Electrical Impedance Spectroscopy System Research Articles

Viscoelastic Properties of Zona Pellucida of Oocytes Characterized by Transient Electrical Impedance Spectroscopy.

The success rate in vitro fertilization is significantly linked to the quality of the oocytes. The oocyte's membrane is encapsulated by a shell of gelatinous extracellular matrix, called zona pellucida, which undergoes dynamic changes throughout the reproduction cycle. During the window of highest fertility, the zona pellucida exhibits a softening phase, while it remains rigid during oocyte maturation and again after fertilization. These variations in mechanical properties facilitate or inhibit sperm penetration. Since successful fertilization considerably depends on the state of the zona pellucida, monitoring of the hardening process of the zona pellucida is vital. In this study, we scrutinized two distinct genetic mouse models, namely, fetuin-B wild-type and fetuin-B/ovastacin double deficient with normal and super-soft zona pellucida, respectively. We evaluated the hardening with the help of a microfluidic aspiration-assisted electrical impedance spectroscopy system. An oocyte was trapped by a microhole connected to a microfluidic channel by applying suction pressure. Transient electrical impedance spectra were taken by microelectrodes surrounding the microhole. The time-depending recovery of zona pellucida deflections to equilibrium was used to calculate the Young's modulus and, for the first time, absolute viscosity values. The values were obtained by fitting the curves with an equivalent mechanical circuit consisting of a network of dashpots and springs. The observer-independent electrical readout in combination with a fitting algorithm for the calculation of the viscoelastic properties demonstrates a step toward a more user-friendly and easy-to-use tool for the characterizing and better understanding of the rheological properties of oocytes.

Microfluidic aspiration-assisted electrical impedance spectroscopy system is a reliable tool for the characterization of oocyte hardening

The fertilization rate in assisted reproduction depends significantly on the quality of the oocyte, especially on the hardening of the zona pellucida, which is a gelatinous layer of extracellular matrix surrounding the oocyte. Current reproduction techniques use elaborated and frequent manual manipulation steps, which are expensive, non-standardized, and observer dependent. However, a technically simple to perform, reliable and robust, indisputable and observer independent method is needed to characterize the biophysical properties of the oocyte, especially the hardening state of the zona pellucida. Therefore, a microfluidic-based cell trap technique is proposed, which offers a simple oocyte handling through hydrodynamic trapping. The zona pellucida aspiration at an aperture was measured observer-independently by electrical impedance spectroscopy for the first time. Impedance spectra were fitted by an appropriate equivalent electrical circuit model. A numerical in combination with an analytical model correlated the impedance changes with the aspiration length changes, from which Young’s modulus of the zona pellucida was calculated. As a proof-of-concept, the setup was applied to three different genetic mouse oocyte models owing a super soft, a normal and a stiff zona pellucida structure, respectively. The presented measurement technique can either be used for human and animal reproductive medicine to assist artificial fertilization, for the development of contraceptives using the zona pellucida as a barrier or, in general, for all kinds of characterization of rheological properties of single cells.

Portable RDFT-Based EIS System Design With a Low-Complexity Impedance Calculation

This paper presents a novel low-complexity impedance calculation based on a compact recursive discrete Fourier transform (RDFT) for electrical impedance spectroscopy (EIS) system design. Compared to a traditional fast Fourier transform, an arbitrary-length RDFT is not limited by the power-of-two transform length. By choosing a suitable integer ratio of the desired frequency/frequency resolution, the spectrum leakage can be significantly reduced by 4-Hz resolution per bin, which enables a lower magnitude relative error (MRE) and a phase absolute error (PAE) in impedance calculations. Here, the practical measurement results show that the maximum MRE and PAE are below 0.1% and 0.5°, respectively, making this approach superior to previously reported ones. Compared with the state-of-the-art Goertzel filter-based EIS system, the proposed method provides more frequency bins (+43.75%) within the same frequency band, and the operations in terms of square root, division, and arctangent are drastically reduced by 50%, 33%, and 50%, respectively. In addition, the proposed system only costs $474 USD and can serve as a suitable solution for various EIS applications in the future.

UV Irradiation of Nevi: Impact on Performance of Electrical Impedance Spectroscopy and a Convolution Neural Network.

