Folahan O. Ayorinde

Professor
Organic Chemistry

fayorinde@.howard.edu
202-806-6900 (Voice)
202-806-5442 (FAX)

B. S. 1975 St. Louis University
M. S. 1977 St. Louis University
Ph.D. 1980 Howard University

Current Research Interest

Mass Spectrometric Characterization and Synthetic Applications of Triacylglycerol Oils.

Development of Analytical Protocols for non-proteinaceous, Low-molecular weight (100 - 5000 Daltons) compounds using Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry.

Syntheses of Oleochemical-based Surfactants.

State-of-the-art Analytical Technology (MALDI-TOFMS) at Howard's Department of Chemistry Enables a Convergence of Scientists from Different Disciplines.

MALDI-TOFMS

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) is a state-of-the-art technology that was originally designed for the analysis of proteins, peptides, nucleotides, oligosaccharides and other biomolecules, and in some cases, synthetic polymers. However, recent commercial introduction of delayed-extraction technology into the MALDI ion source has resulted in a much improved resolution (5-10K), particularly for molecules with masses less than 5000 Daltons, and thus enabling the analysis of complex mixtures of low-molecula r weight oligomers, organo-metallics, lipids, surfactants, and countless other organics. MALDI-TOFMS is a soft-ionization process that provides mostly molecular ions, due to the fact that the analyte molecules are enveloped with in a crystalline matrix that absorbs most of the laser energy. Some of the absorbed laser energy is then used to aid in the ionization of the analyte molecules. Because MALDI is coupled with the time-of-flight (TOF) mass analyzer, there is no theoretical limit to its mass range, however, for practical purposes (primarily due to detector limitation), experimental molecular weight determination usually range from 100 Da to 200,000 Da for most commercial instruments. The TOF mass anal yzer acts pretty much like a chromatographic system that allows the resolution of complex mixtures of peptides, polypeptides, lipids, oligomers, and other analytes having different molecular ions. Thus, there is increasing awareness that MALDI-TOFMS can be used in the characterization of a broad range of molecules that are hitherto difficult or impossible to analyze by gas chromatography, high performance liquid chromatography, and electrospray ionization mass specrometry. Because of the relative simplicity and versatility of MALDI-TOFMS, investigators from the Departments of Biology, Biochemistry, Chemistry, Civil Engineering, and Pharmacy converge in the Department of Chemistry, which houses the MALDI-TOF facility at Howard University.

Research Associate: Lilly Wan, Graduate Students: David Ejeh, Quentin Keith, and Eisa Elhilo in the MALDI-TOFMS Laboratory

Schematic showing the cross section of the Perkin Elmer DE STR MALDI-TOFMS (courtesy PE Biosystems)

MALDI-TOF mass spectrum of a commercial polysorbate formulation showing four distinct bell-shaped distributions consisting of isosorbide polyethoxylates, polyethylene glycol monoesters, sorbitan polyethoxylates, and polysorbate monoesters.

MALDI-TOF mass spectrum of cationic surfactants from a commercial formulation consisting of dioctyl dimethyl ammonium chloride, decyl octyl dimethyl ammonium chloride, decyl benzyl dimethyl ammonium chloride, didecyl dimethyl ammonium chloride, myristyl benzyl dimethyl ammonium chloride, and cetyl benzyl dimethyl ammonium chloride.

MALDI-TOF mass spectrum of a commercial soap formulation consisting of sodium laurate, sodium myristate, sodium palmitoleate, sodium palmitate, sodium linoleate, sodium oleate, and sodium stearate.

A Chemical Technology Research Program was established in 1988 through initial funding from the Howard University Graduate School. This program focuses on the industrial utilization of vegetable oils with respect to their synthetic and biological transformation into useful chemical intermediates. Thus we embrace all of the conventional areas of organic chemistry, which include: mass spectrometry, nuclear magnetic resonance spectroscopy, gas chromatography, synthesis and isolation.

The overriding objective is to continue to develop a viable and ultimately self-supporting Chemical Technology Research Program in the Department of Chemistry. Initially, the program has focused on developing new analytical procedures, and also improving on existing analytical methods in order to routinely screen commercial fat-based products for the constituent fatty acids and component glycerides. Comprehensively, the program has focused on four areas of commercial interest:

• Routine mass spectrometric characterization of such items as salad oils, shortenings, butter, cheese, chocolate, fried products from commercial sources.
  
