Optimization of incubation time of protein Tc85 in the construction of biosensor: Is the EIS a good tool?

Electrochemical biosensors for neglected tropical diseases: A review

A group of infectious and parasitic diseases with prevalence in tropical and subtropical regions of the planet, especially in places with difficult access, internal conflicts, poverty, and low visibility from the government and health agencies are classified as neglected tropical diseases. While some well-intentioned isolated groups are making the difference on a global scale, the number of new cases and deaths is still alarming. The development and employment of low-cost, miniaturized, and easy-to-use devices as biosensors could be the key to fast diagnosis in such areas leading to a better treatment to further eradication of such diseases. Therefore, this review contains useful information regarding the development of such devices in the past ten years (2010-2020). Guided by the updated list from the World Health Organization, the work evaluated the new trends in the biosensor field applied to the early detection of neglected tropical diseases, the efficiencies of the devices compared to the traditional techniques, and the applicability on-site for local distribution. So, we focus on Malaria, Chagas, Leishmaniasis, Dengue, Zika, Chikungunya, Schistosomiasis, Leprosy, Human African trypanosomiasis (sleeping sickness), Lymphatic filariasis, and Rabies. Few papers were found concerning such diseases and there is no available commercial device in the market. The works contain information regarding the development of point-of-care devices, but there are only at proof of concepts stage so far. Details of electrode modification and construction of electrochemical biosensors were summarized in Tables. The demand for the eradication of neglected tropical diseases is increasing. The use of biosensors is pivotal for the cause, but appliable devices are scarce. The information present in this review can be useful for further development of biosensors in the hope of helping the world combat these deadly diseases.

Lectin-based biosensors as analytical tools for clinical oncology

The review focus on the use of lectin-based biosensors in the oncology field, and ponders the potentialities of using these devices as analytical tools to monitor the levels of cancer glycobiomarkers in biological fluids, helping in the diagnosis, prognosis and treatment assessment. Several examples of lectin-based biosensors directed for cancer biomarkers are described and discussed, and their potential application in the clinic is considered, taking into account their analytical features, advantages and performance in sample analysis. Technical and practical aspects in the construction process, which are specific for lectin biosensors, are debated, as well as the requirements in sample collection and processing, and biosensor validation. Today's challenges for real implementation of these devices in the clinic are presented, along with the future trends in the field.

Mediator free cholesterol biosensor based on self-assembled monolayer platform

Self-assembled monolayer (SAM) of 4-aminothiophenol (4-ATP) has been investigated for immobilization of bi-enzymes (ChOx and ChEt) towards development of enzyme biosensors for detection of free and total cholesterol. This enzyme immobilized SAM surface has been characterized by scanning electron microscopy and electrochemical measurements. The results of electrochemical response studies reveal fast enzymatic reaction in phosphate buffer saline solution without using any artificial mediator. This may be attributed to the molecular wire type behavior of short 4-ATP molecule that promotes electron transfer between enzyme and the electrode surface due to its conjugated structure. Interference free estimation of free and total cholesterol has been realized at low operating potential of 0.33 V with range of detection as 25 to 400 mg dl(-1), sensitivity of 542.3 nA mM(-1) (for ChOx/4-ATP/Au) and 886.6 nA mM(-1) (for ChEt-ChOx/4-ATP/Au) with a response time of 20 s at pH 7.4.