ABSTRACT
BACKGROUND: The presence of calcium phosphate crystals such as basic calcium phosphate and calcium pyrophosphate dihydrate in intra-articular fluid is linked to a number of destructive arthropathies and detection of these deposits is often pivotal for early diagnosis and appropriate management of such disease. RESULTS: We describe the use of a calcium-sensitive dye, Fluo-4, to selectively label calcium-containing mineral deposits in synovial fluid, which can then be easily visualized using a standard fluorescence microscope. Furthermore, we have combined the fluorescent properties of the tagged crystals with flow cytometry as a fast and semi-quantitative method of detection. CONCLUSION: Dot-plots were used to quantify differences between various types of arthropathies and confirmed by visual observation of the crystals under a fluorescence microscope.
Subject(s)
Calcium Pyrophosphate/analysis , Microscopy, Fluorescence/methods , Synovial Fluid/chemistry , Aniline Compounds/chemistry , Arthritis, Rheumatoid/diagnosis , Calcium Oxalate/analysis , Crystallization , Flow Cytometry/methods , Gout/diagnosis , Humans , Osteoarthritis/diagnosis , Xanthenes/chemistryABSTRACT
An online SPE-LC method that can determine both anthracyclines and taxanes simultaneously in human serum samples is reported. The entire method of extraction, separation and UV detection was achieved online by column switching between an SPE column (Biotrap 500 (20 x 4 mm)) and an analytical column (Zorbax XDB C18, 150 x 4.6 mm, 5 microm) with a 23 min total cycle time. The method is linear (r(2)>0.998) over the range of 0.5-25 microg/mL. The analytes of interest are retained on the SPE column with good recovery (84-117%), while proteins and other serum components elute to waste. This online clean-up is much faster (150 s) and less manual than traditional off-line extraction methods. Using 0.1 mL spiked serum samples, the LOQ was 0.5 microg/mL. Intra- and inter-day precision were acceptable (< or = 15% RSD) at and above the LOQ. The method was applied to the analysis of serum samples from patients undergoing chemotherapy with these agents.
Subject(s)
Anthracyclines/blood , Chromatography, High Pressure Liquid/methods , Taxoids/blood , Anthracyclines/chemistry , Antineoplastic Agents/blood , Blood Proteins/chemistry , Calibration , Chemistry, Pharmaceutical/methods , Chromatography/methods , Daunorubicin/blood , Docetaxel , Doxorubicin/blood , Epirubicin/blood , Humans , Paclitaxel/blood , Sensitivity and Specificity , Taxoids/chemistryABSTRACT
The development of antibiotic resistance in bacteria has been attributed to the overuse of antimicrobials in human medicine. Another route by which humans are exposed to antibiotics is through the animal foods we eat. In modern agricultural practice, veterinary drugs are being used on a large scale, administered for treating infection or prophylactically to prevent infection. Hence, there is pressure on analytical scientists to detect and confirm the presence of antimicrobials in foods of animal origin. The aminoglycosides and macrolides are two families of antibiotics, each with important applications in veterinary medicine. These antibiotics are widely used in the treatment of bacterial disease, e.g., aminoglycosides for mastitis and macrolides for enteric infections. They have also been used as feed additives for growth promotion. As a result, legislation has been laid down by the European commission in which member states must meet strict criteria for monitoring residues (including antimicrobials). Testing for low levels of aminoglycosides and macrolides in foods is a priority and hence the development of fast, reliable, sensitive methods for their extraction and subsequent analysis is of great interest. This paper reviews analytical methods for both extracting and determining these classes of antibiotics in various food matrices focusing in particular on the last 10 years. Extraction and clean-up methods such as deproteinisation, and solid-phase extraction are described. Various screening methods are also covered including thin layer chromatography (TLC), enzyme immunoassay, capillary electrophoresis (CE) and microbiological assays. Finally, liquid chromatography (LC) methods are discussed which are combined with mass spectrometry (MS) when sensitivity requirements are stringent.
Subject(s)
Aminoglycosides/analysis , Anti-Bacterial Agents/analysis , Drug Residues/analysis , Food Analysis/methods , Food Contamination/analysis , Macrolides/analysis , Analytic Sample Preparation Methods/methods , Chromatography, Liquid/methods , Food Contamination/legislation & jurisprudenceABSTRACT
The surface of superparamagnetic magnetic beads was modified with bisphosphonates to selectively capture calcium phosphate crystals from complex biological fluids (i.e. synovial fluid).
