Determination of lincomycin residues in salmon tissues by gas chromatography with nitrogen-phosphorus detection

Quantitative Analysis of Spectinomycin and Lincomycin in Poultry Eggs by Accelerated Solvent Extraction Coupled with Gas Chromatography Tandem Mass Spectrometry

A method based on accelerated solvent extraction (ASE) coupled with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed for the quantitative analysis of spectinomycin and lincomycin in poultry egg (whole egg, albumen and yolk) samples. In this work, the samples were extracted and purified using an ASE350 instrument and solid-phase extraction (SPE) cartridges, and the parameters of the ASE method were experimentally optimized. The appropriate SPE cartridges were selected, and the conditions for the derivatization reaction were optimized. After derivatization, the poultry egg (whole egg, albumen and yolk) samples were analyzed by GC-MS/MS. This study used blank poultry egg (whole egg, albumen and yolk) samples to evaluate the specificity, sensitivity, linearity, recovery and precision of the method. The linearity (5.6-2000 μg/kg for spectinomycin and 5.9-200 μg/kg for lincomycin), correlation coefficient (≥0.9991), recovery (80.0%-95.7%), precision (relative standard deviations, 1.0%-3.4%), limit of detection (2.3-4.3 μg/kg) and limit of quantification (5.6-9.5 μg/kg) of the method met the requirements for EU parameter verification. Compared with traditional liquid-liquid extraction methods, the proposed method is fast and consumes less reagents, and 24 samples can be processed at a time. Finally, the feasibility of the method was evaluated by testing real samples, and spectinomycin and lincomycin residues in poultry eggs were successfully detected.

Development and validation of LC-MS/MS methods to measure tobramycin and lincomycin in plasma, microdialysis fluid and urine: application to a pilot pharmacokinetic research study

Background

The aim of our work was to develop and validate a hydrophilic interaction liquid chromatography-electrospray ionization-tandem mass spectrometry (HILIC-ESI-MS/MS) methods for the quantification of tobramycin (TMC) and lincomycin (LMC)in plasma, microdialysis fluid and urine.

Methods

Protein precipitation was used to extract TMC and LMC from plasma, while microdialysis fluid and urine sample were diluted prior to instrumental analysis. Mobile phase A consisted of 2 mM ammonium acetate in 10% acetonitrile with 0.2% formic acid (v/v) and mobile phase B consisted of 2 mM ammonium acetate in 90% acetonitrile with 0.2% formic acid (v/v). Gradient separation (80%–10% of mobile phase B) for TMC was done using a SeQuant zic-HILIC analytical guard column. While separation of LMC was performed using gradient elution (100%–40% of mobile phase B) on a SeQuant zic-HILIC analytical column equipped with a SeQuant zic-HILIC guard column. Vancomycin (VCM) was used as an internal standard. A quadratic calibration was obtained over the concentration range for plasma of 0.1–20 mg/L for TMC and 0.05–20 mg/L for LMC, for microdialysis fluid of 0.1–20 mg/L for both TMC and LMC, and 1–100 mg/L for urine for both TMC and LMC.

Results

For TMS and LMC, validation testing for matrix effects, precision and accuracy, specificity and stability were all within acceptance criteria of ±15%.

Conclusions

The methods described here meet validation acceptance criteria and were suitable for application in a pilot pharmacokinetic research study performed in a sheep model.

Anodic Voltammetric Behavior of Lincomycin and its Electroanalytical Determination in Pharmaceutical Dosage form and Urine at Gold Electrode

The anodic voltammetric behavior of an antibiotic drug, lincomycin hydrochloride (LIN) at gold electrode (GE) has been investigated using cyclic and linear sweep voltammetry. The dependence of the current on pH, concentration and scan rate were investigated to optimize the experimental conditions for the determination of lincomycin. The anodic peak was characterized and the process was adsorption-controlled. The number of electrons transferred in the oxidation process was calculated. In the range of 8.0×10−6 to 1.0×10−4 M, the current measured by linear sweep voltammetry presents a good linear property as a function of the concentration of lincomycin with a detection limit of 1.7×10−7 M with good selectivity and sensitivity. The proposed method was successfully applied to lincomycin determination in pharmaceutical dosage form and in urine as a real sample. This method can be employed in clinical analysis, quality control and routine determination of drugs in pharmaceutical formulations.

Comparison of an Enzyme-Linked Immunosorbent Assay with an Immunochromatographic Assay for Detection of Lincomycin in Milk and Honey

An enzyme-linked immunosorbent assay (ELISA) and an immunochromatographic assay were constructed for the detection of lincomycin (LIN) in both milk and honey samples based on the monoclonal antibody named 5F6. The half-maximum inhibition of ELISA was 0.3 ng/mL after optimizing pH and ionic strength conditions; the limit of detection was 0.07 ng/mL. The cross-reactivity with clindamycin was 0.6%. LIN recovery in spiked milk and honey samples ranged from 84.6% to 115.6% with intra-assay coefficient variations of 1.7-25.4% and inter-assay coefficient variations of 2.7-8.9%. The detection limits were estimated as 2.1 µg/L for milk and 2.1 µg/kg for honey samples. The immunochromatographic assay revealed a LIN cut-off value of 10 ng/mL in PBS, 5 ng/mL in milk, and 120 ng/g in honey, and a visual lower detection limit of 2.5 ng/mL, 1 ng/mL and 30 ng/g in PBS, milk and honey, respectively. The immunochromatographic assay is preferred for large-scale practical application for its simpler pretreatment and satisfied sensitivity compared with ELISA assay.

