The purpose of this study was to perform a comparative biochemical analysis between conventional spectrophotometry and Raman spectroscopy, techniques used for diagnoses, on the urine of healthy (CT) and diabetic and hypertensive patients (DM&HBP). Urine from 40 subjects (20 in the CT group and 20 in the DM&HBP group) was examined in a dispersive Raman spectrometer (an 830 nm excitation and a 350 mW power). The mean Raman spectra between both groups showed a significant difference in peaks of glucose; exploratory analysis by principal component analysis (PCA) identified spectral differences between the groups, with higher peaks of glucose and proteins in the DM&HBP group. A partial least squares (PLS) regression model estimated by the Raman data indicated the concentrations of urea, creatinine, glucose, phosphate, and total protein; creatinine and glucose were the biomarkers that presented the best correlation coefficient (r) between the two techniques analyzed (r = 0.68 and r = 0.98, respectively), both with eight latent variables (LVs) and a root mean square error of cross-validation (RMSecv) of 3.6 and 5.1 mmol/L (41 and 92 mg/dL), respectively. Discriminant analysis (PLS-DA) using the entire Raman spectra was able to differentiate the samples of the groups in the study, with a higher accuracy (81.5%) compared to the linear discriminant analysis (LDA) models using the concentration values of the spectrometric analysis (60.0%) and the concentrations predicted by the PLS regression (69.8%). Results indicated that spectral models based on PLS applied to Raman spectra may be used to distinguish subjects with diabetes and blood hypertension from healthy ones in urinalysis aimed at population screening.

Human amniotic membrane (hAM) has a great potential in regenerative medicine as it can be disinfected, preserved, and stored. The present study evaluated a hydrodynamic system that uses ozonated water for disinfecting hAM and assessed possible morphological alterations using histological analysis and scanning electron microscopy (SEM). hAM fragments were experimentally contaminated with Staphylococcus aureus (10³ CFU/mL) and submitted to disinfection processes for 5, 10 and 15 minutes (1.95, 3.9 and 5.85 mg/cm² (O₃), respectively). The results of the water microbiological analysis showed that no microbial growth was detected in all water samples. The hAM surface monitoring with swab method and the analysis of fragment inoculated directly into the culture media revealed that no microbial growth was detected after 10 and 15 minutes. The SEM and histological analysis of hAM revealed that morphological alterations in the epithelium began after 10 minutes 3.9 mg/cm² (O₃) of the disinfection process, and significant changes in the epithelial cells were observed after 15 minutes (5.85 mg/cm² (O₃)). These findings indicates that the structural integrity of hAM was maintained during the process and suggest that the technique is a promising system to disinfect this biological material.

Ethylene oxide and gamma irradiation are two well-established sterilizing processes for surgical materials; however, they present toxicity and high cost, respectively. Ozone Gas, O_3(g), has been used effectively for disinfection and sterilization. Low pressure (LP) can promote water vaporization whenever the vapor pressure drops below the water saturation pressure, which at 20 °C (experimental temperature) is 2337 Pa. The microorganism used to contaminate the surgical needles (SN) was Staphylococcus aureus, a gram-positive bacterium whose cytoplasm is mostly water. Sixty SN samples were divided into six groups of 10: negative control (sterile SN), positive control (experimentally contaminated SN), LP group, two groups associating LP and O_3(g), and O_3(g) alone group. The CFU/mL count demonstrated microbicide efficacy of LP+O_3(g) and O_3(g) groups. This is an innovative protocol for microbial inactivation, mainly because of LP application. In the future, this technique can be evaluated for sterilization of SN and other medical devices.

A dynamic fluid system using ozonated water flowing over the bovine peritoneal membrane was developed. Histological analyses were performed to verify the maximum time of ozone exposure to maintain the viability of the biological material. The results indicate that the biological viability of the peritoneum tissue was impaired after 15 minutes of exposure (5.5 mg O₃ (cm²)⁻¹) to ozonated water in a dynamic condition. Thus, this biological sample can be submitted to the dynamic fluid system with ozonated water for 10 minutes at an applied ozone dose of 3.7 mg O₃ (cm²)⁻¹, without inducing significant changes to the tissue.