SPOTplasma has been persistent in its pursuit of developing innovative tools to transform the analysis of DBFS through the exploration of novel and affordable methodologies based in AI-MS. The project was focused on uncovering and harnessing the latent potential of the FμTP as an ionization source for DBFS. The distinctive nature of this ion source renders it both alluring and formidable. To better understand the ion source, an evaluation was conducted to ascertain its ionization capacity comparing it to analogous plasma-based ion sources. Remarkably, the FμTP exhibited a comparable internal energy distribution to its counterparts. However, the miniaturization character of the ion source proved to be a double-edged sword, as the low flow rates presented challenges in the direct analysis of DBFS.
A variety of approaches was explored, all while staying true to the core principle of SPOTplasma: rapid and easily accessible methodologies. One example was the exploration of a low-cost desorption tool, a handheld IR laser, followed by subsequent ionization utilizing the FμTP. When the laser was utilized, rapid pulses of heat were precisely administered to the paper, mitigating the risk of paper combustion or long waiting times associated with conventional heat sources. This method not only demonstrated the efficacy of carefully selected extraction solvents in conjunction with optimized laser and FμTP conditions, but also facilitated the direct analysis of drugs in biofluids such as saliva, blood, plasma, and other samples deposited on paper, including beverages and tap water.
Indeed, the paper serves not only as a substrate for DBFS collection but can also serve as the substrate for ionization. Paper spray-MS has emerged as an ideal technique for the direct analysis of biological samples, including urine, tissue, and blood, crucial for disease detection and diagnosis. This is largely attributed to the paper substrate's minimal sample consumption, stability, affordability, and ease of disposal. Furthermore, the paper spray-MS methodology requires a few experimental prerequisites, encompassing voltage, solvent selection, and detection protocols. To this end, a refined approach involving thick film reaction on paper derivatization was investigated to facilitate the swift diagnosis of amino acid-based metabolic disorders, an area of utmost importance in NBS. A pioneering first-tier method was proposed, enabling NBS analysis to be completed in less than 10 minutes.
The achievements of SPOTplasma have highlighted the importance of innovative research approaches and the pivotal role of AI-MS in the implementation of cutting-edge tools within the realm of clinical chemistry. The project has yielded significant outcomes, with select results already published in peer-reviewed journals and further endeavors currently underway. These remarkable findings have been presented at international conferences, with dedicated efforts directed toward disseminating knowledge on plasma-based ionization, NBS, and MS, thus extending the project's reach to the wider public.