A flow injection chemiluminescence method for the determination of lincomycin in serum using a diperiodato-cuprate (III)-luminol system

In this paper, the novel trivalent copper-periodate complex {K₅[Cu(HIO₆)₂], DPC} has been applied in a luminol-based chemiluminescence (CL) reaction. Coupled with flow injection (FI) technology, the FI-CL method was proposed for the determination of lincomycin hydrochloride. The CL reaction between luminol and DPC occurred in an alkaline medium. The CL intensity could be greatly enhanced by lincomycin hydrochloride. The relative CL intensity was proportional to the concentration of lincomycin hydrochloride in the range of 1 × 10⁻⁸ to 5 × 10⁻⁶ g mL⁻¹ and the detection limit was at the 3.5 × 10⁻⁹ g mL⁻¹ level. The relative standard deviation at 5 × 10⁻⁸ g mL⁻¹ was 1.7% (n = 9). The sensitive method was successfully applied to the direct determination of lincomycin hydrochloride (ng mL⁻¹) in serum. A possible mechanism of the lumonol-DPC CL reaction was discussed by the study of the CL kinetic characteristics and the spectra of CL reaction. The oxidability of DPC was studied by means of its electrochemical response.

Development of a competitive indirect ELISA for the determination of lincomycin in milk, eggs, and honey

Polyclonal antibodies to lincomycin (LIN) were developed in rabbit as a result of immunization with BSA-LIN conjugate. Periodate oxidizing of hapten was the common step of both immunogen synthesis and preparation of conjugated antigens for coating plates (homologous and heterologous). Several ELISA variants on a base of the different antigens immobilized on polystyrene were compared. Heterology of solid-phase antigens was provided with relative hapten clindamycin (CLIN) and ethylene- or hexanediamine as spacer arm between hapten and carrier. The spacer insertion yielded no desirable effect, whereas gelatin-CLIN assay variant showed better test characteristics in comparison with the homologous one, although insignificant (IC(50) was 9.15 vs 18.3 ng mL(-1)). The detection limits of the developed test, being estimated as 0.43 ng mL(-1) (milk) and 0.65 ng mL(-1) (eggs), were sufficient to measure maximum residue levels for LIN in examined matrices. This value for honey was 1.9 ng mL(-1) (1.3 μg kg(-1)). The assay sensitivity was enough to dilute milk, egg, and honey samples by 10-100 times to minimize matrix effect. The examination of matrix effect and simple ways of its overcoming are detailed in the paper. The developed assay showed 111% cross-reactivity with CLIN; therefore, it is suitable for the determination of both lincosamides.

A sensitive and specific enzyme-linked immunosorbent assay for the detection of lincomycin in food samples

BACKGROUND

Lincomycin (LIN) is an antibiotic widely used in veterinary medicine to cure infections caused by Gram-positive pathogens. Although the toxicity of LIN is not serious, it will cause adverse effects in humans, such as pseudomembranous enteritis and bacterial resistance. In this study, for the preparation of a LIN derivative, a novel modification method was adopted. The LIN derivative modified at 2-position with a carboxylic group at the end of the spacer was synthesised and coupled to carrier proteins. A LIN polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA) was developed and characterised.

RESULTS

The ELISA standard curve was constructed with concentrations of 0.1-1000 ng mL(-1). The IC(50) value for nine standard curves was in the range 23.7-29.3 ng mL(-1) and the limit of detection at a signal-to-noise ratio of 3 was 0.15-0.98 ng mL(-1). The cross-reactivity value of the LIN antibody with clindamycin hydrochloride, a homologue of LIN with similar molecular structure, was 18.9%, while less than 0.1% cross-reactivity was found with seven other compounds. For LIN-spiked food samples, the recoveries and relative standard deviation (RSD) were 76.6-117.6% and 1.7-34.6%, respectively.

CONCLUSION

The proposed ELISA can be utilised as a sensitive and specific analytical tool for the detection of LIN in food samples.

Detection of antibiotic resistant bacteria inhabiting the sand of non-recreational marine beach

The present study examined the antibiotic resistance of heterotrophic bacteria, which were isolated from the sand of the beach located in the National Park of the southern Baltic Sea coast. The bacteria demonstrated low levels of antibiotic resistance. These microorganisms were the most resistant to cefaclor and clindamycin and the most sensitive to clarithromycin, doxycycline, gentamycin and oxytetracycline. The majority of bacteria inhabiting the sand of the studied beach were resistant to only one antibiotic out of 18 tested antibiotics in this study. The bacteria inhabiting the middle part of the beach and the dune were more antibiotic resistant than bacteria isolated from the seawater and the shoreline-seawater contact zone. Generally, there was no significant difference in antibiotic resistance between bacteria isolated from the surface and the subsurface sand layers. The bacterial antibiotic resistance level depends on the chemical structure of antibiotics.

