Detection of Hepatitis a Virus in Drinking Water by Enzyme -Immunoassay Using Ultracentrifugation for Virus Concentration

1985 ◽  
Vol 17 (10) ◽  
pp. 39-41 ◽  
Author(s):  
A. Schnattinger

Ten litres of tapwater were seeded with 200 µl (8×108 HAV particles) of a commercial (Organon Teknika) suspension of hepatitis A virus. Following WALTER and RÜDIGER (1981), the contaminated tapwater was treated with a two-stage technique for concentration of viruses from solutions with low virus titers. The two-stage technique consists of aluminium hydroxideflocculation (200 mg/l Al2(SO4)3. 18 H2O, pH 5,4-5,6) as first stage, the second stage of a lysis of aluminium hydroxidegel with citric acid/sodium citrate-buffer (pH 4,7; 1 ml/l sample), separation of viruses from the lysate by ultracentrifugation and suspension in 1 ml phosphate buffer solution (pH 7,2). A commercial solid phase enzyme-linked immunosorbent assay (ELISA) was used for the detection of HAV. HAV was detecterl in the 10.000:1 concentrates, but not in the seeded 101 samples. Approximately 4×108 of the inoculated 8×108 HAV particles were found in the 1 ml concentrates. The efficiency of detection is about 50%, the virus concentration 5000-fold. Although the percentage loss of HAV in comparison with concentration by means of membrane filtration is similar, the ultracentrifugation method yields a larger sample/concentrate ratio, so that smaller amounts of HAV can be detected more efficiently because of the smaller end-volume.

1978 ◽  
Vol 8 (3) ◽  
pp. 277-282 ◽  
Author(s):  
S A Locarnini ◽  
S M Garland ◽  
N I Lehmann ◽  
R C Pringle ◽  
I D Gust

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of hepatitis A virus in human fecal specimens. Investigations with 88 fecal specimens from 77 patients with suspected viral hepatitis and 8 of their household contacts showed that ELISA was as specific and sensitive as radioimmunoassay and almost as sensitive as immune electron microscopy. The ELISA is quick and simple to perform, does not require sophisticated technical equipment, and can be read with the naked eye, making it suitable for field work and rapid diagnosis.


1979 ◽  
Vol 9 (4) ◽  
pp. 459-465
Author(s):  
S A Locarnini ◽  
A G Coulepis ◽  
A M Stratton ◽  
J Kaldor ◽  
I D Gust

A solid-phase enzyme linked immunosorbent assay was developed for the detection of immunoglobulin M antibody to hepatitis A virus. The system was capable of detecting hepatitis A-specific immunoglobulin M in a single dilution of serum and appears to be a reliable and rapid means of establishing a diagnosis of hepatitis A infection. Specific immunoglobulin M was only detected in patients with serologically confirmed hepatitis A and not in patients with other forms of hepatitis, chronic liver disease, or autoimmune disease. In patients with hepatitis A, specific immunoglobulin M was usually detectable for 6 weeks after the onset of dark urine, and the longest period for which it was present in any patient was 115 days. This enzyme-linked immunosorbent assay is rapid, simple to perform, and does not require complicated equipment. Provided adequate supplies of purified reagents can be obtained, this enzyme-linked immunosorbent assay procedure is likely to simplify hepatitis A serology, because the same antibody-coated plates can be utilized to detect hepatitis A virus, anti-hepatitis A virus, and hepatitis A-specific immunoglobulin M.


Author(s):  
Charles D. Humphrey ◽  
E. H. Cook ◽  
Karen A. McCaustland ◽  
Daniel W. Bradley

Enterically transmitted non-A, non-B hepatitis (ET-NANBH) is a type of hepatitis which is increasingly becoming a significant world health concern. As with hepatitis A virus (HAV), spread is by the fecal-oral mode of transmission. Until recently, the etiologic agent had not been isolated and identified. We have succeeded in the isolation and preliminary characterization of this virus and demonstrating that this agent can cause hepatic disease and seroconversion in experimental primates. Our characterization of this virus was facilitated by immune (IEM) and solid phase immune electron microscopic (SPIEM) methodologies.Many immune electron microscopy methodologies have been used for morphological identification and characterization of viruses. We have previously reported a highly effective solid phase immune electron microscopy procedure which facilitated identification of hepatitis A virus (HAV) in crude cell culture extracts. More recently we have reported utilization of the method for identification of an etiologic agent responsible for (ET-NANBH).


