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Determination of streptomycin in food products of animal origin by ELISA method

Kucharska U., Leszczyńska J.

Zeszyty Naukowe. Chemia Spożywcza i Biotechnologia / Politechnika Łódzka

2004

Z. 68

5-13

Streptomycin in food products has been determined by the immunoenzymatic ELISA method. It has been found that the R-biopharm kit test have a sufficient sensitivity for the determination of streptomycin present as a contaminant in food. Significantly high levels of streptomycin have been confirmed in the samples of beef and chicken meat, while a slightly lower level is observed in pork. The procedure of streptomycin determination and the sensitivity of the immunoenzymatic method are described and discussed.

Do oznaczania streptomycyny w produktach żywnościowych zastosowano immunoenzymatyczną metodę ELISA. Stwierdzono wystarczającą czułość testów firmy R-biopharm do oznaczania streptomycyny występującej w żywności jako zanieczyszczenie. Podwyższone poziomy streptomycyny stwierdzono w próbkach mięsa wołowego i kurczaków oraz na nieco niższym poziomie w mięsie wieprzowym. Opisano i przedyskutowano sposób postępowania w użyciu immunoenzymatycznych oznaczeń streptomycyny.

Metody immunoenzymatyczne w analizie antybiotyków w produktach żywnościowych

Kucharska U., Masłowska J.

Wiadomości Chemiczne

1998

[Z] 52, 3-4

283--310

Antibiotics constitute a group of chemical compounds which arouse extreme excitement - in some cases great expectations and in others fear, anxiety and dismay. Such a situation is due to the observed effects of their action within the sphere of human life. Dosages of these chemicals may be regarded as indispensable and advantageous during medical treatment or as hazardous when overdosed. Antibiotics and antimicrobiological compounds constitute often toxic residuals id food. Due to a wide use of antibiotics as prophylactic measures in the breeding of animals which are the raw material base for the manufacture of food products, and the use of these compounds as food additives to prolong food stability and its life, there is a search going on to find out methods for determination and analysis of speciation of their trace quantities. A valuable and large group of diagnostic methods with potential possibilities and significance in such analyses consists of immunometric methods [1-7]. Generally, these methods are based on selective reaction of complex formation between antibodies and antigens or haptenes which have developed a specific antibody in vertebrates organisms [1-4, 6]. The results of immunochemical reactions depend on many factors such as the type of sorbent, size of active surface, kind of marker, specificity of the formed bonds directly or indirectly affecting the kinetics and physico-chemistry of the serologic process (precipitation or agglutination), [2-7, 16-18]. The use of immunodiagnosis as a method of food analysis results in a considerable lowering of detection and determination thresholds of many substances [8-15]. Known immunological methods can be successfully used not only for the evaluation of antibodies [2-4, 13-18], hormones [19-23], autoantigens [24], but also for the determination of the nutritious components of food [25-28], proteins [29-43], vitamins [44, 45] as well as toxic bacterial, mycotic and mould residues [48-54], antibiotics [55-61], alkaloids [62, 63] and pesticides [64-70]. These methods can be utilized for analyses of final products as well as intermediates and raw materials, including the assessment of specified technological process [71-79]. Their use makes it possible to lower the detection and determination thresholds of the compound under analysis [80-84, 134-136]. Stored food products give rise to the formation of antibiotics under the influence of present or developing microflora [91-103]. The hitherto used methods for the determination of antibiotics include mainly various chromatographic procedures such as HPLC [101-110], GC [106, 111-115], P&TLC [116, 117], MS [118-123], or enzymatic methods. All these methods have been recognized as sensitive and satisfying the requirements of analysts [124-127]. However, their general utilization is relatively low due to expensive apparatus and equipment required. Therefore, in order to improve the sensitivity of determination and reduce the costs of analyses, in the seventies analysts started to use thin-layer or column chromatography in combination with enzymatic or immunochemical reactions [128-133]. At present, penetrating research is going on in analytics to use widely proteins and not only enzymatic ones [1-7, 13, 16-18]. The properties of specific proteins can be used in analytics as agents which either directly or indirectly from selective complexes with the component of the compound under analysis. To provide good and effective monitoring of such reactions one of the serologic reaction components is marked with isotopic tracer (115J, 3H, 57Co, 14C), fluorochromes (fluorescein isothiocyante, rhodamine B isothiocyante), enzymes (peroxidase, alkaline phosphatase, glucose oxidase, urease) or colloidal gold [1-7, 134-136]. In addition, there is used an avidin-biotic system, with antibodies being marked with biotin and enzymes with avidin. Such an extension of biomolecule application increases the sensitivity of the antibody-antigen reaction by increasing the number of addition sites on biotinylated antibodies. Among the immunometric methods, the highest effectiveness ins shown by immunoenzymatic methods which may have a wide application due to the simplicity of their use. The effectiveness of such an analysis depends on the stage of sample preparation being dependent, in turn, on the immunometric method selected. Then, the processes of sample preparation for analysis are different accordingly. In most cases the sample preparation is based on extraction with organic solvents to remove homogenates of samples under analysis [61]. It is a significant point of any analysis to consider the procedures of speciation examination [137-140]. Thus, the choice of immunometric methods, as those with a high specificity, to that end seems to deserve recommendation. The present paper reports the results of comparison of methods for the determination of antibiotics in food products of animal origin. The multidirectional comparison of properties, characteristics and values of various chromatographic methods: HPLC, GC, P&TLC and GC-MS with various immunometric methods has clearly resulted in the benefit of immunoenzymatic methods. The best results in terms of technical development are obtained by the immunoenzymatic method ELISA [2-4, 7, 15-17, 71-74, 83, 84, 138-140]. This is due not only to its high specificity, detectability, sensitivity, but also to the short time of analysis, possibility of multiple repetitions under the same testing conditions, simple equipment and personnel requirements as well as low costs of determination.