High-throughput quantification of lincomycin traces in fermentation broth of genetically modified Streptomyces spp

A new separation and quantification method using ultra-performance liquid chromatography (UPLC) with UV detection was developed for detection of lincomycin traces in fermentation broth of different Streptomyces spp. A similar high-performance liquid chromatography (HPLC) protocol was simultaneously developed for comparison purposes. Both methods were validated and showed a linear range of detector response for quantification of lincomycin in concentration from 3.125 to 1000.0 microgml(-1) with correlation coefficient 0.999 and recoveries ranging from 81.5 to 89.85% with precision < or =5%. Compared with the HPLC, the UPLC method offered high sample throughput and about 10 times lower consumption of solvents. The developed assays were used for determination of lincomycin production in genetically manipulated production strain Streptomyces lincolnensis and for determination of lincomycin production after heterologous expression of lincomycin biosynthetic gene cluster in non-producing strain Streptomyces coelicolor.

Development of a hydrophilic interaction chromatography–mass spectrometry assay for spectinomycin and lincomycin in liquid hog manure supernatant and run-off from cropland

A specific and sensitive analytical method was developed to extract and quantify spectinomycin and lincomycin in liquid hog manure supernatant and simulated rainfall run-off from manure-treated cropland. Sample extracts were prepared using solid-phase extraction (SPE) employing a weak cation-exchange resin (Oasis WCX) for extraction of spectinomycin. An Oasis HLB cartridge was used for extraction of lincomycin. Hydrophilic interaction chromatography (HILIC) was used to obtain the necessary separation of the two antibiotics from interfering compounds and to provide baseline separation. Analytes were detected using atmospheric pressure chemical ionization tandem mass spectrometry. Extraction recoveries were 77% for lincomycin and 84% for spectinomycin in liquid hog manure supernatant, and 89% for lincomycin and 95% for spectinomycin in run-off water. The corresponding limits of quantitation were 6.0 and 0.040 microg l(-1) for spectinomycin and lincomycin, respectively, in liquid hog manure supernatant and 0.2 and 0.008 microg l(-1) for spectinomycin and lincomycin, respectively, in run-off from manure treated cropland. The method is suitable for monitoring the environmental fate and transport of these two antibiotics in both liquid hog manure and agricultural field run-off.

Quantitative analysis of lincomycin in animal tissues and bovine milk by liquid chromatography electrospray ionization tandem mass spectrometry

A sensitive method for determining lincomycin in bovine milk, animal muscles and organs using liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI/MS/MS) is presented. Milk and homogenized animal tissues were extracted with acetonitrile twice after addition of an appropriate amount of clindamycin, a lincosamide analogue as the internal standard. The combined extracts were finally made up to 10 ml with distilled water and partitioned with hexane to remove the animal fats prior to analysis. Analytes in the extracts were separated on a reversed phase C18 column (250 mm x 2.1 mm, 5 microm) using a mobile phase of a 3:7 (v/v) mixture of 0.1% formic acid in acetonitrile and an ammonium formate buffer (ammonium formate:formic acid:acetonitrile:water, 1:5:50:950, v/v/v/v) running at a flow rate of 0.2 ml min(-1). Presence of lincomycin was confirmed by the presence of two characteristic product ions at m/z 126.1 and 359.2 within a defined retention time window from the precursor ion at m/z 407.2, whilst quantification was based on the relative ratio of the sum of the peak areas at m/z 126.1 and 359.2 for lincomycin to that of the internal standard (peaks at m/z 126.1 and 377.2) with reference to the respective ratios of the calibration standards. The validated method that was found to have linear responses in the calibration range from 25 to 3000 microg kg(-1) and satisfactory intra-day and inter-day accuracy (94.4-107.8%) and precision (1.3-7.8%) at concentrations ranging from 100 to 1500 microg kg(-1) has been applied to real samples and matrix spiked samples. It is considered robust and suitable for analysis of lincomycin in milk and animal tissues.

Determination of lincomycin and tylosin residues in honey using solid-phase extraction and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry

An analytical method for the determination of residues of the antibiotic drugs lincomycin and tylosin in honey was developed. The procedure employed a solid-phase extraction for the isolation of lincomycin and tylosin from diluted honey samples. The antibiotic residues were subsequently analyzed by reversed-phase HPLC with atmospheric pressure chemical ionization mass spectrometric detection. Average analyte recoveries for lincomycin and tylosin ranged from 84 to 107% in replicate sets of honey samples fortified with drug concentrations of 0.01, 0.5, and 10 microg/g. The method detection limits were determined to be 0.007 and 0.01 microg/g for lincomycin and tylosin, respectively.