Identification and characterization of skin biomolecules for drug targeting and monitoring by vibrational spectroscopy.

The article discusses the application of vibrational spectroscopy techniques for in vivo identification and characterization of glucose biomolecules monitored in the skin of healthy, prediabetes and diabetes subjects; for molecular characterization of water and proteins in in vivo monitored patch tested inflamed skin of the patients with contact dermatitis; for description of nucleic acids and proteins at the molecular level with progression to malignancy in skin cancerous lesions. The results of the studies show new possibilities to assess activity levels of glucose metabolism in the skin tissue of healthy, prediabetes and diabetes subjects; activity and severity of inflammation; activity of the processes of carcinogenesis with regard to benign, premalignant and malignant transformation. Based on our findings, we suggest that vibrational spectroscopy might be a rapid screening tool with sufficient sensitivity and specificity to identify and characterize skin biomolecules in described diseases for drug targeting and monitoring by the pharmacological community.

Vibrational spectroscopy for molecular characterisation and diagnosis of benign, premalignant and malignant skin tumours.

Understanding the molecular, cellular and tissue changes that occur during skin carcinogenesis is central to cancer research in dermatology. The translational aspects of this field--the development of clinical applications in dermatology from the laboratory findings--aim at improving clinical diagnosis, monitoring and treatment of skin cancer. Vibrational spectroscopy, both infrared (IR) and Raman spectroscopy, would be helpful in achieving those goals, since it has been shown to have potential in characterising and discriminating tumour and dysplastic tissue from normal tissue. Clinically differential diagnosis of skin tumours is often difficult and a histopathologic analysis of skin biopsies remains the standard for diagnostic confirmation. We review and update the literature on the subject, demonstrating that the IR and Raman spectra of skin tissues provide valid and useful diagnostic information about a number of skin tumours. We also include a survey of introduced sampling methods for IR and Raman spectroscopy in dermatology, and additionally describe the differences between microscopic, macroscopic and fibreoptic diagnosis of skin cancer. Although in its early stages, we remain optimistic that vibrational spectroscopy has the potential to be fully accepted as a rapid screening tool with sufficient sensitivity and specificity for non-destructive in vitro, ex vivo and in vivo analyses by the dermatological community. Further progress toward molecular characterisation of skin cancer by vibrational spectroscopy would have important research and clinical benefits in dermatology.

Fiber optic near-infrared Raman spectroscopy for clinical noninvasive determination of water content in diseased skin and assessment of cutaneous edema.

Currently, measuring Raman spectra of tissues of living patients online and in real time, collecting the spectra in a very short measurement time, and allowing diagnosis immediately after the spectrum is recorded from any body region, are specific advantages that fiber optic near-infrared Raman spectroscopy (NIR RS) might represent for in vivo clinical applications in dermatology. We discuss various methodological aspects and state of the art of fiber optic NIR RS in clinical and experimental dermatology to outline its present advantages and disadvantages for measuring skin in vivo, particularly its water content. Fiber optic NIR Fourier transform (FT) RS has been introduced to dermatological diagnostics to obtain information regarding the molecular composition of the skin up to several hundred micrometers below the skin surface in a relatively fast nondestructive manner. This has been especially important for probing for in vivo assessment of cutaneous (intradermal) edema in patients patch test reactions. Fiber optic NIR FT Raman spectrometers still require further technological developments and optimization, extremely accurate water concentration determination and its intensity calculation in skin tissue, and for clinical applications, a reduction of measurement time and their size. Another promising option could be the possibility of applying mobile and compact fiber optic charge-coupled device (CCD)-based equipment in clinical dermatology.