We report the use of infrared (IR) microspectroscopy for the analysis of fingerprint residues. The advantage of using an IR microscope lies in the ability to visualize and obtain spectra of individual particles and droplets that make up fingerprint ridge deposits at a spatial resolution of approximately 10 microm. Our initial results suggest that infrared microspectroscopy in reflection-absorpt...

We have obtained room-temperature transient infrared difference spectra of the M412 photoproduct of bacteriorhodopsin (bR) by using a "rapid-sweep" Fourier-transform infrared (FT-IR) technique that permits the collection of an entire spectrum (extending from 1000 to 2000 cm-1 with 8-cm-1 resolution) in 5 ms. These spectra exhibit less than 10(-4) absorbance unit of noise, even utilizing wet sam...

The application of chemometrics to analyze the information of the cis/trans structure of alkenes in infrared spectra (IR) is introduced. For data from the OMNIC IR spectral database, two feature selection methods, Fisher ratios and genetic algorithm-partial least squares (GA-PLS), and two classification methods, support vector machine (SVM) and probabilistic neural network (PNN), have been used...

We report the first observation of infrared (IR) and mass spectra of neutral, aliphatic amino acid clusters: the example presented herein is for (valine)(n), n = 2-5. The clusters are generated in a supersonic expansion and their IR spectra are recorded in various fragment and (valine)(n-1)H(+) (n = 2-5) mass channels. The ions are created by single photon ionization with a VUV laser at 118 nm ...

We present new observations of the infrared (IR) spectrum of neutral methanol and neutral and protonated methanol clusters employing IR plus vacuum ultraviolet (vuv) spectroscopic techniques. The tunable IR light covers the energy ranges of 2500-4500 cm(-1) and 5000-7500 cm(-1). The CH and OH fundamental stretch modes, the OH overtone mode, and combination bands are identified in the vibrationa...

Infrared spectra of solid formamide are reported as a function of temperature. Solid formamide samples were prepared at 30 K and then annealed to higher temperatures (300 K) with infrared transmission spectra being recorded over the entire temperature range. The NH(2) vibrations of the formamide molecule were found to be particularly very sensitive to temperature change. The IR spectra revealed...

Two computer programs were designed for helping in library handling and microbial identification by means of their infrared spectra. The program 'Transform' runs in the IR Data Manager environment and produces ASCII files containing transformed data from infrared absorbance spectra. The program 'WinSpectra' is written in Visual Basic v. 3.0. It imports the ASCII files created with 'Transform', ...

The aim of this study is ultraviolet and infrared spectral characterization of eight new xanthine derivatives. Spectral analysis was performed using an Agilent 8453 Series spectrophotometer and a Tensor 27 Optics FT-IR spectrophotometer. The UV and IR spectra for xanthine derivatives were obtained and in addition, the wavelength maxima of absorption bands and characteristics have been established.

BACKGROUND Fourier-transform infrared (FT-IR) spectrometry has been used to measure small molecules in plasma. We wished to extend this use to measurement of plasma proteins. METHODS We analyzed plasma proteins, glucose, lactate, and urea in 49 blood samples from 35 healthy subjects and 14 patients. For determining the concentration of each biomolecule, the method used the following steps: (a...

A high-throughput screening system for Citrus lines were established with higher sugar and acid contents using Fourier transform infrared (FT-IR) spectroscopy in combination with multivariate analysis. FT-IR spectra confirmed typical spectral differences between the frequency regions of 950-1100 cm(-1), 1300-1500 cm(-1), and 1500-1700 cm(-1). Principal component analysis (PCA) and subsequent pa...