Guidance in using an average density to simulate platelets for validations
After reading our VUEPOINT post – “Simulated Blood Products: 10% Glycerol in water may NOT be “One Size Fits All” – that presented “recipes” for simulated blood products (Red Blood Cells, Whole Blood and Plasma) – one of our VUEPOINT readers recently posted a comment on our website. The question was about platelets, asking for the water-glycerol mixture for simulating them, just like we had done for the other blood products. Great question and we’re glad you asked!
How do we calculate an accurate mixture based on varying platelet densities?
Because of the density range of platelets, if you were striving to be highly, highly accurate, you would need to know what group the platelets fall into. Various professional papers discuss high, low and other density groups. Here is a reference from the University of Virginia School of medicine that classifies platelets into three Density Classes, with an average density for each class.
Another platelet density analysis reported “…normal platelets layered onto Percoll formed a band extending from 1.0625 g/ml to 1.0925 g/ml, with a mean platelet density of 1.0775 g/ml:…”.1
In response to our VUEPOINT reader’s inquiry, we have modified our graph and recommended water-glycerol mixture (1.066, 26%) to include a formula for platelets. This graph plots the % Glycerol (y-axis) to Density / Specific Gravity (x-axis), which reflects density, for Plasma, Whole Blood, Platelets and RBCs.
Recommended “Recipes” for simulated blood products
Based on the data presented in this VUEPOINT, we recommend that you consider using the following mixtures for blood product simulation.
Stir for a few minutes to assure a homogeneous solution. Be sure to follow any precautions supplied by the glycerol manufacturer for handling pure glycerol.
Other Sources for Platelet Density Information
For those of you who are interested in digging a little deeper into platelet density, here is a link to another reference that reports blood density determination:
Blood. 1977 Jan;49(1):71-87. Heterogeneity of human whole blood platelet subpopulations. I. Relationship between buoyant density, cell volume, and ultrastructure. Corash L, Tan H, Gralnick HR.
Please Share Your Questions and Feedback
We always appreciate questions like these that give us an opportunity to do some research and share more valuable information, with the goal of making your job a little easier if we can. Please don’t hesitate to post a COMMENT to any of our VUEPOINT articles if you have something to share, or would like to us to “dig a little deeper” for our mutual learning.
1 Platelet-Density Analysis and Intraplatelet Granule Content in Young Insulin Dependent Diabetics, A. Collier, H.H. K Watson, D.M. Matthews, L. Strain, C.A. Ludlam, and D.F. Clarke, Diabetes, Vol. 35, October 1986.