Novel Hollow Octagonal Core Photonic Crystal Fiber (PCF) based Cholesterol Sensor

Cholesterol, also known as the pulpy fat of human body, may cause the body vulnerable to heart malady by filling blood-vessel with fatty substances. This urges a precise, simple, and effective method of cholesterol detection. Considering this, a novel hollow equilateral-octagon core PCF model has been presented as a cholesterol sensor. The sensor is modeled and simulated using finite element method (FEM). Multiple performance metrics suggests the effectiveness of the proposed sensor model. The relative sensitivity attained for the model is 92.34% at optimum frequency (OF), 3.6THz. Besides, the model shows ultra-lower confinement loss of 3.77×10− 18cm−1 at OF along with standard values for other performance metrics. In addition, the feasible implementation of the model by exercising existing fabrication strategies ensures the practicability of the proposed sensor.

Development of a non-invasive method for skin cholesterol detection: pre-clinical assessment in atherosclerosis screening

Background Establishing a high-accuracy and non-invasive method is essential for evaluating cardiovascular disease. Skin cholesterol is a novel marker for assessing the risk of atherosclerosis and can be used as an independent risk factor of early assessment of atherosclerotic risk. Methods We propose a non-invasive skin cholesterol detection method based on absorption spectroscopy. Detection reagents specifically bind to skin cholesterol and react with indicator to produce colored products, the skin cholesterol content can be obtained through absorption spectrum information on colored products detected by non-invasive technology. Gas chromatography is used to measure cholesterol extracted from the skin to verify the accuracy and reliability of the non-invasive test method. A total of 342 subjects were divided into normal group (n = 115), disease group (n = 110) and risk group (n = 117). All subjects underwent non-invasive skin cholesterol test. The diagnostic accuracy of the measured value was analyzed by receiver-operating characteristic (ROC) curve. Results The proposed method is able to identify porcine skin containing gradient concentration of cholesterol. The values measured by non-invasive detection method were significantly correlated with gas chromatography measured results (r = 0.9074, n = 73, p < 0.001). Bland–Altman bias was − 72.78 ± 20.03 with 95% limits of agreement − 112.05 to − 33.51, falling within the prespecified clinically non-significant range. We further evaluated the method of patients with atherosclerosis and risk population as well as normal group, patients and risk atherosclerosis group exhibited higher skin cholesterol content than normal group (all P < 0.001). The area under the ROC curve for distinguishing Normal/Disease group was 0.8642 (95% confidence interval, 0.8138 to 0.9146), meanwhile, the area under the ROC curve for distinguishing Normal/Risk group was 0.8534 (95% confidence interval, 0.8034 to 0.9034). Conclusions The method demonstrated its capability of detecting different concentration of skin cholesterol. This non-invasive skin cholesterol detection system may potentially be used as a risk assessment tool for atherosclerosis screening, especially for a large population.

Recent Development in Nanomaterial-Based Electrochemical Sensors for Cholesterol Detection

Functional nanomaterials have attracted significant attention in a variety of research fields (in particular, in the healthcare system) because of the easily controllable morphology, their high chemical and environmental stability, biocompatibility, and unique optoelectronic and sensing properties. The sensing properties of nanomaterials can be used to detect biomolecules such as cholesterol. Over the past few decades, remarkable progress has been made in the production of cholesterol biosensors that contain nanomaterials as the key component. In this article, various nanomaterials for the electrochemical sensing of cholesterol were reviewed. Cholesterol biosensors are recognized tools in the clinical diagnosis of cardiovascular diseases (CVDs). The function of nanomaterials in cholesterol biosensors were thoroughly discussed. In this study, different pathways for the sensing of cholesterol with functional nanomaterials were investigated.

High Performance CNTENFET with K/PPy/CNT nanocomposite biosensing layer for Cholesterol Detection

We have reported a high-performance dual gated carbon nanotube enzyme modified field-effect transistor (CNT-ENFET) for cholesterol detection. To improve the device performance, we have used dual-gate design with high κ dielectric as top gate and low κ dielectric as bottom gate and a nanocomposite of potassium doped carbon nanotube with polypyrrole (K/PPy/CNT) as the biosensing membrane. The device exhibited a good sensitivity (~1.0 V/decade), low response time (~1 s), wide dynamic range (0.1 - 25) mM, wide linear range (2-20 mM), low detection limit (0.11 mM), good stability (7 months) and high selectivity (interference ~1.8 %).