Protease Sensor Molecules for Rapid Dairy Spoilage Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for detecting bacterial proteases in dairy products, particularly Pseudomonas spp. proteases, are not sensitive enough and take too long to provide results, making them unsuitable for real-time monitoring of milk spoilage and differentiation from intrinsic factors like plasmin.
Innovation Solution
Development of a Pseudomonas spp. protease sensor molecule with a target sequence containing specific cleavage sites and a detectable label, allowing for rapid detection of protease activity through changes in resonance energy transfer or other measurable signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional methods (FITC casein protease assay, HPLC, ELISA) are used to detect bacterial proteases, then detection can be performed, but the methods are not sensitive enough to detect very low levels of protease and take days to weeks to deliver results
Solution Approach 1:
The patent changes the detection parameters by using a specific peptide substrate (Acetyl-SRQRFK-p-nitroaniline) that undergoes a measurable spectral change when cleaved by bacterial proteases. This allows detection at very low protease concentrations (0.1-10 nM range) and provides rapid results within minutes to hours, resolving the contradiction between sensitivity and detection time
Solution Approach 2:
The patent replaces complex mechanical and chemical manipulation methods (HPLC separation, ELISA antibody binding assays, FITC labeling procedures) with a simpler spectrophotometric assay based on p-nitroaniline release. This substitution enables both high sensitivity detection and rapid results without extensive sample manipulation
2Measurement precision
If conventional methods are used, then protease detection is possible, but they cannot differentiate between Pseudomonas spp. protease and plasmin activity
Solution Approach 1:
The patent applies local quality by designing a peptide substrate with specific amino acid sequence (SRQRFK) that matches the preferred cleavage site of Pseudomonas spp. proteases. This localized specificity at the molecular level allows differentiation between bacterial proteases and plasmin without requiring complex methodological changes
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The sensor enables rapid and sensitive detection of Pseudomonas spp. proteases, potentially within minutes, and can differentiate between bacterial and intrinsic protease activity, improving the management of dairy product spoilage and shelf life.
Implementation Method 1
detecting changes in resonance energy transfer or other measurable signals
Data Source
AI summary
The present invention relates to sensors and methods for detecting bacterial proteases in a sample. In particular, the present invention relates to sensors and methods for detecting Pseudomonas spp. protease activity in a sample. The sensors and methods may be used to detect or predict spoilage of a dairy product. The invention also relates to methods for preparing samples for protease assays.