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We are developing photonic crystal glucose sensing materials to continuously monitor relatively high glucose concentrations, such as found in blood. We modified our synthetic fabrication methodologies in order to increase the glucose concentration range and to increase the reproducibility of our PCCA fabrication. We have also advanced our understanding of the sensing response by developing a mechanical method to independently determine the hydrogel cross-link density. Our investigation of the sensing mechanism indicates that glucose binding depends mainly on the boronic acid concentrations and affinities. We determined the binding constant Of 2-fluoro-5-aminophenyl boronic acid for glucose under physiological conditions. We have examined the dependence of glucose sensing upon interferences by other species that ligand to boronic acids, such as lactate and human serum albumin. We examined the stability of our sensors over a period of weeks at room temperature and demonstrated that we could further stabilize our sensing materials by reversibly dehydrating them for storage.

Ultraviolet resonance Raman (UVRR) spectroscopy exciting at ~200 nm was used within the peptide bond pi -> pi* transitions to selectively study the amide vibrations of peptide bonds during alpha-helix melting. Results show that the [3.sub.10]-, and pi-helix/bulge conformations melt prior to melting of pure alpha helices, even though these conformations are proposed to be intermediates, indicating they are much more transient at the higher alpha-helix melting temperature.

We developed new photonic crystal polymerized crystalline colloidal array (PCCA) glucose sensing materials, which operate on the basis of formation of cross-links in the hydrogel. These materials are composed of hydrogels that embed an array of ~100-nm-diameter monodisperse polystyrene colloids that Bragg diffract light in the visible spectral region. The hydrogels change volume as the glucose concentration varies. This changes the lattice spacing, which changes the wavelength of the diffracted light. In contrast to our previous glucose sensing photonic crystal materials, we no longer require [Na.sup.+] chelating agents. These photonic crystal materials are being designed for use in glucose sensing contact lens for people with diabetes mellitus. We describe methods to speed up the response kinetics of these PCCA sensing materials. Rapid-response kinetics is achieved by controlling the elasticity and the hydrophilic--hydrophobic balance of the hydrogel system. A more hydrophobic hydrogel composition is obtained by copolymerizing n-hexylacrylate into an acrylamide--bisacrylamide hydrogel. The response rate significantly increases to where it fully responds within 90 s to the average glucose concentrations found in blood (5 mM) and within 300 s to the average glucose concentrations found in tear fluid (0.15 mM). We find unusual temperature-dependent kinetics, which derive from glucose mutarotation in solution. It is shown that a-D-glucose is the glucose anomer binding to the boronic acid derivative. Care must be taken in any glucose determination to ensure that the glucose mutarotation equilibrium has been established. We have demonstrated that the sensor is responsive to ~0.15 mM glucose concentrations in artificial tear fluid solution.

The solution conformation of poly-L-lysine (PLL) and poly-L-glutamic acid (PGA) in their non-alpha-helical states is examined by using the UV resonance Raman (UVR) spectroscopy. A method is also developed to estimate the distribution of Psi Ramachandran angles for these conformations, which are used to estimate a Psi Ramachandran angle energy landscape.

We developed a polymerized crystalline colloidal array (PCCA) photonic crystal sensing material that senses the organophosphorus compound parathion at ultratrace concentrations in aqueous solutions. A periodic array of colloidal particles is embedded in a hydrogel network with a lattice spacing such that it Bragg diffracts visible light. The molecular recognition agent for the sensor is the enzyme acetylcholinesterase (ACHE), which binds organophosphorus compounds irreversibly, creating an anionic phosphonyl species. This charged species creates a Donnan potential, which swells the hydrogel network, which increases the embedded particle array lattice spacing and causes a red-shift in the wavelength of light diffracted. The magnitude of the diffraction red-shift is proportional to the amount of bound parathion. These AChE-PCCAs act as dosimeters for parathion since it irreversibly binds. Parathion concentrations as low as 4.26 fM are easily detected.

