82 MICROSCOPIC TECHNIQUES 



PROCEDURE 



1-6. Same as for alkaline phosphatase (pages 79 and 80). 



7. Incubate the sections for 1-24 hr. at 37° in the substrate 

 medium. 



8. Rinse well in distilled water, followed by 2% acetic acid, and 

 then in distilled water again. 



9-10. Same as for alkaline phosphatase, page 80. 



Result. Sites of the phosphatase activity appear brown or black. 



Glick and Fischer Adaptation to Grains and Sprouts of Gomori 

 Method for Acid Phosphatase 



SPECIAL REAGENTS 



Substrate Medium. Combine the following, shake thoroughly, 

 centrifuge, and use the clear liquid: 4 ml. 0.1 ilf acetate buffer of 

 pH 5.1, 1 ml. 0.1 M lead nitrate, 0.6 ml. distilled water, and 0.4 ml. 

 3.2% sodium-a-glycerophosphate. Booth (1944) showed that the a 

 compound is hydrolyzed more rapidly than the (3 by wheat phos- 

 phatase, and Gomori (1941) found that the a compound has the 

 additional advantage that its lead salt is more soluble than that of 

 the /? at this pH value. Because it was easily available, the mix- 

 ture, containing 52% a and 48% fi of Eastman Kodak Co., was 

 used by Glick and Fischer ( 1945) . 



2% Acetic Acid Solution. 



Ammonium Sulfide Solution. 1 ml. to a Coplin jar of water. 



PROCEDURE 



/, Preparation of paraffin sections. A, Kernel sections: 



1. Soak kernels in water about 7 hr. 



2. For longitudinal sections, cut off a layer from both the crease 

 side and the opposite side of the kernel. For cross sections, cut o& 

 kernel just behind germ. This enables more efficient penetration of 

 liquids. 



3. Let kernels stand overnight in absolute alcohol. In the morn- 

 ing change to a mixture of 1 vol. absolute alcohol -f- 3 vol. n-butyl 

 alcohol. 



4. In the evening transfer to n-butyl alcohol. 



