Breast cancer (BC) is a malignant disease with a high prevalence worldwide. The main cause of death is not the primary tumor, but instead the spread of tumor cells to distant sites. The aim of the present study was to examine a new method for the detection of cancer cells in aqueous medium using bioimpedance spectroscopy assisted with magnetic nanoparticles (MNP’s) exposure to a constant magnetic field. The spectroscopic patterns were identified for three breast cancer cell lines. Each BC cell line represents a different pathologic stage: the early stage (MCF-7), invasive phase (MDA-MB-231) and metastasis (SK-BR-3). For this purpose, bioimpedance measurements were carried out at a certain frequency range with the aid of nanoprobes, consisting of magnetic nanoparticles (MNPs) coupled to a monoclonal antibody. The antibody was specific for the predominant cell surface protein for each cell line, which was identified by using RT-qPCR and flow cytometry. Accordingly, EpCAM corresponds to MCF-7, MUC-1 to MDA-MB-231, and HER-2 to SK-BR-3. Despite their low concentrations, BC cells could be detected by impedance spectroscopy. Hence, this methodology should permit the monitoring of circulating tumor cells (CTC) and therefore help to prevent recurrences and metastatic processes during BC treatment.

Motivated by the need of poor and rural Mexico, where the population has limited access to advanced medical technology and services, we have developed a new paradigm for medical diagnostic based on the technology of “Volumetric Electromagnetic Phase Shift Spectroscopy” (VEPS), as an inexpensive partial substitute to medical imaging. VEPS, can detect changes in tissue properties inside the body through non-contact, multi-frequency electromagnetic measurements from the exterior of the body, and thereby provide rapid and inexpensive diagnostics in a way that is amenable for use in economically disadvantaged parts of the world. We describe the technology and report results from a limited pilot study with 46 healthy volunteers and eight patients with CT radiology confirmed brain edema and brain hematoma. Data analysis with a non-parametric statistical Mann-Whitney U test, shows that in the frequency range of from 26 MHz to 39 MHz, VEPS can distinguish non-invasively and without contact, with a statistical significance of p<0.05, between healthy subjects and those with a medical conditions in the brain. In the frequency range of between 153 MHz to 166 MHz it can distinguish with a statistical significance of p<0.05 between subjects with brain edema and those with a hematoma in the brain. A classifier build from measurements in these two frequency ranges can provide instantaneous diagnostic of the medical condition of the brain of a patient, from a single set of measurements. While this is a small-scale pilot study, it illustrates the potential of VEPS to change the paradigm of medical diagnostic of brain injury through a VEPS classifier-based technology. Obviously substantially larger-scale studies are needed to verify and expand on the findings in this small pilot study.

A new gene detection technique that is fast, inexpensive, and easy-to-use is urgently needed in hospitals, clinics, and laboratories without access to expensive equipments. The lack of a practical, minimally invasive, and economical method constitutes the main impediment to the promotion of genetic medicine in developing countries. Radiofrequency scattering parameters are an inexpensive gene sensor potentially capable of noninvasively identifying biological materials. They represent a quantitative value for the electromagnetic reflection/transmission characteristics of certain molecular markers in a given frequency domain. The S21 parameter is the difference between the signal received and that transmitted. The aim of this study is to evaluate the S21 transmittance parameters (magnitude and phase) as an indirect impedance measurement for detecting the label-free complementary deoxyribonucleic acid (cDNA) amplification of the 16S ribosomal subunit gene. S21 values showed differences associated with distinct cDNA concentrations. Hence, this technique could possibly facilitate the design of an inexpensive, label-free, and easy-to-use gene sensor.

Detecting bacteria in samples and differentiating between Gram-negative and Gram-positive species is an important challenge, and the most common method, Gram staining, is very time consuming. The a... Graphical abstract Methodology infographic. Step-by-step schematic representation of the electrical bioimpedance spectroscopy capable of determining and identifying bacteria type in any biological ... METHOD SUMMARY We have developed a novel nonlabeling (or nonstaining) method to detect bacteria and to differentiate between Gram types based on their electrical properties, cell wall structure and...

It is necessary to evaluate the total deoxyribonucleic acid (DNA) concentration in gene expression assays. The existing techniques require equipment that is expensive for many labs in developing countries. Portable and inexpensive equipment is needed for easy and economical DNA quantification. Electrical bioimpedance spectroscopy (EBiS) is a non-invasive and inexpensive technique for examining the electrical properties of biological materials. The aim of this study was to explore a potential correlation between the measurement of total DNA extracted from human samples by UV-Vis spectrophotometry and EBiS. Hence, after quantifying the total DNA extracted from each sample by UV-Vis spectroscopy, EBiS was recorded and a possible correlation between the two measurements was analyzed. Considering the bioimpedance phase parameter at 5.24 MHz, a significant correlation was found with total DNA, especially when the concentration was below 100 ng/μL (Spearman coefficient = 0.82, p<0.005). Additional experiments are warranted to confirm these findings.