Isotope probing

Stable isotopes can be used to follow the fate of a contaminant of concern in the environment without environmental or safety risks associated with radioactive isotopes. Novorem has extensive experience tracing the assimilation of stable isotope labelled compounds into microbes, providing unambiguous evidence that a pollutant is being degraded biologically and even identifying the organisms responsible down to the genus level. Known as stable isotope probing, this technology is most applicable to reduced organic contaminants such as petroleum hydrocarbons, which are assimilated by microbes during biodegradation.

Novorem stocks a wide range of stable isotope labelled contaminants of concern with which we can demonstrate assimilation into biomass present in groundwater samples. Isotope ratio mass spectrometry is used to detect stable isotopes in microbial biomarkers. Novorem monitors label incorporation into DNA or RNA and applies nucleic acid based stable isotope probing protocols (density based separation of labelled and unlabelled nucleic acids, PCR and sequencing) to identify the microbes which have dominated the assimilation of an isotope from a contaminant of concern.

Novorem can also subcontract compound specific isotope analysis (CSIA) to investigate fractionation of natural isotope abundance. When microbes process pollutants they leave behind an isotopic signature that can be diagnostic for the microbial activity. CSIA can be used to generate evidence of biodegradation for organochlorines or hydrocarbons.