Research interests primarily focus on utilization of the unique properties and features of organized assemblies (surfactant micelles, cyclodextrins, liposomes and surfactant vesicles, and reverse micelles) and other membrane mimetic agents (organogels and ionenes) to enhance chemical analysis and separation science techniques.  Specific current projects include:

(1) Advances in Cloud Point Extractions:  Upon ionic strength or temperature alteration, aqueous solutions of some micelle and/or polymer solutions can phase separate, with most of the surfactant (or polymer) concentrated in the small volume element of the surfactant-rich (or polymer-rich) phase.  Any analyte species that associates or binds to the micelle/polymer entity will thus be concentrated in that phase.  Such phase behavior (clouding phenomenon) of ordered media systems can be employed to design environmentally friendly extractive / enrichment techniques.  The extension of this approach for the extraction of nanomaterials and microbes as well as recovery of target analytes from “solid” matrices is a particular focus of current research.

(2)  Extractions using Surfactant-  and Chitosan-Based Organogel Materials:  The addition of gelatin to some reversed micelle solutions above a critical temperature results in the formation of elastic (solid) gels, which still retain many of the general and beneficial features of reversed micelle solutions. Likewise, chitosan gel-like materials can be synthesized.  The general properties and characteristics of these materials are being investigated.   In addition, such gels can be used to sorb and concentrate desired analytes in a manner akin to a liquid-liquid extraction or enrichment step prior to spectral or other analysis. Of particular interest is the use of such gels to concentrate and detoxify substances of environmental concern (phenols, anilines, etc.) from aqueous or organic solutions.

Representative Publications:

Cloud Point Extraction with Surfactant Derivatization as an Enrichment Step Prior to Gas Chromatographic or Gas Chromatographic – Mass Spectrometric Analysis, Yoshitaka Takagai and Willie L. Hinze, Analytical Chemistry, 81 (2009) 7113 – 7122.

Evaluation of the Potential of Chitosan Hydrogels to Extract Polar Organic Species from Nonpolar Organic Solvents:  Application to the Extraction of Aminopyridines from Hexane, Valfredo T. de Favere and Willie L. Hinze, Journal of Colloid and Interface Science, 330 (2009) 38 – 44.

Fluorescence in Organized Assemblies, Najma Memon, Aamna Balouch, and Willie L. Hinze, in Encyclopedia of Analytical Chemistry, R. A. Meyers, Ed., John Wiley & Sons Ltd.:  Chichester, UK, 2008, DOI:  10.1002/9780470027318.a5409.pub2; 94 pp. 

Surfactant-Mediated Cloud Point Extractions:  An Environmentally Benign Alternative Separation Approach, Frank H. Quina and Willie L. Hinze, Industrial & Engineering Chemistry Research, 38 (#11) (1999) 4150-4168.