scholarly journals Biosensors to Monitor Water Quality Utilizing Insect Odorant-Binding Proteins as Detector Elements

Biosensors ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 62 ◽  
Author(s):  
Spiros D. Dimitratos ◽  
Allison S. Hommel ◽  
Kenneth D. Konrad ◽  
Lauren M. Simpson ◽  
Jessica J. Wu-Woods ◽  
...  

In the developing world, the identification of clean, potable water continues to pose a pervasive challenge, and waterborne diseases due to fecal contamination of water supplies significantly threaten public health. The ability to efficiently monitor local water supplies is key to water safety, yet no low-cost, reliable method exists to detect contamination quickly. We developed an in vitro assay utilizing an odorant-binding protein (OBP), AgamOBP1, from the mosquito, Anopheles gambiae, to test for the presence of a characteristic metabolite, indole, from harmful coliform bacteria. We demonstrated that recombinantly expressed AgamOBP1 binds indole with high sensitivity. Our proof-of-concept assay is fluorescence-based and demonstrates the usefulness of insect OBPs as detector elements in novel biosensors that rapidly detect the presence of bacterial metabolic markers, and thus of coliform bacteria. We further demonstrated that rAgamOBP1 is suitable for use in portable, inexpensive “dipstick” biosensors that improve upon lateral flow technology since insect OBPs are robust, easily obtainable via recombinant expression, and resist detector “fouling.” Moreover, due to their wide diversity and ligand selectivity, insect chemosensory proteins have other biosensor applications for various analytes. The techniques presented here therefore represent platform technologies applicable to various future devices.

2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
J. Anthony Byrne ◽  
Pilar A. Fernandez-Ibañez ◽  
Patrick S. M. Dunlop ◽  
Dheaya M. A. Alrousan ◽  
Jeremy W. J. Hamilton

It is estimated that 884 million people lack access to improved water supplies. Many more are forced to rely on supplies that are microbiologically unsafe, resulting in a higher risk of waterborne diseases, including typhoid, hepatitis, polio, and cholera. Due to poor sanitation and lack of clean drinking water, there are around 4 billion cases of diarrhea each year resulting in 2.2 million deaths, most of these are children under five. While conventional interventions to improve water supplies are effective, there is increasing interest in household-based interventions to produce safe drinking water at an affordable cost for developing regions. Solar disinfection (SODIS) is a simple and low cost technique used to disinfect drinking water, where water is placed in transparent containers and exposed to sunlight for 6 hours. There are a number of parameters which affect the efficacy of SODIS, including the solar irradiance, the quality of the water, and the nature of the contamination. One approach to SODIS enhancement is the use of semiconductor photocatalysis to produce highly reactive species that can destroy organic pollutants and inactivate water pathogens. This paper presents a critical review concerning semiconductor photocatalysis as a potential enhancement technology for solar disinfection of water.


Author(s):  
Rafael R. G. Machado ◽  
Talita Glaser ◽  
Danielle B. Araujo ◽  
Lyvia Lintzmaier Petiz ◽  
Danielle B. L. Oliveira ◽  
...  

AbstractWe are facing an unprecedented global health crisis caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). At this date more than 680 thousand people have died due to coronavirus disease 2019 (COVID-19). Unfortunately, until now no effective treatment to combat the virus and vaccine are available. We performed experiments to test if hypertonic saline solution is able to inhibit virus replication in vitro. Our data shows that 260 mM NaCl (1.5%) inhibits 100% SARS-CoV-2 replication in Vero cells. Furthermore, our results suggest that the virus replication inhibition is due to an intracellular mechanism and not due to the dissociation between spike SARS-CoV-2 protein and its human receptor angiotensin-converting enzyme 2 interaction. NaCl depolarizes the plasma membrane supposedly associated with the inhibition of the SARS-CoV-2 life cycle. This observation could lead to simple, safe and low cost interventions at various stages of COVID-19 treatment, improving the prognosis of infected patients, thereby mitigating the social and economic costs of the pandemic.


2021 ◽  
Vol 9 (2) ◽  
pp. 406
Author(s):  
Nieves Martinez-Peinado ◽  
Nuria Cortes-Serra ◽  
Julian Sherman ◽  
Ana Rodriguez ◽  
Juan M. Bustamante ◽  
...  

Chagas disease, caused by the parasite Trypanosoma cruzi (T. cruzi), affects more than six million people worldwide, with its greatest burden in Latin America. Available treatments present frequent toxicity and variable efficacy at the chronic phase of the infection, when the disease is usually diagnosed. Hence, development of new therapeutic strategies is urgent. Repositioning of licensed drugs stands as an attractive fast-track low-cost approach for the identification of safer and more effective chemotherapies. With this purpose we screened 32 licensed drugs for different indications against T. cruzi. We used a primary in vitro assay of Vero cells infection by T. cruzi. Five drugs showed potent activity rates against it (IC50 < 4 µmol L−1), which were also specific (selectivity index >15) with respect to host cells. T. cruzi inhibitory activity of four of them was confirmed by a secondary anti-parasitic assay based on NIH-3T3 cells. Then, we assessed toxicity to human HepG2 cells and anti-amastigote specific activity of those drugs progressed. Ultimately, atovaquone-proguanil, miltefosine, and verapamil were tested in a mouse model of acute T. cruzi infection. Miltefosine performance in vitro and in vivo encourages further investigating its use against T. cruzi.