The transport of [Pb.sup.2+] through a sensory gel, a polymerized crystalline colloidal array hydrogel with immobilized benzo-18-crown-6, is important for understanding and optimizing the sensor. Square wave voltammetry at a Hg/ Au electrode reveals many parameters. The partition coefficient for [Pb.sup.2+] into a control gel (no crown ether), [K.sub.p], is 1.00 [+ or -] 0.018 (errors reported are SEM). The porosity, [epsilon], of the gel is 0.90 [+ or -] 0.01. Log [K.sub.c ]for complexation in the gel is 2.75 [+ or -] 0.014. Log [K.sub.c] in aqueous solution for [Pb.sup.2+] with the ligand 4-acryloylamidobenzo-18-crown-6 is 3.01 [+ or -] 0.010 with dissociation rate [k.sub.d] = (8.34 [+ or -] 0.45) x [10.sup.2] [s.sup.-1] and association rate [k.sub.f] = (8.79 [+ or -] 0.025) x [10.sup.7] [M.sup.-1] [s.sup.-1]. The partition coefficient of the ligand 4-acryloylamidobenzo-18-crown-6 into the control gel, [K.sub.p,L] is 2.07 [+ or -] 0.15. The diffusion coefficient of [Pb.sup.2+] in the control gel is 6.72 x [10.sup.-6] [+ or -] 0.12 [cm.sup.2]/s. For the sensor gel, but not control gel, diffusion coefficients are location dependent. The range of diffusion coefficients for [Pb.sup.2+] in the probed locations was found to be (6.1112.60) x [10.sup.-7] [cm.sup.2]/s for 0.91 mM [Pb.sup.2+] and (2.84 - 9.39) x [10.sup.-7] [cm.sup.2]/s for 0.35 mM [Pb.sup.2+]. Lead binding in the sensor gel is slightly less avid than in solution. This is attributed, in part, to the demonstrated affinity of the ligand 4-acryloylamidobenzo-18-crown-6 to the gel. Diffusion coefficients determined for the sensor gel were found to be location dependent. This is attributed to heterogeneities in the crown concentration in the gel. Analysis of diffusion coefficients and rate constants show that diffusion and not chemical relaxation will limit the time response of the material.

Adenylyl cyclase (AC) is a prototypical cell-signaling molecule expressed in virtually all organisms form bacteria to man. 7Clb-S meets basic criteria to serve as a model protein for the Clb region and may be used as a prototype to develop other isoform Clb soluble model proteins.

A versatile procedure to synthesize mono disperse hollow polymer colloid particles which can self-assemble into a crystalline colloidal array (CCA) is developed. These help in confining the reaction inside the hollow particles to fabricate.

We developed an optrode sensing device that utilizes a polymerized colloidal array (PCCA) photonic crystal material. This array diffracts light in the visible spectral region due to the periodic spacing of colloidal particles. The PCCA changes diffraction wavelength due to binding of [Pb.sup.2+] to an 18-crown-6 ether molecular recognition agent. This optrode consists of a probe assembly that contains the PCCA [Pb.sup.2+] sensing film. An inexpensive, commercial diode array spectrometer and a fiber-optic reflectance probe monitors the wavelength of light back diffracted by the PCCA. Liquid inlet and outlet connections are provided to introduce the sample solution and to exchange out nonbinding ions. In low ionic strength solutions, diffraction wavelength shifts are actuated by the binding of the [Pb.sup.2+] to the crown ether to immobilize the [Pb.sup.2+] counterions. In these low ionic strength solutions, a Donnan potential forms to cause an osmotic pressure, which swells the PCCA in proportion to the number density of bound [Pb.sup.2+]. This Donnan potential disappears at high ionic strengths. Thus, no response of the PCCA occurs. Our optrode design allows for the fast removal of nonbound ions from the PCCA by washing with pure water. Since the bound [Pb.sup.2+] ions have a slow off rate from the crown ether, the bound [Pb.sup.2+] PCCA diffraction transiently red shifts during washing, directly in proportion to the sample [Pb.sup.2+] concentration. This transient diffraction red-shift can be used to quantitatively determine Pb2+ concentrations in high ionic strength solutions such as bodily fluids.

We demonstrate a colorimetric glucose recognition material consisting of a crystalline colloidal array embedded within a polyacrylamide--poly(ethylene glycol) (PEG) hydrogel, or a polyacrylamide--15-crown-5 hydrogel, with pendent phenylboronic acid groups. We utilize a new molecular recognition motif, in which boronic acid and PEG (or crown ether) functional groups are prepositioned in a photonic crystal hydrogel, such that glucose self-assembles these functional groups into a supramolecular complex. The formation of the complex results in an increase in the hydrogel cross-linking, which for physiologically relevant glucose concentration blue shifts the photonic crystal diffraction. The visually evident diffraction color shifts across the visible spectral region over physiologically important glucose concentration ranges. These materials respond to glucose at physiological ionic strengths and pH values and are selective in their mode of response for glucose over galactose, mannose, and fructose. Thus, we have developed a new recognition motif for glucose that shows promise for the fabrication of noninvasive or minimally invasive in vivo glucose sensing for patients with diabetes mellitus.

