Elemental composition of platelets. Part I. Sampling and sample preparation of platelets for trace-element analysis

Area of Science:

• Biochemistry
• Hematology
• Analytical Chemistry

Background:

• Platelet sampling for trace-element analysis faces challenges including purity, viability, trapped plasma, and contamination.
• Accurate elemental analysis requires overcoming these sampling hurdles to ensure reliable results.

Purpose of the Study:

• To develop and validate a robust method for isolating pure, viable platelets for trace-element analysis.
• To establish optimal conditions for differential centrifugation and contamination control during platelet collection.

Main Methods:

• Utilized a blood-cell separator for initial platelet isolation, followed by differential centrifugation in natural plasma.
• Employed pyrimidopyrimidine RA233 as a viability stabilizer and 131I-labeled human serum albumin to quantify trapped plasma.
• Controlled contamination using five-times-distilled water and analyzed three blood fractions; elemental analysis performed via neutron activation analysis.

Main Results:

• Optimized differential centrifugation at 400 x g for 8 min yielded high platelet purity (erythrocytes/platelets < 5 mg/g, leukocytes/platelets < 20 mg/g).
• Trapped plasma was quantified at approximately 0.40 g/g in wet platelet samples.
• Neutron activation analysis confirmed no significant contamination for a range of elements (Ag, Cd, Co, Cr, Cs, Cu, Fe, Mo, Rb, Sb, Se, Zn).

Conclusions:

• The developed method effectively isolates pure and viable platelets suitable for trace-element analysis.
• The protocol minimizes contamination and accurately corrects for trapped plasma, enhancing the reliability of elemental quantification in platelets.