Color and Dyes

Predicting the color of a dye when in an environment such as hair is only part of the challenge. It is necessary to consider how the pigment will get to the point of interest. Will it adhere? Will it remain in position over time? Accelrys software tools and Contract Research & Scientific Consulting Services can help with determining answers to such questions.

Color Prediction

Predicting the color of a molecule involves calculating the optical absorption spectrum in it's native environment. Materials Studio software modules such as Forcite Plus and VAMP can be used to provide initial structures and predict the UV spectra.

Related Software and Services:

• Materials Studio Forcite - advanced classical molecular mechanics tool
• Materials Studio VAMP - semi-empirical molecular orbital package for molecular organic and inorganic systems
• Contract Research & Scientific Consulting Services - through access to our full suite of modeling and simulation software, experts at Accelrys can help you with you color prediction efforts

Related Case Study:

Optical Absorption Spectra of Melanins - a Comparison of Theoretical and Experimental Results

Transport and Miscibility

Transport of the dye through channels in the hair can be simulated directly using atomistic modeling tools. Compatibility, or miscibility, between the dye and the host is important to improve the binding properties of the dye and host. Materials Studio software modules such as Forcite Plus and Amorphous Cell can be used to predict the compatibility between host and dye.

Related Software and Services:

• Materials Studio Forcite Plus - classical simulation, molecular dynamics and analysis tools
• Materials Studio Amorphous Cell - comprehensive set of model construction, simulation, and analysis tools for predicting properties of amorphous systems
• Contract Research & Scientific Consulting Services - through access to our full suite of modeling and simulation software, experts at Accelrys can help you with you studies of dye transport and miscibility

Related Case Study:

- Molecular Modeling Studies of Polymeric Transdermal Adhesives: Structure and Transport Mechanisms

Reactivity

In some cases, the dye molecule is too insoluble or to big to diffuse on an appropriate time scale. In these situations, dyes can be delivered as smaller fragment molecules that subsequently react to form the dye in-situ. Accelrys' quantum mechanics tool, DMol³, can be used to examine the reactivity of the fragment molecules at their reactive site.

Related Software and Services:

• Materials Studio DMol³ - density functional theory (DFT) quantum mechanical code to simulate chemical processes and predict properties
• Contract Research & Scientific Consulting Services - through access to our full suite of modeling and simulation software, experts at Accelrys can help you with you studies of dye reactivity

Bibliography: Color and Dyes

1. Jacobson, S. H., "Molecular Modeling Studies of Polymeric Transdermal Adhesives: Structure and Transport Mechanisms", Pharmaceutical Technology, 122-130, September 1999.
2. Stark, K. B.; Gallas, J. M.; Zajac, G.W.; Eisner, M.; Golab, J. T.,J. Phys. Chem. B, 2003, 107, 3061.
3. Barto, R. R.; Frank, C.W.; Bedworth, P. V.; Ermer, S.; Taylor, R. E.Proc.J. Phys.Chem. B, 2004,108, 8702.