We developed a polymerized crystalline colloidal array photonic material that senses metal cations in water at low concentrations (PCCACS). Metal cations such as [Cu.sup.2+], [Co.sup.2+], [Ni.sup.2+], and [Zn.sup.2+] bind to 8-hydroxyquinoline groups covalently attached to the PCCACS. At low metal concentrations (< [micro]M), the cations form bisliganded complexes with two 8-hydroxyquinolines that cross-link the hydrogel and cause it to shrink, which blue shifts the photonic crystal diffraction. These bisliganded cross-links break at higher cation concentrations due to the formation of monoliganded cation complexes. This red shifts the diffraction. We have extended hydrogel volume phase transition theory in order to quantitatively model the diffraction dependence upon metal concentration. These materials can be used as a dosimeter to sense extremely low metal cation concentrations or as a sensor material for concentrations greater than 1 [micro]M. Metal cation concentrations can be determined visually from the color of the diffracted light or can be determined by reflectance measurements using a spectrophotometer. This sensing material could be used in the field to visually determine metal cation concentrations in drinking water. A color chart would be used to relate the diffracted color to the metal cation concentration.

A carbohydrate sensing material is developed, which consists of a crystalline array incorporated into a polyacrylamide hydrogel (PCCA) with pendent boronic acid groups. The PCCA photonic crystal sensing material responds to glucose in low ionic strength aqueous solutions by swelling and red shifting its diffraction as the glucose concentration increases.

The first synthesis of mesoscopic, monodisperse particles that contain nanoscopic inclusions of ferromagnetic cobalt ferrites is reported. These monodisperse ferromagnetic composite particles readily self-assemble into magnetically responsive photonic crystals that efficiently diffract incident light.

The 204- and 229-nm excited UV resonance Raman spectra of wastewater solutions containing sodium nitrite and nitrate were measured in the concentration range 7 [micro]M to 3.5 mM (0.1-50 ppm nitrogen). The other chemical species present in wastewater do not interfere with Raman measurements of N[O.sub.2]-/N[O.sub.3]- bands. We observe detection limits of < 14 [micro]M (

Research has been conducted on the amino acid peptide Bombolitin III. The dilute solution-phase secondary structure of this peptide has been investigated via the UV resonance Raman and circular dichroism spectroscopies and the results indicate that the formation of the alpha-helical turns can be detected via the UV Raman measurements.

A novel method to fabricate nanocomposite monodisperse SiO2 spheres containing homogeneously dispersed Ag quantum dots. The morphologies of the inclusion are controlled through the photochemical reduction of Silver ions, instead of chemical reduction, in a microemulsion reaction matrix during the hydrolysis of TEO'S.

Research has been conducted on the temperature dependence of the solution conformation of the betanova, a 20-residue beta-sheet polypeptide. The use of the UV resonance Raman spectroscopy excited within the peptide bond electronic transitions and the aromatic amino acid electronic transitions in examining this temperature dependence is described.

Crossing barriers between the peptide alpha-helix and fully random coil conformation were studied using transient UV Raman spectroscopy.

Research is presented concerning the determination of ionic strength and pH through the use of diffraction from a hydrolyzed polymerized crystalline colloidal array in the form of photonic crystal material.

Research was conducted to examine the acid-induced denaturation of horse apomyoglobin (apoMb) between pH 7.0 and 1.8 by means of ultraviolet resonance Raman spectroscopy. The 20 nm ultraviolet Rama spectral amide vibrations were monitored to determine the pH dependence of its secondary structure. The vibrations were used to investigate the pH dependence of the Trp and Tyr solvent exposure as the apoMb alpha-helices melt. Results suggest that Trp 7 may be fully exposed in the apoMb pH 4 intermediate.

A novel hydrogel material featuring a monodisperse face-centered cubic array of spherical water holes has been developed. The embedded array of water holes Bragg diffracts light caused by the refractive index mismatch between the interstitial gel medium and the holes. Experimental results show the first verification of the phenomenon of equilibrium entropic trapping of flexible macromolecules in a polymeric gel matrix. The entropic trapping takes place because the flexible macromolecules maximize their conformational entropy by partitioning from the gel network matrix into the embedded holes.