Author(s):  
C.D. Humphrey ◽  
T.L. Cromeans ◽  
E.H. Cook ◽  
D.W. Bradley

There is a variety of methods available for the rapid detection and identification of viruses by electron microscopy as described in several reviews. The predominant techniques are classified as direct electron microscopy (DEM), immune electron microscopy (IEM), liquid phase immune electron microscopy (LPIEM) and solid phase immune electron microscopy (SPIEM). Each technique has inherent strengths and weaknesses. However, in recent years, the most progress for identifying viruses has been realized by the utilization of SPIEM.


1989 ◽  
Vol 21 (3) ◽  
pp. 255-258 ◽  
Author(s):  
Evangélos Biziagos ◽  
Jacques Passagot ◽  
Jean-Marc Crance ◽  
Robert Deloince

The concentration of cell-culture-adapted hepatitis A virus (HAV) from experimentally contaminated distilled, drinking, waste and seawater was performed by using a filter adsorption-elu-tion method in the following conditions: HAV seeded in water was adsorbed at pH 4.0 to two nitrocellulose membranes (1.2 and 0.45 µm porosity for distilled and tap water or 8.0 and 3.0 µm porosity for waste and seawater), then eluted by 3% beef-extract at pH 8.5 and further concentrated by polyethylene glycol 6000 precipitation. Thus, HAV in 5 to 50 liters of seeded waters was concentrated approximately 1,700 to 17,000 fold with greater than 70% recovery of the initial virus added to the samples.


2019 ◽  
Vol 11 (30) ◽  
pp. 3866-3873 ◽  
Author(s):  
R. Karthikeyan ◽  
D. James Nelson ◽  
S. Abraham John

Selective and sensitive determination of one of the purine nucleotides, inosine (INO) using a low cost carbon dot (CD) modified glassy carbon (GC) electrode in 0.2 M phosphate buffer solution (pH 7.2) was demonstrated in this paper.


Surfaces ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 191-204
Author(s):  
Edwin S. D’Souza ◽  
Jamballi G. Manjunatha ◽  
Chenthattil Raril ◽  
Girish Tigari ◽  
Huligerepura J. Arpitha ◽  
...  

A modest, efficient, and sensitive chemically modified electrode was fabricated for sensing curcumin (CRC) through an electrochemically polymerized titan yellow (TY) modified carbon paste electrode (PTYMCPE) in phosphate buffer solution (pH 7.0). Cyclic voltammetry (CV) linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV) approaches were used for CRC detection. PTYMCPE interaction with CRC suggests that the electrode exhibits admirable electrochemical response as compared to bare carbon paste electrode (BCPE). Under the optimized circumstances, a linear response of the electrode was observed for CRC in the concentration range 2 × 10−6 M to 10 × 10−6 M with a limit of detection (LOD) of 10.94 × 10−7 M. Moreover, the effort explains that the PTYMCPE electrode has a hopeful approach for the electrochemical resolution of biologically significant compounds. Additionally, the proposed electrode has demonstrated many advantages such as easy preparation, elevated sensitivity, stability, and enhanced catalytic activity, and can be successfully applied in real sample analysis.


2006 ◽  
Vol 510-511 ◽  
pp. 798-801
Author(s):  
Hyung Suk So ◽  
Hyun Chul Shin ◽  
Beom Suk Kim ◽  
Yeong Seok Yoo

The purpose of this study is to develop a new system to control effective discharge of active substances such as agricultural chemicals. To synthesize a naturally dissolvable polymer; ε-caprolactone and diglycolide were copolymerized with ethylene glycol as an initiator to produce macrodiol. As macrodiol has hydroxyl groups in both ends, they are modified with methacryloyl chloride for photochemical networking. After standard macromonomer produced by this procedure was physically mixed with methylene blue, it was networked with ultra-violet rays to be filmed. This film is naturally dissolvable and hydrolytic. As a result of hydrolytic test with a crosslinked structure of 10 % methylene blue, it decreased by 9 % for seven weeks in 37 °C phosphate buffer solution (pH = 7). Thus, we verified that active substance can be discharged from a crosslinked structure for a long time at a constant rate under room temperature.


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