Blood sampling systems

Sample vials can be made of various materials, depending on the supplier of the system for obtaining the sample. This can lead to problems if, for example, they have to be made of glass or other special materials to prevent loss of a particular analyte and they are not availkable from the manufacturer. Unfortunately, the various blood sampling systems are usually incompatible, so that the special vials are effectively non-interchangeable. 

Postal deliveries of blood sampling systems must not include the injection needle. 

Han SY, Chin Y-W, Choi YH (2013) A new approach for pharmacokinetic studies of natural products measurement of isoliquiritigenin levels in mice plasma, urine and feces using modified automated dosing/blood sampling system. Biomed Chromatogr 27 741-749... 

Pneumatic Pipelines. Pneumatic pipe systems are used to move blood samples, medicine, and suppHes between buildings in hospital complexes cash and receipts in drive-up banks parts and materials in factories refuse from apartment complexes and grain, cement, and many other materials. Most of these are small diameter and usually short however, a 17-km, 1220-mm dia pneumatic pipeline has been used to transport rock in the former Soviet Union since 1981, and a 3.2-km, 1000-mm dia line has moved limestone from the mine to a cement plant in Japan since 1983 (22). 

The uptake of TRA into cervical tissue was determined by measuring tissue radioactivity following insertion of the collagen sponge cervical cap containing tritium-labeled TRA. The TRA concentrations peaked at 4 hr and then diminished rapidly by 24 hr. Since measurements of blood samples revealed that no systemic absorption had occurred, high local concentrations over an extended period of time may be possible without systemic side effects. 

HIV phenotype A type of resistance testing for human immunodeficiency virus (HIV) in which a patient s blood sample is obtained, and the patient s HIV genes that encode for reverse transcriptase and protease are removed and placed in an HIV viral vector. This viral vector is replicated in a cell culture system with varying concentrations of antiretrovirals. A drug concentration-viral inhibition curve is developed and the concentration needed to inhibit 50% of the patient s virus is reported. This is used to predict resistance versus susceptibility. 

Figure 8.6 Positive ion LD TOF mass spectra of P. falciparum parasite sample (upper trace), and a control (uninfected blood) sample (lower trace). Protocol D is used for sample preparation. Both samples—in vitro cultured P. falciparum parasites in whole blood, and the whole blood control—are diluted to 5% hematocrit (10-fold) in PBS buffer. In the infected sample the estimated number of deposited parasites per sample well is approximately 100. A commercial LD TOF system is used, and both spectra are normalized to the same (40 mV) detector response value. Each trace represents the average of one hundred single laser shot spectra obtained from linear scanning of an individual well (no data smoothing). The characteristic fingerprint ions of detected heme in the upper trace are denoted.

The feasibility of an optical fiber system was demonstrated for the differential absorption analysis of the car pollutant nitrogen dioxide. It absorbs in the visible and can be "sensed" using an Ar-ion laser27. The yellow metabolite bilirubin has been monitored in blood via fiber optic spectrometry in serum28. The tip of a fiber optic cable was inserted into a injection needle so to reach the blood sample, and absorbance (and later fluorescence) was acquired of a sample contained in the cavity at the tip of the fiber or needle. 

M. Weiss, A. Dullenkopf, and U. Moehrlen, Evaluation of an improved blood-conserving POCT sampling system. Clin. Biochem. 37, 977-984 (2004). 

T.K. Lim, H. Ohta, and T. Matsunaga, Microfabricated on-chip-type electrochemical flow immunoassay system for the detection of histamine released in whole blood samples. Anal. Chem. 75, 3316-3321 (2003). 

Headspace analysis involves examination of the vapours derived from a sample by warming in a pressurized partially filled and sealed container. After equilibration under controlled conditions, the proportions of volatile sample components in the vapours of the headspace are representative of those in the bulk sample. The system, which is usually automated to ensure satisfactory reproducibility, consists of a thermostatically heated compartment in which batches of samples can be equilibrated, and a means of introducing small volumes of the headspace vapours under positive pressure into the carrier-gas stream for injection into the chromatograph (Figure 4.25). The technique is particularly useful for samples that are mixtures of volatile and non-volatile components such as residual monomers in polymers, flavours and perfumes, and solvents or alcohol in blood samples. Sensitivity can be improved by combining headspace analysis with thermal desorption whereby the sample vapours are first passed through an adsorption tube to pre-concentrate them prior to analysis. 

Blank, calibrator, control, and patient whole-blood samples (50 /iL) were transferred into 1.5 mL conical test tubes, mixed with 100 /xL of the IS, vortexed for 10 sec, and centrifuged at 13,000 g for 5 min. Twenty-five microliters of supernatant were injected onto a Cohesive Technologies Cyclone polymeric turbulent flow column (50 x 1 mm, 50 /flushed with a mixture of methanol and water (10 90 v/v) at a flow of 5 mL/min. Column switching from the TFC to HPLC systems was via a Cohesive Technologies system. The analytical column was a Phenomenex Phenyl-Hexyl-RP (50 x 2.1 mm, 5 /.mi). The mobile phase consisted of methanol and ammonium acetate buffer (97 3 v/v). The buffer was 10mM ammonium acetate containing 0.1% v/v acetic acid. The flow rate was 0.6 mL/min. 

Selecting a subset of animals or test systems from a study to make some measurement (which either destroys or stresses the measured system, or is expensive) at an interval during a study. This may include such cases as doing interim necropsies in a chronic study or collecting and analyzing blood samples from some animals during a subchronic study. 

Consider the analysis of a blood sample for alcohol content (imagine that a police officer suspects a motorist to be intoxicated). The problem here is not sampling different locations within a system, but rather a time factor. The blood must be sampled within a particular time frame in order to demonstrate intoxication at the time the motorist was stopped. 

Figure 6.3 Diagrammatic representation of the dry reagent strips known as reagent carriers, which are used in the Boehringer Reflotron System for the chemical analysis of blood samples. Red blood cells are removed in the separating layer and the plasma passing into the glass fibre transport layer is analysed. The magnetic code carries information about the analytical procedure.

An example of the possibilities for plastics to respond to a specific problem is the replacement of almost 100% of the stoppers, capsules, joints and other closure systems used for pharmaceutical products. The replacement of glass is the most-significant opportunity for the development of thermoplastics but new possibilities could appear in medical self-care systems and blood sample tubes. A 50-70% increase in the use of plastics should come from existing mass-produced and low-cost products. Let us quote, for example ... 

Two weeks after the booster, the mice are sacrificed by exposing them to CO gas, and a blood sample is taken from all mice by tail artery puncture for measurement of the systemic antibody response. 

Chinese hamsters exposed to ozone at 0.2 ppm for 5 h had an increased number of chromosomal breaks in their circulating lymphocytes. Blood samples for study were obtained immediately after exposure and 6 and 15.5 days later. The highest break frequency was observed after the longest delay. The authors compared the effects of X irradiation and ozone singly and combined, in their system. The combined effects were less than additive this suggested some protective mechanism, perhaps analogous to that observed by Hattori et al When the authors extrapolated their data to acceptable industrial-hygiene exposures to ozone and radiation, ozone was found to be much more likely than X irradiation to produce chromosomal breaks in such exposures. 

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