Ultrasensitive detection of streptomycin using flow injection analysis-electrochemical quartz crystal nanobalance (FIA-EQCN) biosensor.

This work presents the development of an ultrasensitive biosensor for detection of streptomycin residues in milk samples using flow injection analysis-electrochemical quartz crystal nanobalance (FIA-EQCN) technique. Monoclonal antibody specific to streptomycin was immobilized on to the thiol modified gold quartz crystal surface. A broad dynamic range (0.3-300 ng/mL) was obtained for streptomycin with a good linearity in the range 0.3-10 ng/mL for PBS and 0.3-50 ng/mL for milk. The correlation coefficient (R(2)) of the biosensor was found to be 0.994 and 0.997 for PBS and milk respectively. Excellent recoveries were obtained from the streptomycin spiked milk samples in the range 98-99.33%, which shows the applicability of the developed biosensor in milk. The reproducibility of the developed biosensor was found satisfactory with % RSD (n=5) 0.351. A good co-relation was observed between the streptomycin recoveries measured through the developed biosensor and the commercial ELISA kit. The analytical figures of merit of the developed biosensor confirm that the developed FIA-EQCN biosensor could be very effective for low-level detection of streptomycin in milk samples.

Pretreatment-free immunochromatographic assay for the detection of streptomycin and its application to the control of milk and dairy products.

A rapid pretreatment-free immunochromatographic assay was developed for the control of the streptomycin (STR) content in milk and dairy products. The assay is based on the competition between an immobilized STR-protein conjugate and STR in a sample to be tested for the binding to monoclonal anti-STR antibodies conjugated to colloidal gold during the flow of the sample along a membrane strip with immobilized reactants. It is possible to improve the cut-off level of positive and negative samples distinguished by a change in the molar STR to protein ratio in the immobilized conjugate. The cut-off level (500 ng mL(-1)) thus achieved corresponds to the stated MRL of STR in milk and dairy products. For STR concentrations in the range of 16-250 ng mL(-1) its content can be quantitatively measured based on the degree of binding of a colloidal gold label in the test strip zone with the immobilized STR-protein conjugate. The duration of the assay is 10 min. The selected sizes of membrane pores and colloidal gold particles allow the assay to be carried out at room temperature without additional reactants and pretreatment. The applicability of the assay for milk, whole milk, sour clotted milk, and kefir with different fat content (from 0.5% to 6%) was confirmed. The results of quantitative immunochromatographic assay show good correlation with traditional ELISA (r was equal to 0.935 and 0.940 for the series tested).

Enzyme immunoassays for the analysis of streptomycin in milk, serum and water: development and assessment of a polyclonal antiserum and assay procedures using novel streptomycin derivatives.

A polyclonal antiserum to streptomycin was generated in sheep using a streptomycin-bovine serum albumin conjugate as immunogen. Streptomycin was linked to the carrier protein with cyanuric chloride using a new two-step conjugation method. Plate coating antigen conjugates of streptomycin and gelatine were prepared using either cyanuric chloride (homologous bridge) or 1,4-butanediol diglycidyl ether to provide an heterologous complex. The reagents enabled the generation of a specific antiserum with a titre of 1/40,000 and the development of a sensitive ELISA method suitable for the measurement of streptomycin sulfate in milk, serum and water samples. A minimum detection value of 1 ng mL(-1) and a dynamic range of 1 to 200 ng mL(-1) were demonstrated in the three matrices. No detectable cross reactivity with any of the common aminoglycosides was found except the related dihydrostreptomycin which gave a 75% cross reaction value. The details of the preparation of the hapten-protein conjugates, characterisation of the antiserum and assay construction and assessment methods are presented. The introduction of new coupling methods and antibody assessment provide improved basic methodologies necessary for the advancement of immuno-analysis of streptomycin, one of the most widely used antimicrobial substances.

Aminoglycoside detection using a universal ELISA binding procedure onto polystyrene microtiter plates in comparison with HPLC analysis and microbiological agar-diffusion assay.

The use of enzyme-linked immunosorbent assay for the detection of aminoglycosides has been hindered due to low molecular weight compound adsorption to solid phases. Here, we describe an enzyme-linked immunosorbent assay based on the treatment of polystyrene microtiter plates with Alcian blue prepared in acetic acid prior to coating with the antibiotic. Whereas no detection of tobramycin was possible on commercially treated or untreated enzyme-linked immunosorbent assay plates, the Alcian blue treatment permitted detection of 0.025 and 0.05 microg ml(-1) of tobramycin respectively using 0.05 and 0.1% of Alcian blue with a coefficient of variation of 1.85 and 7.69%, respectively. Comparative studies of five tobramycin samples of unknown quantity using enzyme-linked immunosorbent assay and high-performance liquid chromatography gave equivalent results while those done via microbiological agar-diffusion assay were an overestimation of the actual quantity. The use of the Alcian blue pretreatment enzyme-linked immunosorbent assay procedure has permitted, in previous studies, the measure of antibodies against synthetic peptides and phospholipids. Subsequently, our demonstration of the sensitivity and reliability of this method in the quantification of tobramycin strongly suggests that the use of Alcian blue pretreatment in enzyme-linked immunosorbent assay can be applied universally to avert molecule immobilization problems on solid phases.

[Allergic drug reactions in children]. / Reacciones alérgicas a medicamentos en niños.