Research was conducted to investigate the dependence of the energy difference between the trans and cis forms of glycyglycine as well as the activation barrier for the various charged states of Gly-Gly. Results indicate only a modest impact of the charge state on energy differences and activation barriers for simple amides. The lack of differences may possibly have arisen from numerous fortuitously canceling effects.

A study was conducted to describe the synthesis of highly charged fluorinated monodisperse spherical particles with a refractive index of 1.386 from 1H,1H-heptafluorobutyl methacrylate using emulsion polymerization. Well-arranged cystalline colloidal arrays (CCA) were formed after dialysis and ion exchange. The CCA arrangement was locked using a polyacrylamide hydrogel matrix. The product can be used in nanosecond fast optical switching and limiting devices.

The optical nonlinear response of a Bragg diffracting polyacrylamide crystalline colloidal arrays (PCCA) of dyed poly(1H,1H-heptafluorobutyl methacrylate) were described and characterized. Matching of the refractive index of the particles and the diffracted probe energy change was measured as a function of pump beam heating of the PCCA. The system was expected to switch on diffraction in the nanosecond time regime. However, the refraction of incident light was smaller than 97% due to crystalline colloidal array disorder.

We have used UV resonance Raman spectroscopy to study the acid denaturation of horse heart aquometmyoglobin (Mb) between pH 7.5 and 1.5. Raman spectra excited at 206.5 nm are dominated by amide vibrations, which are analyzed by using a new methodology to quantitatively determine the Mb secondary structure. In contrast, the 229-nm Raman spectra are dominated by the Tyr and Trp Raman bands, which are analyzed to examine changes in Tyr and Trp environments, such as exposure to water, hydrogen bonding, and, for Trp, any alterations of the dihedral angle between the Trp ring and its linkage to the protein backbone. We uniquely determined which Mb [Alpha]-helices melt by combining the amide, Tyr, and Trp Raman spectral information with heme absorption spectral information. We calculate that the Mb [Alpha]-helical composition decreases from [approximately]80% at neutral pH to [approximately]19% below pH 3.5. The Trp Raman cross sections dramatically decrease at low pH to values which indicate that they are fully exposed to water; this result indicates that the A helix melts. The Tyr Raman bands are pH independent, which indicates that the G and H helices around the Tyr residues do not melt. The dramatic heine absorption acid denaturation changes indicate major alterations of the heme pocket and changes in heme binding. These results indicate that the A, B, C, D, E, and F helices melt in a concerted fashion, while the antiparallel G and H helices only partially melt.

We have directly determined the amide band resonance Raman spectra of the 'average' pure [Alpha]-helix, [Beta]-sheet, and unordered secondary structures by exciting within the amide [Tau][right arrow][[Tau].sup.*] transitions at 206.5 nm. The Raman spectra are dominated by the amide bands of the peptide backbone. We have empirically determined the average pure [Alpha]-helix, [Beta]-sheet, and unordered resonance Raman spectra from the amide resonance Raman spectra of 13 proteins with well-known X-ray crystal structures. We demonstrate that we can simultaneously utilize the amide I, II, and III bands and the [C.sub.[Alpha]]-H amide bending vibrations of these average secondary structure spectra to directly determine protein secondary structure. The UV Raman method appears to be complementary, and in some cases superior, to the existing methods, such as CD, VCD, and absorption spectroscopy. In addition, the spectra are immune to the light-scattering artifacts that plague CD, VCD, and IR absorption measurements. Thus, it will be possible to examine proteins in micelles and other scattering media.

We report the development of a novel sensing material that reports on analyte concentrations via diffraction of visible light from a polymerized crystalline colloidal array (PCCA). The PCCA is a mesoscopicaily periodic crystalline colloidal array (CCA) of spherical polystyrene colloids polymerized within a thin, intelligent polymer hydrogel film. CCAs are brightly colored, and they efficiently diffract visible light meeting the Bragg condition. The intelligent hydrogel incorporates chemical molecular recognition agents that cause the gel to swell in response to the concentration of particular analytes; the gel volume is a function of the analyte concentration. The color diffracted from the hydrogel film is, thus, a function of analyte concentration: the swelling of the gel changes the periodicity of the CCA, which results in a shift in the diffracted wavelength. We have fabricated a sensor, utilizing a crown ether as the recognition agent, that detects [Pb.sup.2+] in the 0.1 [[micro]meter]-20mM ([approximately]20 ppb-[approximately]4000 ppm) concentration range. We have also fabricated glucose and galactose sensors, utilizing glucose oxidase or [Beta]-D-galactosidase as the recognition elements. The glucose oxidase sensor detects glucose in the 0.1-0.5 mM (18-90 ppm) concentration range in the presence of oxygen and detects as little as [10.sup.-12] M glucose (0.18 ppt) in the absence of oxygen. In addition, this sensor reports on dissolved oxygen concentration from [approximately]1 to 6 ppm in the presence of constant glucose concentrations.

