F 04 Basal Fixative Solutions FIXATIVES 237 



9000.0000 Bank and Davenport 1940 20540b, 15 :9 



formula: water 125, 95% ale. 125, formamide 10, chloral hydrate 6 



9000.1000 Huseby 1946 16913,61:122 



formula: water 225, resorcinol 12 to 20, 40% formaldehyde 25 



9000.4000 Davenport, Windle, and Rhines 1947 Conn and Darrow 1947, Id, 24 



formula: paranitrophenol 12.5, water 112, 95% ale. 112, formamide 25 



F 04 Basal Fixative Solutions 



04.0 EXPLANATION 



These basal fixative solutions were originally suggested by Gray 1933 (11360, 63:13) 

 where he published a brief list of the more common fixatives which could be prepared by 

 their aid. This list was slightly amplified, and formed an appendix to the tenth and eleventh 

 editions of Lee's Microtomisi's Vade Mecum. 



Briefly, the method involves having available standardized solutions, through the mixture 

 and dilution of which it is possible to prepare about 80% of commonly employed fixatives. 

 The original method of Gray involved the preparation of two series of such solutions, known 

 as the aqueous and alcoholic series, but the latter has now been suppressed, since experience 

 has shown it to be impractical. The system of numbering the solutions used in this volume 

 differs from that originally proposed and is based on the numerical classification used in 

 the first part of this chapter. That is, the number designating the stock solution corresponds 

 to the number used to designate this ingredient in the list of formulas which have already 

 been given. All the solutions employed are stable except the osmic acid, the preparation of 

 which is described in the next paragraph. 



References to the original citations of the fixatives, indicated in the following list by the 

 author's name and date only, will be found in the preceding section of this chapter. They 

 may be traced either from the alphabetical index or by taking the first four numbers at the 

 head of the column. This will give, in that order, the numerical designation of the class in 

 which the fixative belongs. The addition of the symbols for modifier and acid is readily 

 made by simple inspection. 



04.1 LIST OF SOLUTIONS 



The following solutions are of sufficient strength to require dilution for the preparation 

 of any of the fixatives shown. The first two columns in this tabular material show the two 

 most commonly employed diluents. The last column shows such other ingredients as must 

 be added to secure the required fixative. It is understood that when the ingredient is liquid, 

 a volume is indicated and when the ingredient is solid, a weight is indicated. 



Solution 1 — 2% osmic acid 



note: This should be prepared in chemically clean glassware in filtered, triple-distilled 

 water, to which has been added enough potassium permanganate (approximately 

 0.01%) to give a faint pink color. This pink color should be maintained b}^ the 

 addition of a few drops of potassium permanganate solution whenever necessary. 



Solution 2 — 1% platinic chloride 



Solution 3 — 7% mercuric chloride 



Solution 4 — 5% copper sulfate 



Solution 5 — a saturated aqueous solution of picric acid. 



Solution 6 — 2% chromic acid 



Solution 7 — 7.5% potassium dichromate 



Solution 8 — 7.5% potassium dichromate and 3% sodium sulfate 



note: This is a triple-strength Miiller's 1859 fixative. The previous solution (7) may 

 be substituted for it by those who do not believe in the efficacy of the sulfate 

 content of Miiller. 



Solution 9 — 40% formaldehyde 



Solution 10 — glacial acetic acid 



