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CHEMICAL ENHANCEMENT OF FINGERPRINTS IN BLOOD AN EVALUATION OF METHODS

CHEMICAL ENHANCEMENT OF FINGERPRINTS IN BLOOD AN EVALUATION OF METHODS. DR. J.D. DEHAAN J.D. CLARK T.F. SPEAR S.S. BARNEY. BEFORE. AFTER. PHOTOGRAPHY WAS THE ONLY METHOD TO ENHANCE BLOODY IMPRESSIONS. BEFORE. AFTER.

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CHEMICAL ENHANCEMENT OF FINGERPRINTS IN BLOOD AN EVALUATION OF METHODS

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  1. CHEMICAL ENHANCEMENT OF FINGERPRINTS IN BLOODAN EVALUATION OF METHODS DR. J.D. DEHAAN J.D. CLARK T.F. SPEAR S.S. BARNEY

  2. BEFORE AFTER PHOTOGRAPHY WAS THE ONLY METHOD TO ENHANCE BLOODY IMPRESSIONS

  3. BEFORE AFTER AMIDO BLACK WAS USED TO CHEMICALLY ENHANCE THE BLOODY FINGERPRINT

  4. BEFORE AFTER AND THE BLOODY SHOE PRINT

  5. COLOR CHANGE AMIDO BLACK NINHYDRIN LEUCO CRYSTAL VIOLET FLUORESCENCE FLUORESCIN MERBROMIN DFO (Initial tests confirmed published reports that the absorption of the blood quenched the fluorescence of DFO. No further study was done with DFO) REAGENTS WERE EVALUATED THAT COULD CHANGE THE COLOR OR FLUORESCE THE BLOOD

  6. REAGENTS WERE EVALUATED FOR THE FOLLOWING • SENSITIVITY • EFFECTS OF THE SUBSTRATE • EFFECTS OF TIME • FLUORESCING CAPABILITIES • EDGE DETAIL AFTER PROCESSING • IMPACT ON DNA ANALYSIS

  7. SENSITIVITY WAS MEASURED BY SEQUENTIAL TOUCHES OF FINGERS MOISTENED WITH HUMAN BLOOD

  8. ALSO BY SERIAL DILUTION

  9. AMIDO BLACK LEUCO CRYSTAL VIOLET DUE TO THE TIME REQUIRED FOR NINHYDRIN TO REACT, IT WAS NOT CONDUCIVE FOR USE IN THE FIELD AND STUDY WAS LIMITED TO ONLY SERIAL DILUTION TARGETS USED FOR COLOR

  10. POROUS TARGETS WERE IMPACTED BY AMIDO BLACK WHILE LEUCO CRYSTAL VIOLET WAS NOT • AMIDO BLACKLEUCO CRYSTAL VIOLET

  11. OXIDATION CAN BE REDUCED BY RINSING WITH DISTILLED WATER AFTER REAGENT APPLICATION LEUCO CRYSTAL VIOLET OXIDIZES BY LIGHT AND TIME FORMING BACKGROUND COLOR

  12. SERIAL DILUTION FLUORESCENT CAPABILITY TESTS DISCOVERED THAT LEUCO CRYSTAL VIOLET FLUORESCED AT 532nm

  13. NO EDGE DETAIL EVEN WITH FINE MISTING THE THICKENER USED IN FLUORESCIN IMPACTED EXTRACTING DNA. THE THICKENER WAS REMOVED FROM THE FORMULA FOR THIS TEST.

  14. THE SAME OXIDATION OCCURES WITH MERBROMIN. MINIMIZE OXIDATION WITH A DISTILLED WATER RINSE MERBROMIN HELD THE EDGE DETAIL WELL EVEN WITH HEAVY APPLICATION

  15. BEFORE AFTER LEUCO CRYSTAL VIOLET IS VERY EFFECTIVE ON SHOE PRINTS

  16. LEUCO CRYSTAL VIOLET MERBROMIN FLUORESCING IMPRESSIONS

  17. IMPACT ON DNA ANALYSIS 14 PCR MARKERS WERE SUCCESSFULLY TYPED WITH THE 6 TESTED REAGENTS

  18. SAFETYSr. Industrial Hygienist Rod Oswalt of the Calif. Criminalistics Institute Prepared A Hazard Assessment On Merbromin and Leuco Crystal Violet (LCV)The Hazards Of Mercury Is Well Known. Due to Mercury Being the Primary Reagent in Merbromin, It’s Use Should Be Limited To a Laboratory Vent Hood.The Published Articles Listed LCV As Relatively Safe With Moderate Caution.The Three Main Exposure Pathways Of Inhalation, Skin Absorption and Ingestion Are Viable Routes By The Application Methods. “LCV Is An Analogue Of The Aniline Compounds And Benzidine-BasedDyes, And The Body Will Readily Absorb LCV. Further, Many Of The Benzidine-Based Dyes Are Metabolized By The Human Body Into Benzidine, Which Is Known To Cause Cancer. It Is Unclear Based Upon Available Information, Whether LCV/CV is Metabolized Via That Pathway.”

  19. POROUS LEUCO CRYSTAL VIOLET (No background staining) NON-POROUS AMIDO BLACK (10 Times more sensitive than LCV) LEUCO CRYSTAL VIOLET (Hemoglobin Specific) CONCLUSIONSLIGHT COLOR TARGETS

  20. POROUS MERBROMIN (Fluoresces with many wave lengths) NON-POROUS MERBROMIN (Fluoresces with many wave lengths) CONCLUSIONSDARK COLOR TARGETS

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