Steven Suryoprabowo

Development of an Immunochromatographic Strip Test for Rapid Detection of Ciprofloxacin in Milk Samples

A rapid, simple, and sensitive immunochromatographic test strip has been developed for testing residues of ciprofloxacin (CIP). A specific and sensitive monoclonal antibody (mAb) for CIP was generated by immunizing BALB/c mice with well-characterized CIP-Keyhole limpet haemocyanin. Under the optimized conditions, the cut-off limits of test strips for CIP were found to be 5 ng/mL in phosphate-buffered saline and 2.5 ng/mL in milk samples. Each test can be evaluated within 3 min. The cross-reactivities of the CIP test strip to enrofloxacin (ENR), norfloxacin (NOR), nadifloxacin (NDF), danofloxacin (DANO), pefloxacin (PEX), lomefloxacin (LOME), enoxacin (ENO), and sarafloxacin (SAR) were 71.4%, 71.4%, 66%, 50%, 33%, 20%, 12.5%, and 6.25%, respectively. The data indicate that the method is sensitive, specific, and has the advantages of simplicity and speed, therefore, this test strip is a useful screening method for the detection of CIP residues in milk samples.

Antibody for the development of specific immunoassays to detect nadifloxacin in chicken muscles

A convenient and specific competitive enzyme-linked immunosorbent assay (ELISA) for nadifloxacin (NDF) was developed. The modified 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) method was employed to synthesise the artificial antigen of NDF. The indirect competitive ELISA developed to detect NDF has a concentration at 50% inhibition (IC50) of 0.72 ng/mL and a limit of detection of 0.04 ng/mL. This ELISA kit could be used as a screening method to detect and control the illegal content of NDF in food products. In this study, the kit was applied to NDF detection in chicken muscle and produced a satisfactory result with recovery rates from samples spiked with NDF of 92% (10 ng/mL) and 101% (50 ng/mL).

Development of a monoclonal antibody assay and a lateral flow strip test for the detection of paromomycin residues in food matrices

ABSTRACT A monoclonal antibody (MAb) was produced against paromomycin and used in the development of an immunoassay and a lateral flow strip test for the detection of paromomycin residues in food matrices. The MAb had 25.1% cross-reactivity with neomycin, but was insensitive to other aminoglycosides. Tested under optimized conditions in 0.01 M phosphate-buffered saline, the half maximum inhibitory concentration (IC50) of the MAb was 0.61 ng/ml for paromomycin and 2.43 ng/ml for neomycin, with results obtained within 90 min. The mean recoveries from spiked food matrices were within the range of 64.56–105.85% for paromomycin and 54.08–100.55% for neomycin. The strip test results for different food matrices were obtained within 5 min and showed visual detection limits of 2.5–20 ng/ml (µg/kg) for paromomycin and 10–30 ng/ml for neomycin. Therefore, the developed immunoassay and strip test can be used in food analysis for routinely monitoring not only paromomycin but also neomycin residues.

Rapid detection of aldicarb in cucumber with an immunochromatographic test strip

ABSTRACT A rapid, simple, and sensitive immunochromatographic strip test has been developed to detect aldicarb (ALD) in 0.01 M phosphate buffer solution (PBS) (pH 7.4) and cucumber samples. The test was developed with a sensitive monoclonal antibody specific for ALD, generated by immunizing BALB/c mice with a well-characterized ALD – keyhole limpet hemocyanin conjugate, produced in our laboratory. Under the optimized condition, the cut-off limits of test strip for ALD were found to be 25 ng/mL in 0.01 M PBS (pH 7.4) and 100 ng/mL in cucumber samples, and the highest standard relative deviation was 9.05%. Both results were obtained within 5 min. The data indicate that the method is sensitive, rapid, and specific, so this immunochromatographic test strip has utility for the rapid high-throughput screening of the pesticide, especially in food samples.

Rapid and sensitive immunoassays for the detection of lomefloxacin and related drug residues in bovine milk samples

ABSTRACT The misuse and illegal use of fluoroquinolones (FQs) in animal-based food products have drawn considerable attention in several countries. As a result, there has been an increased demand for efficient detection methods of FQs in food products. In this study, we developed an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and immunochromatographic strip device based on a monoclonal antibody against lomefloxacin (LFLX), a second generation FQ. Ic-ELISA had an IC50 value of 0.19 ng/mL with a limit of detection of 0.04 ng/mL in 0.01 M phosphate-buffered saline (PBS). The intra- and inter-assay recovery rates of LFLX in bovine milk samples were 98.02–107.40% and 100.65–107.82%. The immunochromatographic assay of LFLX in PBS and spiked bovine milk samples had visual cutoff values at 1 and 5.0 ng/mL, respectively, with significant cross-reactivity with norfloxacin and enoxacin. The developed ic-ELISA and strip method may assist in the detection of FQs in foods.

