348 TISSUE CULTURE 



growth of a tissue in nutrient media. All glass containers should 

 be of hard glass, paraffin coated and plugged with rubber or 

 paraffined corks to prevent gaseous exchange. Only purified 

 analytical reagents should be used. The solutions are made up 

 in double distilled water and the salts added separately, in strict 

 order, allowing each to dissolve before the next is added. 



T'yrode solution (for warm-blooded animals). (Tyrode, Arch. 

 Internat. Pharmacodyn., xx, 1910, p. 205.) 



. 8-00 grm. 



. 0-20 ., 



NaCl . 

 KCl . 

 CaClg, 6H2O 

 MgClo, 6H0O 

 NaH2P04,"4HoO 

 NaHCOg . " 

 Glucose 

 Aq. dest. 



. 0-395 ,, 

 . 0-213,, 

 . 0-05 „ 

 . 10 „ 

 • 10 „ 

 1000-0 c.c. 



Weigh each salt on an analytical balance or make up concentrated 

 solutions and add the calcvilated volume of each solution to the 

 remaining distilled water. All salines containing NaHC03 must 

 be sterilised by a Berkefeld or Seitz filter, not by autoclaving. 

 The best time to sterilise the solution is immediately after mixing. 

 Then test the ^H which should be between 7-6 and 7-8. Loss of 

 COg through faulty stoppers will render it more alkaline. 



Pannett and Compton saline. (See Pannett and Compton, 

 Lancet, i, 1924, p. 381.) 



This saline is widely used in England and has the advantages 

 of withstanding autoclave sterilisation and of rapid adjustment of 

 its pH. Make up Solution A : 



NaCl 8-0 grm. 



KCl 0-42 „ 



Aq. dest. ..... 100-0 c.c. 



Solution B : 



Na2HP04, I2H2O. . . . 0-43 grm. 



NaHaPO^, 4H2O .... 0043 „ 

 Aq. dest. ..... 100-0 c.c. 



Take 88 c.c. of double distilled water and add 8 c.c. of solution A. 

 Measure 4 c.c, of solution B into a small flask and autoclave the 

 separate solutions. After cooling add B to A with a sterile pipette. 

 The proportion of acid phosphate may be varied slightly to give 

 a required pH. See Norfield (Lab. Journ., vi, 1930, p. 320) for 

 variation of this formula. 



Locke-Lewis solution. (See Lewis and Lewis, Anat. Rec, v, 

 1911, p. 277.) 



This saline has been much used for culturing in a fluid medium 

 without the addition of embryonic extracts or plasma. 



