Journal: Food Chemistry: Molecular Sciences

Article Title: Usage of nanobody-beta-galactosidase fusion in immunoassays and its application in detecting a peanut allergen

doi: 10.1016/j.fochms.2026.100357

Figure Lengend Snippet: β-Gal detection of the association between its fusion partner Nb16 and Ara h 3 by ELISA. The utility of β-gal as a colorimetric enzyme in ELISA was assessed. Nb16-βgal association with Ara h 3 coated on the surface of the wells, but not with the control proteins, was detected. (A) SDS-PAGE analysis of Ara h 3 and control proteins used to coat the microplate. Nonreduced (lane 1) and reduced (lane 2) Ara h 3 were separated on a 4–12% SDS gel and stained with CBB. Chicken allergen Gal d 2 (lane 3) and cow's milk allergen Bos d 4 (lane 4) were included as control samples. The molecular masses (in kDa) of the proteins in the marker (lane M) are shown on the right side of the gel images. (B) The kinetic curves of the signal readout during plate incubation after the β-gal substrate ONPG was added. The black line shows the average signal of the wells incubated with TBS during the coating step. Red, green, and blue lines show the average signals of the wells coated with Gal d 2, Bos d 4, and Ara h 3, respectively. All the coating samples were at a concentration of 20 μg/mL. (C) A bar representation of β-gal detection in the ELISA experiment using the endpoint data. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Milli-Q water was purified in-house using a Milli-Q Advantage A10 system (Millipore, Bedford, MA, USA) and used throughout. o -Nitrophenyl-β-galactoside (ONPG), Isopropyl β-D-1-thiogalactopyranoside (IPTG), Kanamycin (Kan), and X-Gal were purchased from GoldBio (St Louis, MO, USA).

Techniques: Enzyme-linked Immunosorbent Assay, Control, SDS Page, SDS-Gel, Staining, Marker, Incubation, Concentration Assay

Journal: Food Chemistry: Molecular Sciences

Article Title: Usage of nanobody-beta-galactosidase fusion in immunoassays and its application in detecting a peanut allergen

doi: 10.1016/j.fochms.2026.100357

Figure Lengend Snippet: Detection of peanut allergen Ara h 3 at various concentrations. (A) Plate wells were coated with Ara h 3 at the concentrations indicated below the bar plot. Results were analyzed as described in C, but without background (signal for [Ara h 3] = 0) correction. (B) Kinetic signal readout during plate incubation after the β-gal substrate ONPG was added. Ara h 3 concentrations are indicated next to the endpoint signals. (C) The slopes of the linear fit to the kinetic data are shown in a bar graph. The Ara h 3 concentrations in the coating samples are indicated under the bars. (D) The slope of the kinetic data as a function of the Ara h 3 concentration is shown. The red straight line shows the results of fitting the data for Ara h 3 concentrations <2.5 μg/mL. (E) A semi-log plot of the slopes of the β-gal signal against the Ara h 3 concentration. The red sigmoidal line shows the result of a four-parameter logistic curve fit. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Milli-Q water was purified in-house using a Milli-Q Advantage A10 system (Millipore, Bedford, MA, USA) and used throughout. o -Nitrophenyl-β-galactoside (ONPG), Isopropyl β-D-1-thiogalactopyranoside (IPTG), Kanamycin (Kan), and X-Gal were purchased from GoldBio (St Louis, MO, USA).

Techniques: Incubation, Concentration Assay

Journal: Food Chemistry: Molecular Sciences

Article Title: Usage of nanobody-beta-galactosidase fusion in immunoassays and its application in detecting a peanut allergen

doi: 10.1016/j.fochms.2026.100357

Figure Lengend Snippet: Direct ELISA detection of peanut proteins in baked food. Kinetic signal readout during plate incubation with β-gal substrate ONPG. Each data point is the average of three triplicate wells. Data obtained by coating the plate with diluted muffin extract at peanut protein concentrations of 1.56, 3.13, 6.25, 15.63, and 39.06 ppm are shown in red, green, blue, cyan, and magenta, respectively. Data for the negative control, with wells treated with TBS during coating, are shown in black. Linear fits were applied to each data set, and the y-axis intercept of each fit was subtracted from each data point to shift the data set vertically. The straight lines are the results of linear fits of the shifted data. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Milli-Q water was purified in-house using a Milli-Q Advantage A10 system (Millipore, Bedford, MA, USA) and used throughout. o -Nitrophenyl-β-galactoside (ONPG), Isopropyl β-D-1-thiogalactopyranoside (IPTG), Kanamycin (Kan), and X-Gal were purchased from GoldBio (St Louis, MO, USA).

Techniques: Direct ELISA, Incubation, Negative Control