2021 ◽  
Vol 51 ◽  
Author(s):  
Janniffer Custódio da Silva ◽  
Luan Dionisio Silva Santos ◽  
Paula Sperotto Alberto Faria ◽  
Fabiano Guimarães Silva ◽  
Aurélio Rubio Neto ◽  
...  

ABSTRACT Endophytic bacteria with multifunctional characteristics can benefit plants through different mechanisms, as well as promoting growth in an efficient, low-cost and ecofriendly way. This study analyzed the potential of the multifunctional endophytic isolate Acinetobacter lwoffii Bac109 in promoting the early in vitro growth of sugarcane seedlings. The Bac109 strain showed potential to solubilize phosphate in a solid medium (solubilization index: 3.73). In addition, the bacterium was an efficient biocontrol agent against the phytopathogenic fungi Rhizoctonia sp., Fusarium oxysporum, Phoma sp. and Bipolaris papendorfii, showing a performance equal to or better than the commercial antifungal hygromycin B. An in vitro assay confirmed the biofilm production, which increased in the presence of sugarcane root extract. Additionally, A. lwoffii Bac109 showed a strong adhesion to the sugarcane roots. The inoculation of this bacterium in micropropagated sugarcane seedlings increased the shoot length (35 %) and regulated the nonphotochemical energy dissipation after 28 days of cultivation. At the end of the experiment, the bacterium showed a great potential for survival, with 5.72 × 107 CFU mL-1 recovered from the substrate, what is crucial for plant interaction. The results showed the potential of the biotechnology application for A. lwoffii Bac109 by evaluating multifunctional traits of plant growth promotion and by specific interactions with sugarcane, which may help to improve micropropagation protocols for this crop.


2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
D Traversi ◽  
C Pignata ◽  
E Anedda ◽  
G Gilli

Abstract Background Biosensor technology can potentially revolutionise the area of air pollution monitoring by providing data on early biological effect induction. Such data can be developed for supplementing routine pollution monitoring, improving exposure estimation, including a potential effect estimation and raising community awareness about air pollution. Especially in consideration of complex biological effect such as mutagenic, genotoxic and other proved effects due to the air mixture exposure. The aim of the study is to propose a short-time biosensor for the mutagenic properties evaluation of air pollution. Methods A simple biosensor was developed using genetically modified microorganisms. A first sampling session was conducted in one of the most air-polluted city of Italy using the biosensor and collecting the data of the usual monitoring system, including PM2.5, PM10, NOx, PAHs and metals concentrations. Results The biosensor is able to answer to polluted air mixture indicating a valuable genotoxic effect. Such effect - expressed in relation to the air sampled volume - is comparable to that recorded by traditional genotoxicity in vitro assay on organic extract of particulate matter. Moreover, a comparison with reference measurements is conducted. Repeatability, reproducibility, stability, limit of detection as the impact of environmental factors on biosensor output have been discussed. Conclusions Due to copious difficulties arising when airborne emissions are sampled, biological assays have been applied only sporadically. Aerosol particles are generally collected on a filter and following extraction procedure and bioassay were performed. Monitoring using the biosensor require low sample quantity, directly colliding with the microorganism, and supply good choice when air genotoxicity are to be determined. Key messages Low-cost biosensors can empower high density monitoring of air pollution. The proposed biosensor is able to evaluate genotoxic properties of the air mixture even if data quality is a major concern for its employment.


1976 ◽  
Vol 15 (05) ◽  
pp. 248-253
Author(s):  
A. K. Basu ◽  
S. K. Guha ◽  
B. N. Tandon ◽  
M. M. Gupta ◽  
M. ML. Rehani

SummaryThe conventional radioisotope scanner has been used as a whole body counter. The background index of the system is 10.9 counts per minute per ml of sodium iodide crystal. The sensitivity and derived sensitivity parameters have been evaluated and found to be suitable for clinical studies. The optimum parameters for a single detector at two positions above the lying subject have been obtained. It has been found that for the case of 131I measurement it is possible to assay a source located at any point in the body with coefficient of variation less than 5%. To add to the versatility, a fixed geometry for in-vitro counting of large samples has been obtained. The retention values obtained by the whole body counter have been found to correlate with those obtained by in-vitro assay of urine and stool after intravenous administration of 51Cr-albumin.


1968 ◽  
Vol 20 (03/04) ◽  
pp. 384-396 ◽  
Author(s):  
G Zbinden ◽  
S Tomlin

SummaryAn in vitro system is described in which adhesion of blood platelets to washed and tannic acid-treated red cells was assayed quantitatively by microscopic observation. ADP, epinephrine and TAME produced a reversible increase in platelet adhesiveness which was antagonized by AMP. With Evans blue, polyanetholsulfonate, phthalanilide NSC 38280, thrombin and heparin at concentrations above 1-4 u/ml the increase was irreversible. The ADP-induced increase in adhesiveness was inhibited by sodium citrate, EDTA, AMP, ATP and N-ethylmaleimide. EDTA, AMP and the SH-blocker N-ethylmaleimide also reduced spontaneous platelet adhesion to red cells. No significant effects were observed with adenosine, phenprocoumon, 5-HT, phthalanilide NSC 57155, various estrogens, progestogens and fatty acids, acetylsalicylic acid and similarly acting agents, hydroxylamine, glucose and KCN. The method may be useful for the screening of thrombogenic and antithrombotic properties of drugs.


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