UV irradiation of nevi induces transient melanocytic activation with dermoscopic and histological changes. We investigated whether UV irradiation of nevi may influence electrical impedance spectroscopy (EIS) or convolution neural networks (CNN). Prospective, controlled trial in 50 patients undergoing phototherapy (selective UV phototherapy (SUP), UVA1, SUP/UVA1, or PUVA). EIS (Nevisense, SciBase AB) and CNN scores (Moleanalyzer-Pro, FotoFinder Systems) of nevi were assessed before (V1) and after UV irradiation (V2). One nevus (nevusirr) was exposed to UV light, another UV-shielded (nevusnon-irr). There were no significant differences in EIS scores of nevusirr before (2.99 [2.51-3.47]) and after irradiation (3.32 [2.86-3.78]; P = 0.163), which was on average 13.28 (range 4-47) days later. Similarly, UV-shielded nevusnon-irr did not show significant changes of EIS scores (V1: 2.65 [2.19-3.11]), V2: 2.92 [2.50-3.34]; P = 0.094). Subgroup analysis by irradiation revealed a significant increase of EIS scores of nevusirr (V1: 2.69 [2.21-3.16], V2: 3.23 [2.72-3.73]; P = 0.044) and nevusnon-irr (V1: 2.57 [2.07-3.07], V2: 3.03 [2.48-3.57]; P = 0.033) for patients receiving SUP. In contrast, CNN scores of nevusirr (P = 0.995) and nevusnon-irr (P = 0.352) showed no significant differences before and after phototherapy. For the tested EIS system increased EIS scores were found in nevi exposed to SUP. In contrast, CNN results were more robust against UV exposure.

On-Chip Sinusoidal Signal Generators for Electrical Impedance Spectroscopy: Methodological Review.

This paper reviews architectures and circuit implementations of on-chip sinusoidal signal generators (SSGs) for electrical impedance spectroscopy (EIS) applications. In recent years, there have been increasing interests in on-chip EIS systems, which measure a target material's impedance spectrum over a frequency range. The on-chip implementation allows EIS systems to have low power and small form factor, enabling various biomedical applications. One of the key building blocks of on-chip EIS systems is on-chip SSG, which determines the frequency range and the analysis precision of the whole EIS system. On-chip SSGs are generally required to have high linearity, wide frequency range, and high power and area efficiency. They are typically composed of three stages in general: waveform generation, linearity enhancement, and current injection. First, a sinusoidal waveform should be generated in SSGs. The generated waveform's frequency should be accurately adjustable over a wide range. The firstly generated waveform may not be perfectly linear, including unwanted harmonics. In the following linearity-enhancement step, these harmonics are attenuated by using filters typically. As the linearity of the waveform is improved, the precision of the EIS system gets ensured. Lastly, the filtered voltage waveform is now converted to a current by a current driver. Then, the current sinusoidal signal is injected into the target impedance. This review discusses the principles, advantages, and disadvantages of various techniques applied to each step in state-of-the-art on-chip SSGs. In addition, state-of-the-art designs are compared and summarized.

Electrical Impedance Spectroscopy Improves Skin Cancer Detection and Reduces the Number of Biopsies

There has recently been an increased interest in the use of novel automated technologies for the early detection of skin malignancies. We performed a retrospective analysis of the clinical effectiveness of electrical impedance spectroscopy (EIS) in detecting malignancies in an everyday clinical setting. After a thorough visual examination and dermoscopy, 909 abnormal lesions suspicious for malignancy were detected in 481 patients who presented in a private dermatology practice between 2015 and 2017 and evaluated with the EIS system. The histopathological results of the excised lesions were compared to the Neviscore, the output of the device. In total, 443 lesions (49%) received a negative Neviscore and were thus benign. On the other hand, 466 lesions received a positive Neviscore, indicating aberrations of the physiological cell structure. Of the 909 lesions, 45% were excised after visual and EIS examination. Of the excised lesions, 16% were diagnosed histopathologically as malignant. The EIS detected melanomas with 100% accuracy. The number needed to excise decreased from 17.5 to 7.8. The predictive value for a negative Neviscore was 98.9% (true negative results). EIS was found to be a valuable adjunct support tool when making clinical assessments of potentially malignant lesions.

