interference from glycosylated versions of the protein. These results demonstrate a new approach to the rapid and accurate detection/quantification of beta(2)m present in biological fluids.

Adult↗
PubMed2007

Nuclear magnetic resonance metabonomics: methods for drug discovery and development.

Nuclear magnetic resonance (NMR)-based metabonomics is gaining popularity in drug discovery and development and in academia in a variety of settings, ranging from toxicology, preclinical, and clinical approaches to nutrition research, studies on microorganisms, and research on plants. This chapter focuses on the basic steps in a metabonomics study and emphasizes experience and lessons learned in our lab where we focused on metabonomic analyses of plant extracts, cell lines, and a variety of animal tissues and biofluids. We emphasize that a comprehensive and suitable study design is pivotal for a correct biological interpretation of the results, as well as highly controlled experimental conditions. Sample preparation and NMR protocols are detailed for a wide range of sample types. We discuss alternative data processing strategies and considerations for a general data analysis approach, paying particular attention to the statistical interpretation and validation of the results while also highlighting approaches to avoid possible pitfalls resulting from systematic and random errors. A tutorial written for the R statistical package and other small utilities are available from the authors upon request.

Animals↗
PubMed1978

Isolation of drugs from autopsy material by XAD-2 adsorption-elution technique. A routine procedure.

The method of adsorption of drugs on Amberlite XAD-2 resin, followed by differential elution was under study during 1 1/2 year of routine use. The method allows a separation of acidic and basic drugs and--due to acid hydrolysis step before adsorption--assures better recovery of conjugated and protein-bound drugs. The amounts of various drugs, found in autopsy cases by the XAD-2 method were usually higher than those found by solvent extraction. The method applied requires 20 g of sample (biofluid or tissue) for general toxicological analysis.

Adsorption↗