the beautiful hair, how to grind hair sample for detections

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  • 1. The Beautiful HairUseClick to edit Master subtitle styleof human hair sample for detectionsWISBIOMED, lab equipment & reagent

2. Human Hairmulti layers structure, constantly growsWISBIOMED, lab equipment & reagent 3. Hair growth Human hair grows constantly. Average 1-3cm/month Hair fiber can be grinded into powders for analysis 2003 Society of Hair Test suggested a set of guidelines for using human head hair as the sample for drug tests Sample collection Sample storage Sample pre cleaningWISBIOMED, lab equipment & reagent 4. Sample collection, storage The sample should be cut from the posterior vertex region of the head, as close as possible to the scalp, since this is the region of least variation in growth rate. If not, the source of the sampling should be described. In general, head hair is estimated to grow at approximately 1.0 cm per month. The sampling does not need to be performed by a physician The colour, length, body site and any obvious cosmetic treatment of the hair should be recorded Root (proximal) and tip (distal) sections of the hair should be clearly defined If segmental analysis is required, a lock of hair must be fixed before cutting Head hair is the preferred specimen. Alternative hair (e.g. pubic, axillary) can be collected if head hair is unavailable The sample and any aliquots or extracts must be handled and stored in a manner so as to minimize degradation, loss of analyte, or contamination from other sources. Dry hair should be stored in the dark at room temperature. There must be adequate sample to allow initial testing, followed by confirmatory or re-testing of the sample if necessary. A lock of hair, with the thickness of a pencil, or several locks with the thickness of a straw is recommended. In post-mortem cases, hair should be collected at the beginning of an autopsyWISBIOMED, lab equipment & reagent 5. Decontamination Areas of possible contamination must be considered before andduring the analysis. These may include, but are not limited to,external drug exposure and laboratory contaminationA simple use of cut-off levels is insufficient because externalcontamination can be at any level.In general, a decontamination strategy must include an initialorganic solvent, to remove oils, followed by aqueous washes.The washings should be stored for later analysis, if necessaryIn autopsy or exhumation cases, additional pre-treatment of thehair in the laboratory may be necessary, depending on the condition of the sampleWISBIOMED, lab equipment & reagent 6. Hair disintegration andextraction Different analytical procedures can produce differentquantitative results. Each laboratory has the choice ofdisintegrating the hair matrix before extraction, or ofextracting the drug directly from the solid hair after suitablepreparation Degradation compounds may be produced during the assay.In order to assess the degree of conversion, the laboratorymust include adequate controlsWISBIOMED, lab equipment & reagent 7. Tests: many tests can be done Opiates Cocaine Amphetamines CannabinoidsWISBIOMED, lab equipment & reagent 8. Use Precellys powderize hair sampleWISBIOMED, lab equipment & reagent 9. 2ML sample tube protocol Pre cut hair into 2cm long fragment Transfer hair samples into 2ML screw cap tubes, 2mg byweight Add metal grinding beads Precellys 24: 5000 rpm as a three cycle operation ofpulverizing for 30 s and suspending for 10 s When the hair sample pulverized, add appropriate liquid(depend on your next step of the assay) to recover the samplefrom grinding vial.WISBIOMED, lab equipment & reagent 10. 7ML sample tube Sample : around 150 mg of smooth or frizzy hair (cut