A Rapid Approach to Measure Extracted Chlorophyll-a from Lettuce Leaves using Electrical Impedance Spectroscopy

Chlorophyll-a is a highly measured metric in water quality and plant health monitoring. Current laboratory-based methods exploit spectroscopic techniques and require expensive instrumentation like spectrophotometer or fluorometer. In this work, a rapid approach has been proposed using electrical impedance spectroscopy (EIS) to measure chlorophyll-a that is extracted from lettuce leaves into 95% (v/v) ethanol. Multiple readings of 70 differently concentrated samples were taken, and the corresponding impedances were measured using the proposed EIS system by varying frequency from 1.5 to 7.5 kHz. Pearson coefficient, variance inflation factor (VIF), and backward elimination were used to identify the significant component of the frequency. Finally, a multiple linear regression model with 11 features in the range of 2.3 kHz to 4.7 kHz was chosen based on the lowest root mean square error (RMSE) and mean absolute error (MAE). The results show high index of positive determination of chlorophyll-a with the coefficient of determination being 0.932, RMSE of 1.05 μgL-1, and MAE of 0.904 μgL-1.

Retrospective evaluation of the performance of the electrical impedance spectroscopy system Nevisense in detecting keratinocyte cancers.

Keratinocyte cancers, also referred to as non-melanoma skin cancers (NMSCs), are one of the most common malignant skin tumors. We performed a retrospective analysis of lesions from patients of a private dermatology practice to evaluate the use of electrical impedance spectroscopy (EIS) in detecting keratinocyte malignancies. The aim of the study is to assess the accuracy of the technique and to rate its use as supportive tool in NMSC diagnosis. The period evaluated ranges from September 2015 to November 2019. In total, 1712 lesions from 951 patients were included. All lesions suspicious for malignancy were gauged with the Nevisense device. Excised lesions were sent in for histopathological classification, and the results were compared to the Nevisense score. A total of 767 lesions (44.8%) received a negative score (0-3) from the Nevisense system and 945 lesions (55.2%) a positive score (4-10). The combination of the dermatologist's visual assessment plus the technical determined Neviscore resulted in the excision of 52.5% of all 1712 suspicious lesions whereof 15% were found to be malignant. The sensitivity of Nevisense was 98.4% for NMSC detection. Electrical impedance spectroscopy was found to be a valuable adjunct support tool in clinical decisions for cases with suspicion for NMSC.

Development of a noise elimination electrical impedance spectroscopy (neEIS) system for single cell identification

We propose a noise elimination electrical impedance spectroscopy (neEIS) system for single cell identification whose characteristics are cell-free clamp structure and cell-position independent calibration. The function of the cell-free clamp structure is to enable a single cell to be freely located into neEIS system. The cell-position independent calibration consists of three steps; impedance measurement, electrode cell constant calculation, and single cell dielectric properties estimation. The cell-position independent calibration enables elimination the influence of noise associated with ions as well as electrical double layer during the measurement process. We demonstrate an application of neEIS system to discriminate three types of MRC-5 human lung fibroblasts; wild type (WT), GFP-fused histone (HT) modification, and GFP transfected (GFPT) MRC-5 cells suspended in a sucrose medium. To further evaluate the neEIS system, we simulated the electrical potential distribution and root means square error of single cell dielectric properties numerically. As a result, we obtained electric potential distribution which clearly characterized the internal change of single cell components. Moreover, we determined that the neEIS system is capable of accurate single cell identification after noises elimination with less than 1.05% average root means square error. Taken together, these results demonstrate that the proposed neEIS system has the potential to improve the performance of biosensors. Thus, this study will bring a new insight into the development of a biosensor system for high accuracy single cell identification as well as inspire the development of a diagnostic device for early fetal lung diseases based on the neEIS system.

Design of using chamber system based on electrical impedance spectroscopy (EIS) to measure epithelial tissue

This work aims to propose a Ussing chamber system based on electrical impedance spectroscopy (EIS) for measuring impedance in epithelial tissues. The proposed method is composed of two functional parts: Ussing chambers (UC) where the tissue under test is located, and the other is a homemade electrical impedance spectroscopy system. The impedance spectroscopy system architecture uses a sine wave generated by a direct digital synthesizer (DDS) with a frequency range from 1 Hz to 102 kHz, a current source in Howland configuration, and an instrumentation stage that allows applying the four electrodes configuration. The designed system was tested with Eleutherodactylus johnstonei adult frog Epithelial tissue, as well as Cole-Cole models, Real and imaginary, and measured impedances were used to find the transfer function parameters employing a genetic algorithm.

