Application of atomic force microscopy in blood research.
OBJECTIVE
To find suitable solutions having lesser granules and keeping erythrocytes in normal shapes under atomic force microscopy (AFM).


METHODS
Eight kinds of solutions, 1% formaldehyde, PBS buffer (pH7.2), citrate buffer (pH 6.0), 0.9% NaCl, 5% dextrose, TAE, 1640 medium and 5% EDTA-K2, were selected from commonly used laboratory solutions, and venous blood from a healthy human volunteer was drawn and anticoagulated with EDTA-K2. Before scanned by AFM (NanoScopeIIIa SPM, Digital Instruments, Santa Barbara, CA), a kind of intermixture was deposited on freshly cleaved mica and then dried in the constant temperature cabinet (37 degrees).


RESULTS
One percent formaldehyde, citrate buffer, 5% dextrose, TAE, were found to keep human erythrocytes in normal shape with few particles. Processed by these solutions, fine structures of human erythrocyte membrane were obtained.


CONCLUSIONS
One percent formaldehyde, citrate buffer, 5% dextrose and TAE may be applied to dispose erythrocytes in AFM. The results may offer meaningful data for clinical diagnosis of blood by AFM.
Ji
Xiao-Long
XL
Institute of Nanomedicine, General Hospital of Chinese People's Armed Police Forces, Beijing 100039, China. xlji@greenbeijing.com
Ma
Ya-Min
YM
Yin
Tong
T
Shen
Ming-Shi
MS
Xu
Xin
X
Guan
Wei
W
D002021:Buffers; D048430:Cell Shape; D004910:Erythrocyte Membrane / Q000648:ultrastructure*; D004912:Erythrocytes / Q000648:ultrastructure*; D005404:Fixatives; D005557:Formaldehyde; D006801:Humans; D018625:Microscopy, Atomic Force / Q000379:methods*; D012996:Solutions
D002021:Buffers; D005404:Fixatives; D012996:Solutions; D005557:Formaldehyde