Development of an immunochromatographic test strip for the detection of ochratoxin A in red wine

ABSTRACT Humans and animals are exposed to mycotoxins naturally present in foods. Ochratoxin A (OTA), one of the most abundant and toxic mycotoxins, is ubiquitous in nature and harmful to humans and animals. In this study, we developed a rapid, simple, specific, and sensitive lateral-flow immunochromatographic assay for detection of OTA in 0.01 M phosphate-buffered saline solution (PBS) (pH 7.4) and in red wine. We produced sensitive and selective monoclonal antibody against OTA. Under optimized conditions, the cut-off limit of the test strip was 10 ng/mL OTA in 0.01 M PBS (pH 7.4) and in red wine. The results were obtained within 10 min. Therefore, our developed method is useful for the detection of OTA in red wine.

Development of a monoclonal antibody assay and immunochromatographic test strip for the detection of amikacin residues in milk and eggs

ABSTRACT An amikacin-sensitive monoclonal antibody (MAb) assay and immunochromatographic test strip were developed and applied for the detection of amikacin residues in bovine milk and chicken eggs. The immunoassay was specific to amikacin and showed no cross-reactivity with other aminoglycosides. The half maximum inhibitory concentration (IC50) of the assay was 0.65 ng/mL and the results were obtained within 90 min. Recoveries from spiked food matrices were within the range of 73.55–84.61% for bovine milk and 73.70–105.75% for whole egg. The strip test results were obtained within 10 min and showed a visual detection limit of 5.0 ng/mL for both food matrices. These results show that the MAb immunoassay and strip test developed in this study are very specific to amikacin and sufficiently sensitive for detection and routine monitoring of amikacin residues in food.

Preparation of an anti-dexamethasone monoclonal antibody and its use in development of a colloidal gold immunoassay

ABSTRACT A lateral flow colloidal gold (CG) immunoassay strip has been developed for detection of dexamethasone (DEX) residues in milk samples. For this purpose, an anti-DEX monoclonal antibody (McAb), based on a DEX succinic anhydride derivative hapten, was prepared and characterized. The McAb showed a high specificity to DEX, the half inhibitory concentration of the antibody was 0.095 ng/mL, its limit of detection (LOD) was 0.017 ng/mL, and its linear range of detection was 0.034–0.265 ng/mL. The developed CG immunoassay had a visual cut-off value of 0.3 ng/mL in phosphate buffered saline (PBS) and 0.5 ng/mL in milk samples. Each test requires 10 min. Analysis of DEX in milk indicated that the results of strip assay had a strong agreement with indirect competitive enzyme-linked immunosorbent assay. Therefore, the CG immunoassay is a sensitive screening method for semi-quantitative and qualitative detection of DEX residues in milk samples.

Development of an immunochromatographic test strip for the detection of papaverine in pure ginger powder

ABSTRACT A leteral-flow immunochromatographic assay was developed for the detection of papaverine (PAPA) in pure ginger powder samples. We produced a sensitive monoclonal antibody againsts PAPA (anti-PAPA mAb) by immunizing BALB/c mice with a well-characterized PAPA-keyhole limpet hemocyanin conjugate, produced in our laboratory. The coating antigen (PAPA-ovalbumin) and goat anti-mouse IgG antibody were used as the capture reagent in the control line of the test strip. Under optimized conditions, the cut-off limits of the test strip was 1 ng/mL in 0.01 M PBS (pH 7.4) and 5 ng/mL in pure ginger powder. The results were obtained within 5 min. The results revealed that the developed method is a sensitive, rapid, and simple tool for the detection of PAPA in pure ginger powder.

Rapid detection of clonidine and its cross-reactivity with apraclonidine in pig urine using an immunochromatographic test strip

ABSTRACT Clonidine (CLO) preferentially stimulates central α-2-adrenoceptors and causes both desirable and undesirable effects. Undesirable effects include sedation and withdrawal reactions, which occur as a sudden rise in arterial pressure, nervousness, agitation, and increased heart rate. An immunochromatographic test strip was developed for the rapid simultaneous detection of CLO and its cross-reactivity with apraclonidine (ACLO) in pig urine. The antigen CLO-OVA and goat anti-mouse IgG were attached to a nitrocellulose membrane as control line and test line. The cut-off limits of the test strips for CLO and ACLO were found to be 2.5 ng/mL in both 0.01 M PBS (pH 7.4) and pig urine. All the results were obtained within 5 min. The results revealed that the developed method is a sensitive, rapid, and simple tool for the detection of CLO and ACLO.