Development of a histamine aptasensor for food safety monitoring

Abstract

Histamine produced by bacteria through decarboxylation of histidine in spoiled foods such as fish is known to cause food poisoning. Therefore, accurate and facile measurement of histamine is of practical importance. Using the recently discovered RNA aptamer that specifically recognizes histamine (A1-949 aptamer), we developed an aptasensor based on the structure-switching mechanism. Specifically, the aptamer A1-949 was fluorescently labeled at the 5′ end and hybridized with a short quencher DNA strand that is partially complementary to the aptamer. The quencher strand was modified with a fluorescence quencher at its 3′ terminus. Displacement of the quencher strand upon histamine binding results in an increased fluorescence. After optimizing the assay condition, the enantiomeric version of the aptasensor (L-RNA and L-DNA) was synthesized which could detect the achiral analyte with identical sensitivity and improved biochemical stability. The aptasensor performance was validated by measuring fish samples spiked with known concentrations of histamine. Finally, histamine content in spoiled fish samples was measured, and the results were compared with the measurements using a commercial enzymatic assay kit.

Translational control of enzyme scavenger expression with toxin-induced micro RNA switches

“…Most of the recent approaches use an aptamer element to engineer ligand-responsiveness and to regulate gene expression [23][24][25][26]44 . Aptamers are widely used, due to their high binding affinity against their respective target and their specificity [70][71][72][73][74][75][76][77][78][79][80][81][82] . In principal, the process of SELEX (Systematic Evolution of Ligands by Exponential enrichment) allows aptamer selection against any small molecule of interest 83,84 .…”

Characterization and Application of a Histamine Aptamer-Based Biosensor

“…Histamine is naturally found at low levels in food, particularly seafood, meat, cheese, fruits and vegetables. Histamine is also found in fermented drinks such as beer and wine [3,39,40]. Histamine is derived from the decarboxylation of free histidine amino acid that is naturally found in food and sometimes released from proteins as a result of proteolytic cleavage.…”

“…According to Health Canada, the established maximum allowable levels for histamine contaminants in food is 100-200 mg/kg and is routinely enforced by the Canadian Food Inspection Agency. The FDA and European food regulations require maximum histamine levels to not exceed 50 mg/kg and 100 mg/kg, respectively [40]. Other countries have similar upper limits of 100 mg/kg histamine in foods, and 2 mg/L of histamine contaminants in alcoholic beverages [39].…”

“…These methods include instrumental analysis using mass spectrometry and HPLC, offering high sensitivity. However, these are time consuming and expensive sophisticated instruments that require highly skilled labor, which is not ideal for everyday food testing [40,41]. Biosensor method are also emerging as histamine detection techniques that provide a good alternative to traditional methods due to low cost, rapidity, and no need for skilled operators.…”

“…Furthermore, other studies such as Dwidar et al reported an RNA aptamer that specifically recognizes histamine with a KD value of 370 nM acquired by ITC. An aptasensor based on the structure-switching mechanism was also developed that could detect histamine concentrations as low as 1 µM which was used to detect histamine levels in tuna samples[40].Lateral flow assays (LFA) are a paper-based detection device that detects a wide range of targets in a matter of minutes. Due to their low development cost, and ability to detect targets rapidly with high specificity, they have been established for point-of-care applications in diverse fields including, food safety, environmental health, industry quality control, and medical diagnosis[48].…”