• Biological Production of polyester plastics from vegetable oils..
  
• Industrial utilization of fats and oils. The focus here is to transform vegetable oils into chemicals and products that have commercial applications. Emphasis will be placed on the utilization of new vegetable oils with unique triglyceride composition (e.g., Vernonia Oil, see below).
  
• Synthesis and characterization of a series of oleochemical-based surfactants.

Support for our research has come from a $200,000 grant from USAID, a $50,000 grant from USDA and $60,000 from the Howard University Faculty Research Fund. Additionally, through collaboration with Dr. Winston Anderson (Dept. of Biology), we received a three-year (1993-1996) grant for $768,000 as part of a Research Careers for Minority Scholars Program. In 1996-1998 we had a $540,000 grant from Howard University Mordecai Johnson Award in collaboration with four other scientists in the departments of chemistry, biology, engineering and biochemistry. The project focused on the production and characterization of biodegradable and biocompatible polyester plastics. In August 1998, a Perkin-Elmer Voyager-DE STR matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer was purchased with $199,000 NSF/Chemical Instrumentation grant and a $120,000 matching fund from Howard University. At present most of our research is focused on the oil of Vernonia galamensis with respect to the following areas of potential commercial interest. In November, 1998 we received a $10,000 award from Rohm and Haas Company, Springhouse, PA, in support of our research program.

...........Vernolic Acid (major acid component of vernonia oil)

- Processing of the oil: This includes extraction, refining and bleaching.

- Syntheses: Use of the oil in the syntheses of vernolic acid, dibasic acids, monobasic acids, nylon-11, nylon-12 monomers, and oleochemicals. Many of these products have established markets in the polymer and chemical industries. However, most of these industrial chemical intermediates are currently obtained from petrochemical sources.

Surfactants: Use of the oil in the synthesis of surface active agents that are used in various consumer products such as: detergents, body lotion, shampoos, house-hold cleaners, cosmetics.

-Biodegradable Plastics: This is concerned with the use of vernonia oil and other vegetable oils in the production of biodegradable and biocompatible polyester plastics.

Graduate Student: Karen Garvin with the Hewlett Packard HPLC/Particle Beam/MS

PATENTS

We have recently been granted several US patents that deal with potential industrial processes or syntheses of potential industrial chemicals. These patents include:

US Patent No. 5,414,100

This invention is concerned with a process in which vegetable oils are deacidified by passing solutions of the oils in rubbing alcohol (2-propanol) through a column of activated alumina (aluminum oxide). Additionally, a process was developed by which the "used" alumina can be reactivated for subsequent use.

US Patent No. 5,434,307

This invention relates to the synthesis of 12-oxododecanoic acid oxime, a novel aldoxime, which can be used as the starting material for the production of several important monomers. More specifically, this invention relates to a process by which vernolic acid (cis-12,13-epoxy-cis-9-octadecenoic) is transformed into 12-oxododecanoic acid oxime, which can be further transformed into 12-aminododecanoic acid, the monomer for Nylon-12.

US Patent No. 5,491,244

This invention relates to a process in which olefin acid anhydrides are produced by the reaction of an acid chloride and a carboxylate ion corresponding to the olefin acid anhydride to be produced. The process may be conducted without the use of an external source of heat, without catalysts, without polymerization inhibitors and without solvent. This invention also relates to a process wherein acrylic acid anhydride or methacrylic acid anhydride is produced by reacting an aromatic acid chloride with the corresponding carboxylate ion of acrylic acid anhydride or methacrylic acid anhydride. The above anhydrides can subsequently be reacted with alcohols at room temperature, without the need for any catalyst, to give high yields of the corresponding acrylate esters.

US Patent No. 5,498,733

This invention relates to 11-aminoundecanoic acid, the Nylon-11 monomer. More specifically, this invention relates to a process by which 12-oxododecanoic acid oxime which is derived from Vernonia oil, is transformed into 11-aminoundecanoic acid.

US Patent No. 5,530,148

This invention relates to the synthesis of 12-oxododecanoic acid oxime, a novel aldoxime, which can be used as a the starting material for the production of several important monomers. More specifically, this invention relates to a process by which vernolic acid is transformed into 12-oxododecanoic acid oxime, which can be further transformed into 12-aminododecanoic acid, the monomer for Nylon-12.

