Rarely in the NTA space have we seen the application of other separation (e.g. elctrophoresis) and ionization techniques such as Inductively Coupled Plasma Mass Spectrometry (ICPMS), Matrix-Assisted Laser Desorption/Ionization (MALDI). For identification of chemicals that may impact humans through surface contact or inhalation of particles, other ambient ionization techniques have emerged including Direct-Analysis in Real-Time (DART) and Desorption Electrospray Ionization (DESI). These platforms have been used heavily in forensic science for identification of bulk drug or explosives materials or diagnostic markers in contact evidence, such as illicit drug metabolites in fingermarks. Other more recent developments include rapid Evaporative Ionization (REIMS) or Laser Desorption Ionisation (LDI) which have both been integrated within surgical blades to rapidly classify biological materials in real-time through identification of discriminating biomolecules. While other ionization sources exist, these are also rarely used and as is the use of multiple ionization sources working in parallel or tandem configurations. Even the application of positive/negative switching ionization remains limited. Besides instrumental ionization techniques, chemical ionization such as derivatization can be conducted offline or even online and in some cases may even lead to better chromatographic separation.