Government of the United States of America, As Represented by the Secretary of Commerce

USA As Represented by Secretary of the Navy

The United States of America, As Represented by the Secretary, Department of Health and Human Services

The United States of America As Represented by the Secretary of

Francis W Wang

Charles L Thomas

Anthony J Bur

Robert E Lowry

Joseph L Rose

Stephan P Velsko

Steven C Roth

King-Fu Lin

Kenneth M Yamada

Andrew D Doyle

The present invention employs the natural hydrophilic properties of a macromolecular film such as a hydrogel and in combination with localized photo-ablation of monolayers created with the hydrogel using multi-photon laser excitation, provides a stampless, versatile method of micropattern fabrication.

Micropatterning of biological molecules using laser ablation

The change in the peak fluorescence wavelength of a small amount of a fluorescent compound, i.e., a fluorophore, which has been dissolved in a polymerizing material or a thermoplastic polymer is used to determine the extent of cure or solidification, respectively. The measured wavelength-shift can either be compared with a previously determined correlation to obtain an absolute value for the extent of cure, or can be utilized to compare or maintain an acceptable extent of cure throughout a manufacturing or a clinical process. Similarly, in the processing of a thermoplastic polymer by injection molding, the measured wavelength shift can either be compared with a previously determined correlation to obtain an absolute value for the temperature of the polymer, or can be utilized to adjust the injection molding cycle so that the mold is opened at the optimum times. The fluorophores used in the method are preferably selected from a class of fluorophores comprising alpha, omega substituted linear alkenes having an electron accepting group attached at the alpha position and an electron donating group attached at the omega position.

Non-destructive method for determining the extent of cure of a

A method is provided for measuring the onset of polymer solidification, i phase transitions from liquid to crystal or liquid to glass, during injection molding to detect characteristic fluorescence radiation from a dye which has been doped into the polymer at very low concentration. The method involves the use of a calibration relationship between the fluorescence intensity and temperature of the doped polymer in order to determine distinct features which characterize the onset of solidification.

Method for detecting thermodynamic phase transitions during polymer

A method of measuring fluid properties of a polymer melt, undergoing shear and/or extensional flow which utilizes fluorescent anisotropy. The method utilizes a polymeric chromophore which includes a bifunctional anthracene that is covalently bonded to polybutadiene. The invention also involves an optical probe which is designed to be inserted into existing temperature and/or pressure probe ports in processing equipment. The probe includes a rotatable polarizer and emission collection fibers.

Optical sensor for the measurement of molecular orientation and

A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a 'harmonic generating unit' which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

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Gaithersburg, MD, United States of America

Francis W Wang