Forensic Biology by Richard LiBiological CharacteristicsSlide 3SpermatozoaAcid PhosphataseProstate-Specific AntigenSeminal Vesicle Specific AntigenLighting TechniquesColorimetric AssayFluororimetric AssayConfirmatory TestsChapter 8: Identification of SemenTypical ejaculation2-5 ml of semenSeminal fluid▪Seminal vesicle fluid- 60% of ejaculate▪Prostatic fluid secretions- 30% of ejaculate▪Acid Phospahatase (AP) & Prostate Specific Antigen (PSA)▪Epididymis and bulbourethral glands- each 5%Sperm cells- SpermatozoaForensic Biology by Richard Li 2Vasectomy- block spermatozoaStill produces ejaculate with seminal vesicle fluid and prostatic fluidOligospermia- low sperm countAspermia- no spermForensic Biology by Richard Li 3Three distinct regions:HeadMiddle PieceTailForensic Biology by Richard Li 4Optimal activity in acidic pH environmentPresent in lysosomesProstate AP Half-life at 37 degrees C: 6 monthsForensic Biology by Richard Li 5Major protein in seminal fluidAlso detected in urine, fecal matter, sweat, milkHalf-life of dried stain: 3 yearsForensic Biology by Richard Li 6SemenogelinsI & IIHigher concentration in seminal fluid than PSANot found in urine, milk, sweat Forensic Biology by Richard Li 7Locating dried stainsUV lightArgon laserAlternate light source (ALS)▪450-495 nmForensic Biology by Richard Li 8AP catalyzes the removal of the phosphate group from a substratePositive= purple colorForensic Biology by Richard Li 9More sensitive than colorimetricAP catalyzes the removal of the phosphate residue on the substrate 4-methylumbelliferone phosphate which generates fluorescence under UV light Forensic Biology by Richard Li 10Microscopic examinationChristmas Tree StainLaser capture microdissectionIdentification of prostate-specific antigenRadial immunodiffusionRocket immunoelectrophoresisCIEELISAImunnochromatographic assaysForensic Biology by Richard Li 11Most
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