Design of Reconfigurable Time-to-Digital Converter Based on Cascaded Time Interpolators for Electrical Impedance Spectroscopy.

This paper presents a reconfigurable time-to-digital converter (TDC) used to quantize the phase of the impedance in electrical impedance spectroscopy (EIS). The TDC in the EIS system must handle a wide input-time range for analysis in the low-frequency range and have a high resolution for analysis in the high-frequency range. The proposed TDC adopts a coarse counter to support a wide input-time range and cascaded time interpolators to improve the time resolution in the high-frequency analysis without increasing the counting clock speed. When the same large interpolation factor is adopted, the cascaded time interpolators have shorter measurement time and smaller chip area than a single-stage time interpolator. A reconfigurable time interpolation factor is adopted to maintain the phase resolution with reasonable measurement time. The fabricated TDC has a peak-to-peak phase error of less than 0.72° over the input frequency range from 1 kHz to 512 kHz and the phase error of less than 2.70° when the range is extended to 2.048 MHz, which demonstrates a competitive performance when compared with previously reported designs.

Evaluation of electrical characteristics of biological tissue with electrical impedance spectroscopy.

The electrical characteristics of biological tissue is evaluated by establishing an electrical equivalent circuit with electrical impedance spectroscopy. The least squares method is used to realize electrical equivalent circuit fitting by using the developed portable electrical impedance spectroscopy system. The EIS system is used to obtain the impedance spectrum data of the measured biological tissue. In the experiment, the impedance spectrum data of eggs under different heating time were measured, and the established equivalent circuit model of eggs was fitted by nonlinear least squares fitting algorithm. Moreover, the electrical characteristics of the biological tissue are also revealed by numerical simulation with HANAI model. The experimental and simulation results show that the extracted equivalent electrical parameters can clearly characterize the variation of the internal change of components of biological tissues.

Bio-impedance and circuit parameters: An analysis for tracking fruit ripening

The evaluation of fruit quality from the field to the table, through its storage, handling and transport has become of paramount importance to meet production and consumers demands. For this purpose, fast, reliable and low-cost non-destructive techniques are highly desirable, to avoid food waste and allow a real-time decision making. Among non-destructive techniques, Electrical Impedance Spectroscopy (EIS) has shown great potential due to the possibility to correlate the physio-chemical evolution of the fruit to changes of electrical parameters. In this paper, the effect of ageing on apples and bananas during 13 d at room temperature was studied using a microcontroller-based EIS system, in a frequency range from 100 Hz to 85 kHz.The bio-impedance changes were evaluated over time and the influence of the applied frequencies on its variation was investigated. Data were fitted with a proposed equivalent circuit, modelling both the interaction between the fruit and the sensor and the flow of current in the samples tissues. To validate the results, the circuit parameter changes were physiologically explained and the fitting compared with models found in literature. The results highlighted the potential of this non-destructive technique for monitoring the ripening and senescence of fruit, obtaining a good correlation of the impedance evolution with the low frequency points. The model fitting resulted in a Root Mean Squared Error (RMSE), for apples (376.5 Ω - 2.66%) and bananas (110.8 Ω - 2.82%), was comparable or better than best literature models. Finally, changes of circuit component values over time was explained for the electrode-fruit interaction and for the current flow in the plant tissues, giving a better insight of fruit ripening and senescence.

User-friendly Interface for Electrical Cell-substrate Impedance Spectroscopy System

User-friendly Interface for Electrical Cell-substrate Impedance Spectroscopy System

Design and development of microcontroller based instrumentation for studying complex bioelectrical impedance of fruits using electrical impedance spectroscopy