We present a retrospective study of allergic drug reactions seen in our pediatric allergy consulting room during the last 6 years. During this time, 840 patients were examined for suspected adverse drug reactions. Drug allergy was confirmed in 72 cases (8.5%). Of these cases, 29 (40.2%) were considered to be IgE mediated, or immediate hypersensitivity reactions. We have not found significant differences with regards to age, sex, atopic family history or atopia between patients with IgE mediated reactions compared to patients with allergic drug reactions of different mechanisms or to patients without drug allergies. Sulfonamides, streptomycin, beta-lactam and analgesics were the drugs most frequently involved in immediate type reactions. Among non-immediate reactions, fixed eruption by sulfonamides and contact dermatitis due to Mercurochrome were the most frequent.

[Immunocorrecting properties of antibiotics in secondary immunodeficiency]. / Immunokorrigiruiushchie svoistva antibiotikov v usloviiakh vtorichnogo immunodefitsita.

The study investigated immunocorrecting properties of penicillin G, streptomycin, gentamycin in cyclophosphamide--induced immunodeficiency in mice. It was determined, that antibiotics in sub-bactericidal doses possess pronounced immunocorrecting properties. This effect was observed in both humoral and cell-mediated immune response.

Contact dermatitis to antituberculosis drugs.

The literature has been reviewed for contact dermatitis occurring to antituberculosis agents. Of the 12 known drugs, 6 (isoniazid, rifampicin, ethambutol, para-aminosalicylic acid, streptomycin and kanamycin) have been documented by patch test to cause this type of dermatitis in certain individuals. Cross sensitization has been observed to contribute significantly to the allergic reactions noted from isoniazid, streptomycin, and kanamycin. Hyposensitization has also been discussed in this review.

Anaphylaxis presumed to be caused by beef containing streptomycin.

Most adverse reactions to foods have been blamed on proteins derived from the ingested substance. Reports in the literature document that adverse reactions to foods can be caused by contaminants. The youngster reported here had anaphylaxis on four occasions, likely caused by the presence of streptomycin.

Streptomycin-specific antibody coincident with a developing warm autoantibody.

The presence of an antibody with specificity against streptomycin-sensitized red blood cells in the serum of a patient with tuberculous pericarditis is reported. Hemolysis and significant anemia were absent. The antibody appeared to develop together with an evolving warm autoantibody, but was clearly separable from the latter. The streptomycin-specific antibody was "penicillin-like" by being totally neutralized in the presence of streptomycin. Red blood cells had to be separately sensitized with streptomycin prior to incubation with the antibody. The antibody cross-reacted with neomycin-sensitized cells and was also neutralized by the presence of neomycin. In addition, a possible cross-reactivity of the streptomycin-specific antibody and the warm autoantibody is suggested. The association of a drug-induced antibody and autoimmune antibody of IgG type is most unusual. In our experience, we have encountered only one similar example.

[Effect of streptomycin on experimental indices of immunity and nonspecific protection]. / Vliianie streptomitsina na pokazateli immuniteta i nespetsificheskoi zashchity v éksperimente.

It was found that streptomycin administered to rabbits immunized with adsorbed staphylococcal anatoxin did not induce any decrease in the antitoxic antistaphylococcal immunity or suppress the activity of the nonspecific protection factors. The level of the antistaphyloccal immunity observed in the experiments provided the rabbit resistance to experimental staphylococcal infection and prevented its generalization.

[In vitro diagnosis of penicillin and streptomycin allergy. The specific leukocyte alteration reaction using luminescence microscopy]. / K diagnostike allergii k penitsillinu i streptomitsinu in vitro. Reaktsiia spetsificheskoi al'teratsii leikotsitov a primeneniem liuminestsentnoi mikroskopii.

The method of fluorescent microscopy was used for studying the diagnostic value of the reaction of the leucocyte specific alteration (LSA) in patients with different syndromes of hypersensitivity, allergy in the anamnesis and without hypersensitivity to penicillin and streptomycin. It was found that only markedly positive results of the LSA reaction (independent of the sensibilization type) were of diagnostic value, the results of the reaction being stated in half of the patient with hypersensitivity in the anamnesis and in 3/5 of the patients with allergy. Simultaneous use of other tube immunological or skin tests was recommended for the other patients with lower levels of the positive results of the LSA reaction with a purpose of etiological diagnostics or revealing latent sensibilization before treatment with the antibiotics. The LSA reaction is recommended for practical use in complex with other methods of allergological examination.

[Increased streptomycin sensitivity and its associations with microbial allergy]. / Izuchenie povyshennoi chuvstvitel'nosti k streptomitsinu i sochetanii ee s mikrobnoi allergiei.

Regularities of streptomycin hypersensitivity development and its association with microbial allergy were studied on 75 guinea pigs. A model of retarded allergy was obtained by the animal sensitization with streptomycin in doses of 20 000 gamma per 1 kg of the body weight. Two procedures were used for the animal sensitization, i.e. with the use of the Freund adjuvant or without it. Positive skin-allergic tests to streptomycin (mainly 24-hour) were registered 2 weeks after discontinuation of the sensitization and persisted for the whole observation period (up to 6--8 weeks). The tests for the leucocyte migration were also positive and precipitating antibodies were found in the serum according to the Hoigné method. Simultaneous sensitization with streptomycin and staphylococci resulted in some suppression of the development of retarded hypersensitivity to the microbial antigen. Subsequent sensitization at first with staphylococci and then with streptomycin favoured a mutual increase in the allergic reconstruction to both antigens. The histomorphological studies confirmed the data of the immunoallergological examination.