Acid-washed coverslips

Seed cells onto a sterile no. 1.5 acid-washed glass coverslip with an electrotaxis chamber similar to Fig. 3. 

For autoradiography, cells were plated onto coverslips in Falcon plastic dishes. After 24 hr of growth, H -hypoxanthine (1.5 C//Limole) was added at a concentration of 5 aC/ml. After 16 hr of growth, coverslips were removed, washed with saline, and fixed in methanol for 5 min. The coverslips were then treated with ice cold 5 % trichloracetic acid for 25 min, washed in water, and dried. The coverslips were dipped in Sakura NR-M2 liquid emulsion, and after exposure for 1 week, the autoradiographs were developed. 

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