Cholesterol biosensors: A review

• Published in: Steroids Vol. 143; pp. 6 - 17
• Main Authors: Narwal, Vinay, Deswal, Ritu, Batra, Bhawna, Kalra, Vijay, Hooda, Ritu, Sharma, Minakshi, Rana, J.S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.03.2019
• Subjects: Biological materials; Biosensing Techniques - methods; Cholesterol; Cholesterol - analysis; Cholesterol - chemistry; Cholesterol biosensors; Cholesterol oxidase; Electrochemistry; Humans; Liquid Crystals - chemistry; Nanomaterials; Nanotechnology; Photochemical Processes; Nanomaterials; Cholesterol oxidase; Cholesterol biosensors; Cholesterol; Biological materials
• ISSN: 0039-128X; 1878-5867
• DOI: 10.1016/j.steroids.2018.12.003

•Serum cholesterol level plays important role in the diagnosis and treatment of various diseases e.g. hypothyroidism, nephrotic syndrome, diabetes and liver diseases.•Cholesterol level upto 200 mg/dL (healthy person), 200–239 mg/dL (borderline high).•Present review summarizes the principle of various biosensing methods for determination of cholesterol. Cholesterol is the most important sterol synthesized by most of the human cells majorly in the liver. It is a necessary constituent of cell membranes, it acts as a precursor for the synthesis of steroid hormones, vitamin D, and bile acids. Cholesterol is transported in plasma primarily in the form of low-density lipoproteins (LDL), the principal route for its removal from tissues to the liver is in high-density lipoproteins (HDL), followed by excretion in the bile. Cholesterol level is less than 200 mg/dL in healthy persons. 200 and 239 mg/dL is considered borderline high and 240 mg/dL and above is considered a biomarker for cardiovascular diseases, heart attack, strokes, peripheral arterial disease, type 2 diabetes and high blood pressure. Several methods are available for detection of cholesterol, among them, most are burdensome, time-consuming, require sample pre-treatment, high-cost instrumental set-up, and experienced personnel to operate. Biosensing approach overcomes these disadvantages, as these are highly specific, fast, easy, cost-effective, and highly sensitive. The review describes the various cholesterol biosensors. Cholesterol biosensors work ideally within 1 to 300 s, in pH range, 7.0–8.6, temperature 25–37 °C and cholesterol concentration range, 0.000025–700 mM, the detection limits being in the range, 0.000002–4 mM, with working potential −0.05 to 0.65 V. These biosensors measured cholesterol level in fruit juices, beverages, sera and urine samples and reused up to 200 times over a period of 15 to 50 days, while stored dry at 4 °C (Table 1). Future perspective for further improvement and commercialization of cholesterol biosensors are discussed.