Feldmann, E.G.The Colorimetric Determination of Certain Local Anesthetics with Sodium 1,2-Naphthoquinone-4-sulfonate, J. Am. Pharm. Assoc., Sci. Ed., 48:197, 1959.
2.
Feldmann, E.G. , and Koehler, H.M.The Colorimetric Determination of Lidocaine with cis-Aconitic Anhydride, J. Am. Pharm. Assoc., Sci. Ed. , 48:549, 1959.
3.
Sass, S., Kaufman, J.J., Cardenas, A.A., and Martin, J.J.Colorimetric Estimation of Tertiary and Quaternary Amines, Anal. Chem., 30:529, 1958.
4.
Eissner, W.Colorimetric Determination of Novocaine and Anesthesine with β-Naphthol, Arch. Pharm., 268:322, 1930.
5.
Seydlitz, H.Colorimetric Determination of Procaine and Para-aminobenzoic Acid in Mixtures, Svenska Farm. Tidskr., 50:65, 1946.
6.
Ting, K.S., Coon, J.M., and Conway, A.C.Spectrophotometric Method for Determination of Procaine and Para-aminobenzoic Acid, J. Lab. Clin. Med. , 34:822, 1949.
7.
Oelssner,W. ColorimetricDetermination of Procaine and Para-aminobenzoic Acid, Pharmazie, 7:133,1952.
8.
Chakravarti, S.N., and Roy, M.B.New Colorimetric Test for Procaine and Primary Amines, Analyst, 62:603, 1937.
9.
Yamagishi,M. ColorimetricDetermination of Procaine, Ann. Repts. Takeda Research Lab., 10:35, 1951.
10.
Riegel, E.R., and Williams, J.F.New Color Reaction for Procaine and Some Other Local Anesthetics and Its Application to the Determination of Procaine, J. Am. Chem. Soc., 48:2871, 1926.
11.
Jannke, P.J.The Assay of Benzocaine, Pharm. Arch., 16:25, 1945.
12.
Vallejo, S.R.The Determination of Aminated Drugs by Diazotization , Rev. quim. farm. (Santiago, Chile), 8:5, 1951.
13.
Pratt, E., L. Spectrophotometric Titrations with Nitrous Acid. I. The Estimation of Procaine Hydrochloride, Propoxycaine Hydrochloride, and Tetracaine Hydrochloride , J. Am. Pharm. Assoc., Sci. Ed., 46:724, 1957.
14.
Mitchell, J., JR., Hawkins, W., and Smith, D.M.Analytical Procedures Employing Karl Fischer Reagent. XI. The Determination of Primary Plus Secondary Amines, J. Am. Chem. Soc., 66:782, 1944.
15.
Ogg, C.L. , Porter, W.L., and Willits, C.O.Determining the Hydroxyl Content of Certain Organic Compounds. Macro- and Semimicromethods, Ind. Eng. Chem., Anal. Ed., 17 :394, 1945 ; as extended in Siggia, S.Quantitative Organic Analysis via Functional Groups, chap. 10, pp. 107, 108, 117. 2d ed. New York: John Wiley & Sons, 1954.
16.
Koehler, H.M. , and Feldmann, E.G.Qualitative Identification of Local Anesthetics in Their Dosage Forms, Anal. Chem., 32:28, 1960.
17.
Duke, F.R.Metallo-organic Complexes in Organic Analysis: Some Qualitative Tests for Amines, Ind. Eng. Chem., Anal. Ed., 17:196, 1945.