The body-centered cubic (bcc) and face-centered cubic (fcc) crystalline colloidal arrays were studied in terms of their lattice constant and crystal structure. The results revealed an anomalously intense diffraction occurring at half the wavelength of light diffracted by the lattice planes with highest particle density. Such diffraction was found to be more than 10-fold more intense than the primary diffraction at lambda-B and is narrow for light incident that is normal to the bcc or the fcc planes.

A new method for directly quantifying the activation barrier energies for ground state trans-cis isomerization of secondary peptides was developed and applied to N-methylacetamide and glycylgycine in aqueous media. The technique is based on ultraviolet resonance Raman spectroscopy to determine the temperature dependence of the ground state isomerization states. The results proved the dependency of the activation barrier height on the amide substituents.

Single-crystal Raman measurements of the hydrated glycylglycine crystal structure indicated the orientation of the amide pi to pi* transition in the peptide plane at an angle of -46 degrees (+/- 3 degrees) to the amide carbonyl bond, while the carboxylate pi to pi* transition moment was parallel to the line connecting the carboxylate oxygens. These results were consistent with those previously obtained for the glycylglycine crystal.

The dynamics of peptide amide linkages in aqueous glycylglycine and other dipeptides were investigated by ultraviolet (UV) resonance Raman and vacuum UV absorbance spectrometry. The results were similar to those previously observed for pi to pi* charge transfer transition. A charge transfer band at 197 nm resulted from electronic interactions between the amide and carboxylate groups.

Analysis of the UV Raman spectra of N-methylacetamide (NMA) isotopomers reveals the differences between the geometries of ground state and pi-pi* excited state of NMA in water. Variations in the excited state geometry relative to the ground state and ground state normal mode composition changes account for the changes in the resonance Raman enhancement for NMA in non-hydrogen bonding solvents. Elongation of the CO bond in the pi-pi* excited state is high in the non-hydrogen bonded solvents.

Water-in-oil microemulsions produce pure silica spheres that react with tetraethyl orthosilicate to produce spheres of 40 and 80 nm in diameter. Coprecipitation of CdNO3 and ammonium sulfide introduces cadmium sulfide quantum dots in larger silica colloids. Controlled coprecipitation of CdS enables the preparation of various nanoscale complex morphologies. TEM, SEM/EDS, X-ray and light scattering help characterize elements in the mono-disperse silica-cadmium sulfide nanocomposites and particle morphology.

UV resonance Raman spectroscopy and UV resonance Raman saturation spectroscopy detect the changes in the Raman cross sections of tyrosyl (tyr) and tryptophyl (trp) residues of hemoglobin after R-T quaternary structural alterations. Relaxation rates remain unaffected and no significant changes between R and T states is seen.

A study used pyrene as a model polycyclic aromatic hydrocarbon (PAH), because of its non-carcinogenic nature and conformational likeness to benzo (a) pyrene, to preferentially analyze the vibrational spectrum of intercalated or exterior bound pyrene. The new method, called optical decoupling Raman spectroscopy (ODRS), uses an optical pump pulse that preferentially activates the species to selectively depopulate the ground-state of the exterior bound pyrene. The intercalated pyrene nonradiatine relaxation rate drastically riser, and the remaining fluorescence is caused by pyrenes that are probably homo at the DNA minor groove, and not intercalated between bases.

The second part of a two-part series on UV resonance Raman spectroscopy is presented. The method was analytically applied to polycyclic aromatic hydrocarbons. A study on protein structure was presented to illustrateits biological application. Techniques, such as pulsed laser excitation and hyper-Raman scattering, are seen varieties of this method. It is expected that UV-Raman measurements will be facilitated by future instrumental advancements.

Inelastic scattering of light from matter causes the occurence of frequency shifts. The magnitude and intensities of these observed shifts, which can be used to extract information on molecular structure and dynamics, can be measured by raman spectroscopy. The phenomenology, instrumentation and fundamental application of this technique is reported in the first portion of atwo-part series.

