A Rapid Method for the Determination of Whey Protein Denaturation

SummaryA method using low resolution NMR spectroscopy is described for investigating whey protein thermal denaturation. The method is based on measuring at 20 °C changes in water proton transverse (T2) relaxation parameter following the denaturing treatment. This parameter is shown to be sensitive to protein denaturation and not to other phenomena such as gelation. Examples are given for the qualitative study of protein thermal denaturation in whey protein concentratc, β-lactoglobulin, α-lactalbumin, bovine serum albumin and immunoglobulins aqueous solutions and for the quantitative determination of thermal denaturation in whey protein concentrate solutions.

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A Rapid Method for Determination of Buprenorphine and Norbuprenorphine in Urine by UPLC-MS/MS

Current Pharmaceutical Analysis ◽

10.2174/1573412916999200627010536 ◽

2020 ◽

Vol 16 ◽

Author(s):

Aykut Kul ◽

Murat Ozdemir ◽

Selma Ozilhan ◽

Olcay Sagirli

Keyword(s):

Forensic Science ◽

Rapid Method ◽

Proficiency Testing ◽

Mass Spectrometer ◽

Illicit Market ◽

Analysis Methods ◽

Accuracy And Precision ◽

Lower Limits

Background: Buprenorphine is quite common in the illicit market. Buprenorphine-containing drugs abuse is frequently encountered in patients. The analysis methods used to determine the abuse of buprenorphine and norbuprenorphine are important for forensic science. Buprenorphine is metabolized to norbuprenorphine by the liver. Objective: Therefore, the determination of buprenorphine and norbuprenorphine in urine is one of the methods to determine the abuse of buprenorphine. Methods: In this study, we have developed a precise, simple, and rapid ultra-performance liquid chromatographytandem mass spectrometer method for the determination of buprenorphine and norbuprenorphine simultaneously. Results: The developed method was validated in terms of selectivity and linearity, which was in the range of 9–1800 ng/mL for both buprenorphine and norbuprenorphine. The intra-assay and inter-assay accuracy and precision were found within acceptable limits of the EMA guideline. Lower limits of quantitation were 9 ng/mL for both buprenorphine and norbuprenorphine. Conclusion: The developed method was successfully applied for the determination of both analytes in the proficiency testing samples.

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A Reliable and Rapid Method for Simultaneous Determination of Furfural and Hydroxymethyl Furfural in Oil Refinery Wastewaters by Ant Colony/Partial Least-Squares Analysis

Journal of Analytical Chemistry ◽

10.1134/s1061934820110039 ◽

2020 ◽

Vol 75 (11) ◽

pp. 1486-1496

Author(s):

Ali Akbar Miran Beigi

Keyword(s):

Least Squares ◽

Simultaneous Determination ◽

Partial Least Squares ◽

Rapid Method ◽

Ant Colony ◽

Oil Refinery ◽

Partial Least Squares Analysis ◽

Hydroxymethyl Furfural

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Rapid method suitable for liquids and powders for determination of relative permittivities in the microwave region

Electronics Letters ◽

10.1049/el:19730027 ◽

1973 ◽

Vol 9 (2) ◽

pp. 39 ◽

Cited By ~ 3

Author(s):

M. Kent

Keyword(s):

Rapid Method ◽

Microwave Region

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Determination of Dimetridazole and Ipronidazole in Feeds at Cross-Contamination Levels

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/71.3.474 ◽

1988 ◽

Vol 71 (3) ◽

pp. 474-477 ◽

Cited By ~ 1

Author(s):

Duane D Hughes

Keyword(s):

Thin Layer ◽

Rapid Method ◽

Aqueous Phase ◽

Borate Buffer ◽

Cross Contamination ◽

Chromatographic System ◽

Arsanilic Acid ◽

Contamination Levels ◽

Benzene Extract

Abstract A rapid method for the determination of dimetridazole and ipronidazole in feeds is described. The compounds are extracted from a borate buffer (pH 8.65) with benzene, partitioned into IN HC1, and then partitioned back into benzene from a basic aqueous phase. The benzene extract is concentrated and injected onto a nonpolar (Apiezon L) gas chromatographic column for determination by 63Ni electroncapture detection. Recoveries from feeds of various composition, spiked at 0.2 ppm with both dimetridazole and ipronidazole, ranged from 70 to 115%; for the same feeds spiked at 1 ppm or more, the recoveries were greater than 80%. Carbadox, furazolidone, levamisole, oxytetracycline, chlortetracycline, sulfamethazine, sulfaquinoxaline, arsanilic acid, piperazine, penicillin, and commonly added vitamins and minerals do not interfere. A 2-dimensional thin layer chromatographic system is presented as a means of additional identification.

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