Investigation of a Potential Mineral-Based Disease Control Agent

Waterborne disease resulting from bacteria in drinking water supplies is an aspect of human health that has received wide attention. One approach to disease control is to use antibacterial agents in water resources; however several disadvantages exist in using technologies based on organic molecules, or heavy metals. A potential alternative approach is to use clay minerals combined with other materials that may have antibacterial properties.

We investigated mineralogical aspects of a palygorskite deposit from southern Quintana Roo, Mexico. The mineralogy consists of approximately 85% palygorskite, 15% montmorillonite and has trace quantities of titanium oxides. The clay forms good suspensions and no environmentally suspect minerals such as sulfides, sulfates or heavy metal-rich phases occur. The chemical composition of palygorskite and montmorillonite are typical. Palygorskite fibers are straight and predominantly euhedral in nature. Fibers vary in width from approximately 20 nm to 65 nm, however most fibers are commonly 45 to 50 nm in width. Fiber length varies from approximately 0.3 to 3.0 µm. The fiber terminations are commonly well developed and euhedral. Selected area electron diffraction (SAED) patterns taken along (hk0) of fibers commonly show discrete spots with minor streaking. Montmorillonite particles are predominantly subhedral lamellar aggregates with diameters that vary from 0.1 to 0.5 μm. SAED patterns from montmorillonite particles are weak concentric rings.

The source is desirable, being near potential outbreak sites in Central America. Development of this resource would have a positive impact on an economy that to date is dominated by tourism. This material may be suitable as a carrier agent for nanoparticles having antibacterial properties, such as transition metal oxides. This investigation is the first stage feasibility study towards developing inexpensive materials for disease control that would not result in antibiotic resistant bacteria.