AbstractElectrical impedance spectroscopy (EIS) is an electrical impedance technique to characterize the fruits and vegetables in terms of their frequency dependent bioimpedance profile. Standalone, portable, and low‐cost instrumentation is always preferred for conducting EIS procedures. This article reports the studies on the design and development of a Microcontroller based portable impedance measurement system to conduct the EIS studies on the fruits during ripening and storage. The proposed laboratory based EIS system is developed with a Microcontroller ATmega16, a Direct Digital Synthesizers based constant current source AD5930, a current to voltage converter, a low pass filter, and a DSO. To test and evaluate the developed system, the cucumber impedance is studied under the storage condition using EIS to characterize the cucumber freshness from the electrical impedance data. The real parts, imaginary parts of the cucumber impedance are calculated and the Nyquist diagrams are analyzed to study the equivalent circuit analysis. The developed system is compared with a standard impedance analyzer and it is observed that the results obtained from the developed system closely match with the data measured by the commercial impedance analyzer. The developed system is also found suitable for EIS studies of fruits, vegetables, and other biological tissues. The developed system is found low‐cost, fast, and user friendly. PCB based version of the proposed system with display unit will be found as a portable, standalone, and EIS system suitable for outdoor measurement in agricultural‐field applications.Practical applicationsMicrocontroller based low cost electrical impedance spectroscopy (EIS) has been developed and is studied for EIS based fruit ripening analysis. The system is compared with the standard commercial impedance analyzer and it is found suitable fruit ripening characterization, vegetable freshness detection, and health studies of other biological tissues. The microcontroller based EIS system is found portable, low cost, fast, and user friendly device which can be used in laboratory, cultivation fields, cold storages and shops and markets. The developed system allows nontechnical person to operated and collect the data from fruit and vegetable samples. The system acquired data significantly correlate the bioimpedance variation with the ripening states which can be potentially utilized to study the fruit ripening noninvasively at low cost. Hence the product‐form of the developed devise could even be operated by field persons, farmers, and other common men to evaluate the fruit ripening and vegetable freshness.

Investigating Sterol and Redox Regulation of the Ion Channel Activity of CLIC1 Using Tethered Bilayer Membranes.

The Chloride Intracellular Ion Channel (CLIC) family consists of six conserved proteins in humans. These are a group of enigmatic proteins, which adopt both a soluble and membrane bound form. CLIC1 was found to be a metamorphic protein, where under specific environmental triggers it adopts more than one stable reversible soluble structural conformation. CLIC1 was found to spontaneously insert into cell membranes and form chloride ion channels. However, factors that control the structural transition of CLIC1 from being an aqueous soluble protein into a membrane bound protein have yet to be adequately described. Using tethered bilayer lipid membranes and electrical impedance spectroscopy system, herein we demonstrate that CLIC1 ion channel activity is dependent on the type and concentration of sterols in bilayer membranes. These findings suggest that membrane sterols play an essential role in CLIC1’s acrobatic switching from a globular soluble form to an integral membrane form, promoting greater ion channel conductance in membranes. What remains unclear is the precise nature of this regulation involving membrane sterols and ultimately determining CLIC1’s membrane structure and function as an ion channel. Furthermore, our impedance spectroscopy results obtained using CLIC1 mutants, suggest that the residue Cys24 is not essential for CLIC1’s ion channel function. However Cys24 does appear important for optimal ion channel activity. We also observe differences in conductance between CLIC1 reduced and oxidized forms when added to our tethered membranes. Therefore, we conclude that both membrane sterols and redox play a role in the ion channel activity of CLIC1.

Noninvasive Assessment of an Engineered Bioactive Graft in Myocardial Infarction: Impact on Cardiac Function and Scar Healing.

Cardiac tissue engineering, which combines cells and biomaterials, is promising for limiting the sequelae of myocardial infarction (MI). We assessed myocardial function and scar evolution after implanting an engineered bioactive impedance graft (EBIG) in a swine MI model. The EBIG comprises a scaffold of decellularized human pericardium, green fluorescent protein‐labeled porcine adipose tissue‐derived progenitor cells (pATPCs), and a customized‐design electrical impedance spectroscopy (EIS) monitoring system. Cardiac function was evaluated noninvasively by using magnetic resonance imaging (MRI). Scar healing was evaluated by using the EIS system within the implanted graft. Additionally, infarct size, fibrosis, and inflammation were explored by histopathology. Upon sacrifice 1 month after the intervention, MRI detected a significant improvement in left ventricular ejection fraction (7.5% ± 4.9% vs. 1.4% ± 3.7%; p = .038) and stroke volume (11.5 ± 5.9 ml vs. 3 ± 4.5 ml; p = .019) in EBIG‐treated animals. Noninvasive EIS data analysis showed differences in both impedance magnitude ratio (−0.02 ± 0.04 per day vs. −0.48 ± 0.07 per day; p = .002) and phase angle slope (−0.18° ± 0.24° per day vs. −3.52° ± 0.84° per day; p = .004) in EBIG compared with control animals. Moreover, in EBIG‐treated animals, the infarct size was 48% smaller (3.4% ± 0.6% vs. 6.5% ± 1%; p = .015), less inflammation was found by means of CD25+ lymphocytes (0.65 ± 0.12 vs. 1.26 ± 0.2; p = .006), and a lower collagen I/III ratio was detected (0.49 ± 0.06 vs. 1.66 ± 0.5; p = .019). An EBIG composed of acellular pericardium refilled with pATPCs significantly reduced infarct size and improved cardiac function in a preclinical model of MI. Noninvasive EIS monitoring was useful for tracking differential scar healing in EBIG‐treated animals, which was confirmed by less inflammation and altered collagen deposit. Stem Cells Translational Medicine 2017;6:647–655