The diverse and site-directed mutant hemoglobins and myoglobins studied under vibrational circular dichroism (VCD) spectra featured long-distance electronic interactions between their heme, ligands and distal protein portions. The VCD spectra was sensitive to the antisymmetry stretch of the azide ligand bound to the heme iron. The molecular interactions involved in the ligand binding were similarly detected from the VCD data.

Monodisperse silica spheres having CdS inclusions, on etching CdS inclusion, produce complex monodisperse silica spheres containing voids with identical morphology. Etched silica particles contain craters, spherical voids and hollow cores that separate silica shells from silica cores. CdS patches attach silica spheres to produce ellipsoidal cavities within doublets of silica spheres.

Circular dichroism and UV resonance Raman spectroscopy was employed to study the impact of alcohols on the conformational equilibria and relative Gibbs free energy landscapes along the Ramachandran [Psi]-coordinate of a mainly poly-Ala peptide, AP with an AAAAA[(AAARA).sub.3]A sequence. Alcohols stabilized [pi]-bulge conformation more than the [alpha]-helix, while the [3.sub.10]-helix was destabilized due to the alcohol-increased hydrophobicity and 2,2,2-Trifluoroethanol (TFE) induced more [alpha]-helices, it favored multiple, shorter helix segments.

Circular dichroism, Ultra violet resonance Raman spectroscopy, and molecular dynamics simulation were used to examine the impact of salts on the conformational equilibria and the Ramachandran [Psi] angle (un)folding Gibbs free energy landscape coordinate of a mainly polyalanine [alpha]-helical peptide, AP of sequence AAAAA(AAARA)3A. The decreased [Cl.sup.-] and S[O.sub.4.sup.2-] AP [alpha]-helix stabilization probably resulted from a decreased association with the Arg and terminal N[H.sup.3+] groups and the smaller binding affinity of [Cl.sup.-] stabilized [alpha]-helical conformation intermediately between NaCl[O.sub.4] and [Na.sub.2]S[O.sub.4].

Ultraviolet (UV) resonance Raman spectroscopy and molecular dynamic simulations are used for examining the change in the environment of the tryptophan (Trp) on ligand binding. The studies on the microscopic role of water molecules in Gal-1 binding to its specific carbohydrate ligands have helped in understanding of the physicochemical properties of Gal-1-saccharide interactions.

A new ethanol sensor as well as a new polymerized crystalline colloidal array (PCCA) pH is developed that can be used in high ionic strength solution. Polymerized hydroxyethyl methacrylate (HEMA) hydrogels, which are highly responsive to ethanol, are used and carboxyl groups are incorporated within the HEMA hydrogel for use in pH sensing.

A study was conducted to examine a Am[III.sub.3] frequencies of polyalanine 21-residue peptide known as AP and also calculate its free energy. The findings provide insight into the [alpha]-helix peptide folding energy landscape which accurately simulates the first experimentally measured [alpha]-helix melting energy landscape.

The UV resonance Raman spectroscopy (UVRRS) at 194 and 204 nm excitation is used to examine the backbone conformation of a 13-residue polypeptide ([gp41.sub.659-671]) that has been shown by NMR to predominantly fold into a [3.sub.10]-helix. The folded and unfolded populations do not change significantly as the temperature is increased from 1 to 60 degree Celsius, suggesting a unique energy landscape where the folded and unfolded conformations are essentially degenerate in energy and exhibit identical temperature dependences.

Trp-cage, a synthetic 20 residue polypeptide, is proposed to be an ultrafast folding synthetic miniprotein, which utilizes tertiary contacts to define its native conformation. UV resonance Raman spectroscopy (UVRS) is utilized with 204 and 229 nm excitation to follow its thermal melting.

The stimulated hydrogel volume transitions of a material are modeled, which binds Pb(super 2+) and is used as a photonic crystal chemical sensing material. This material consists of a polymerized crystalline colloidal array (PCCA) hydrogel, which contains a crown ether molecular recognition group.

Water H-bonding is directly examined to the backbone of alpha-helical peptides by comparing 204 nm UV Raman (UVR) spectra of an alpha-helical peptide between aqueous solution and the dehydrated solid state. Results reveal that H-bonding water sheath occurs around a polyalanine alpha-helical peptide.

An examination of the 204-nm UV Raman spectra of the peptide XAO which is identical to the spectra of small peptides such as ala5 and to the large 21-residue predominantly Ala peptide is presented. The non-alpha-helical conformations of these peptides are dominantly polyproline II (PPII).