Visitors in our lab. (below)

Kellie Pentz, Elizabeth DiTondo, Joe Kosman, and John Pratt, studying some MALDI-TOFMS Data during a visit to the Howard University MALDI Laboratory. K.P., E.D., and J.P. are from Perkin-Elmer Biosystems. J.K is from W.L Gore and Associates.

Some Representative Non-MALDI Publications

F. O. Ayorinde, J. W. Wheeler, R. M. Duffield, "Synthesis of Dehydrocineole: A New Monoterpene from the Acarid Mite, Caloglyphus rodriguezi (Arachnida: Acari)," Tetrahedron Lett., 25 (1984) 3225.

F. O. Ayorinde, "Determination of Stereochemical Relationship," J. Chem. Educ., 62 (1985) 297.

F. O. Ayorinde, M. Shamim, "The Synthesis of Isomerically Pure 6-methylsalicyaldehyde," J. Chem. Soc., Pak., 7 (1985) 69.

O. A. Afolabi, F. O. Ayorinde, O. L. Oke, "Preliminary Nutritional and Chemical Evaluation of Raw Seeds from Mucuna Solanei - An Underutilized Food Source," J. Food and Agric., 33 (1985) 122.

F. O. Ayorinde and F. T. Powers, "Synthesis of Azelic Acid and Suberic Acid from Vernonia galamensis Oil," J. Am. Oil Chem. Soc., 65 (1988) 1774.

F. O. Ayorinde, J. Clifton, Jr., O. A. Afolabi and R. L. Shepard, "Rapid Transesterification and Mass Spectrometric Approach to Seed Oil Analysis," J. Am. Oil Chem. Soc., 65 (1988) 942.

F. O. Ayorinde, F. T. Powers, L. D. Streete, R. L. Shepard and D. N. Tabi, "Synthesis of Dodecanedioic Acid from Vernonia galamensis Oil," J. Am. Oil Chem. Soc., 66 (1989) 690.

O. A. Afolabi, M. E. Aluko, W. A. Anderson, and F. O. Ayorinde, "Synthesis of Toughened Elastomer from Vernonia galamensis Oil," J. Am. Oil Chem. Soc., 66:983 (1989).

F.O. Ayorinde, C. P. Nwaonicha, V.N. Parchment, K.A. Bryant, and M.T. Clayton, "Enzymatic Synthesis and Spectroscopic Characterization of 1,3-Divernoyl Glycerol from Vernonia galamensis Seed Oil". J. Am. Oil Chem. Soc., 70:129 (1993).

K.A. Bryant, C.P. Nwaonicha, M. Hassan, M.A. Anderson, and F.O. Ayorinde, "Synthesis and Isolation of Epoxy Secondary Amides via Direct Amidation of Vernonia galamensis Seed Oil". J. Am. Oil Chem. Soc., 70:457 (1993).

F.O. Ayorinde and M. Hassan, "Deacidification of Vegetable Oils", U.S. Patent 5,414,100 (1995).

C.P. Nwaonicha and F.O. Ayorinde, "Synthesis of 12-Oxododecanoic Acid Oxime from Vernolic Acid", U.S. Patent 5,434,307 (1995).

C.P. Nwaonicha and F.O. Ayorinde, "Synthesis of 12-Aminododecanoic Acid", U.S. Patent 5,530,148 (1996).

F.O. Ayorinde and C.P. Nwaonicha, "Synthesis of Nylon-11 Monomer", U.S. Patent 5,498,733 (1996).

F.O. Ayorinde and M. Hassan, "Synthesis of cis-12,13-epoxy-cis-9-octadecenyl acrylate", U.S. Patent 5,491,244 (1996).

F.O. Ayorinde, E.Y. Nana, P.D. Nicely, A.S. Woods, E.O. Price, and C.P. Nwaonicha, "Syntheses of 12-Aminododecanoic and 11-Aminoundecanoic Acids from Vernolic Acid", J. Am. Oil Chem. Soc., 74:531 (1997).

F.O. Ayorinde, K.A. Saeed, E. Price, A. Morrow, W.E. Collins, F. McInnis, S.K. Pollack, and B.E. Eribo, "Production of Poly(beta-hydroxybutyrate) from Saponified Vernonia galamensis Oil by Alcaligenes eutrophus". J. Ind. Microbiol. Biotechnol, 21, 46-50 (1998).