Wideband Fully-Programmable Dual-Mode CMOS Analogue Front-End for Electrical Impedance Spectroscopy.

This paper presents a multi-channel dual-mode CMOS analogue front-end (AFE) for electrochemical and bioimpedance analysis. Current-mode and voltage-mode readouts, integrated on the same chip, can provide an adaptable platform to correlate single-cell biosensor studies with large-scale tissue or organ analysis for real-time cancer detection, imaging and characterization. The chip, implemented in a 180-nm CMOS technology, combines two current-readout (CR) channels and four voltage-readout (VR) channels suitable for both bipolar and tetrapolar electrical impedance spectroscopy (EIS) analysis. Each VR channel occupies an area of 0.48 mm, is capable of an operational bandwidth of 8 MHz and a linear gain in the range between −6 dB and 42 dB. The gain of the CR channel can be set to 10 kΩ, 50 kΩ or 100 kΩ and is capable of 80-dB dynamic range, with a very linear response for input currents between 10 nA and 100 A. Each CR channel occupies an area of 0.21 mm. The chip consumes between 530 A and 690 A per channel and operates from a 1.8-V supply. The chip was used to measure the impedance of capacitive interdigitated electrodes in saline solution. Measurements show close matching with results obtained using a commercial impedance analyser. The chip will be part of a fully flexible and configurable fully-integrated dual-mode EIS system for impedance sensors and bioimpedance analysis.

Time-lapse electrical impedance spectroscopy for monitoring the cell cycle of single immobilized S. pombe cells.

As a complement and alternative to optical methods, wide-band electrical impedance spectroscopy (EIS) enables multi-parameter, label-free and real-time detection of cellular and subcellular features. We report on a microfluidics-based system designed to reliably capture single rod-shaped Schizosaccharomyces pombe cells by applying suction through orifices in a channel wall. The system enables subsequent culturing of immobilized cells in an upright position, while dynamic changes in cell-cycle state and morphology were continuously monitored through EIS over a broad frequency range. Besides measuring cell growth, clear impedance signals for nuclear division have been obtained. The EIS system has been characterized with respect to sensitivity and detection limits. The spatial resolution in measuring cell length was 0.25 μm, which corresponds to approximately a 5-min interval of cell growth under standard conditions. The comprehensive impedance data sets were also used to determine the occurrence of nuclear division and cytokinesis. The obtained results have been validated through concurrent confocal imaging and plausibilized through comparison with finite-element modeling data. The possibility to monitor cellular and intracellular features of single S. pombe cells during the cell cycle at high spatiotemporal resolution renders the presented microfluidics-based EIS system a suitable tool for dynamic single-cell investigations.

Pilot study: electrical impedance based tissue classification using support vector machine classifier

Tissue classification using computer aided diagnosis can help automated decision making to aid clinical diagnosis. Classification of breast tissue based on spectral features of impedance loci has frequently been done to classify malignant tissue with further requirement of more complex classification methodologies needed to improve the characterisation. In current study, tissue classification is done using in vivo electrical impedance data of 18 human subjects, from four quadrants of breast, palm, nail, arm, bicep and classified using algorithms involving machine learning methodologies, specifically support vector machines (SVMs) that are supervised learning models. They consist of learning algorithms based on the principal of structural risk minimisation. Two methodologies of SVM have been used in this study: with data binning and data pruning and without data binning and data pruning. Data binning and data pruning have improved the sensitivity of the SVM from 76.76 to 89.23%, but the specificity has decreased from 76.23 to 74.15%. This is a pilot study towards testing the reliability of the developed electrical impedance measuring system and developing a data mining-based decision making system into an electrical impedance spectroscopy system, to help users (physicians) with tissue classification leading to reliable objective decision making.