Table 1. Qualitative appraisal of different specimen preparation protocols with effects on the degree of preservation quality (pres.) and contrasting (cont.) of selected subcellular structures visible at the acquired magnification.
| Cellular structures | SCF |
GOT |
TAMOI |
ROUM |
NCMIR |
|||||
|---|---|---|---|---|---|---|---|---|---|---|
| Pres. | Cont. | Pres. | Cont. | Pres. | Cont. | Pres. | Cont. | Pres. | Cont. | |
| Plasma membrane | + | + | + | + | ++ | ++ | ++ | ++ | +++ | +++ |
| Rough endoplasmic reticulum | + | − | + | − | + | + | +++ | ++ | +++ | +++ |
| Mitochondria | ± | − | ± | − | + | + | ++ | ++ | +++ | +++ |
| Lipid droplets | ++ | + | + | ++ | +++ | +++ | +++ | +++ | +++ | ++ |
| Glycogen | nv | nv | nv | nv | + | + | +++ | ++ | +++ | +++ |
| Nuclear membrane | + | ± | + | + | ++ | + | +++ | ++ | +++ | +++ |
| Chromatin | ++ | ± | ++ | ± | +++ | ++ | +++ | +++ | +++ | +++ |
| Nucleoli | ++ | + | + | + | ++ | + | +++ | + | +++ | +++ |
Criteria used in assessing fixation quality based on morphology: (nv) not visible; (−) poor; (±) satisfactory; (+) good; (++) very good; (+++) excellent.
SCF, standard chemical fixation; GOT, glutaraldehyde-osmium tetroxide-tannic acid; TAMOI, tannic acid mediated osmium impregnation; ROUM, reduced osmium and en bloc uranyl acetate method; NCMIR, National Centre for Microscopy and Imaging Research.