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Potassium hydroxide: an alternative reagent to perform the modified apt test.
Henry Chicaiza1, Karl Hellstrand1, Trudy Lerer2
1Connecticut Children's Medical Center, Hartford, CT; University of Connecticut School of Medicine, Farmington, CT.
The Journal of Pediatrics
|July 1, 2014
Summary
Potassium hydroxide (KOH) effectively differentiates fresh fetal and adult blood stains, similar to sodium hydroxide, in a modified Apt test. This finding suggests KOH
Area of Science:
- Forensic Science
- Biochemistry
Background:
- The Apt test is a presumptive test for blood.
- Distinguishing fetal from adult blood is crucial in forensic investigations.
Purpose of the Study:
- To evaluate the efficacy of potassium hydroxide (KOH) in a modified Apt test.
- To compare KOH performance against sodium hydroxide (NaOH) as a positive control.
- To assess the utility of KOH for bedside blood stain analysis.
Main Methods:
- A modified Apt test was performed.
- Potassium hydroxide (KOH) was used as the primary reagent.
- Sodium hydroxide (NaOH) served as the positive control.
- Experimental conditions were varied.
- Performance was assessed on fresh and dried blood stains on cloth.
Main Results:
- Potassium hydroxide (KOH) successfully differentiated fresh fetal and adult blood stains.
- KOH performance was comparable to sodium hydroxide (NaOH).
- Neither KOH nor NaOH could differentiate dried blood stains.
Conclusions:
- Potassium hydroxide (KOH) is a viable reagent for the modified Apt test.
- The test's effectiveness is limited to fresh blood stains.
- KOH offers potential for point-of-care or bedside forensic blood analysis.
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