Clinical Chemistry, Vol 28, 708-708, Copyright © 1982 by the American Association for Clinical Chemistry

Advantages of Use of Ascorbic Acid and Sodium Lauryl Sulfate in the Microdetermination of Serum the Inorganic Phosphorus

¹ Proyecto UNDP/FAO-INTA ARG/75/023 Casilla de Correo 228 4400 Salta, Argentina

Vol. 27

p 639: In the second paragraph of the middle column, the third sentence (et seq.) should read as follows: In the method of Chen et al. (12), modified to include SLS 1,040 mmol/L, 25 µL of serum was added to 25 µL of distilled water. To this was added 200 µL of a solution of SLS containing 1040 mmol/L, followed, after mixing, by 2.50 mL of a reagent consisting of 3.1 g of ammonium molybdate per liter of 375 mmol/L sulfuric acid. To avoid any instability in the reducing capacity of ascorbic acid if mixed in advance with molybdate and sulfuric acid (14), we added it separately—0.200 mL of a 150 g/L solution in glass-distilled water. After incubation in a warm bath at 37 °C for 140 min (12), the replicated stoppered samples were cooled and their absorbances (820 nm, 1-cm cells) read immediately and 3 and 18 hlater. In those cases where SLS was not used—i.e., in the unmodified method (12)—50 µL of a prepared trichloroacetic acid extract, equivalent to 25 µL of serum, was analyzed in the same manner; 200 µL of distilled water then replaced the SLS.

p 1401: In footnote 1, the compound should read N¹-(,-dimethyl - - hydroxyethyl) - 2- methyl - 1,2- propanediamine.

p 1749: In Table 3, column 4, row 2: "0-20" should read "0-2.0."

p 1948: In ref. 12, "Sud-" should read "Sul-" (publication is in Portugese, not Spanish).

p 1952: The names of two of the authors are misspelled: Cassani and Vanzetti. The correct spellings in the address are "Granda" and "Niguarda."

Vol. 28

p 156: In Table 1, last column, delete "x" from the equations "y = 0.75x" and "y = 1.71x."

p 401: In the address in the middle column, "State" should read "Safe."

p 406: Third column, under "Natelson Award," Normal should read Norman.

p 557: Just before the last sentence in the second paragraph in the middle column, insert the following sentence: "The exact degree of the enhancement depends highly on the amount of catalase impurity in the glucose oxidase preparation."