Portable Mid-Infrared Spectroscopy Combined with Chemometrics to Diagnose Fibromyalgia and Other Rheumatologic Syndromes Using Rapid Volumetric Absorptive Microsampling.

The diagnostic criteria for fibromyalgia (FM) have relied heavily on subjective reports of experienced symptoms coupled with examination-based evidence of diffuse tenderness due to the lack of reliable biomarkers. Rheumatic disorders that are common causes of chronic pain such as rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, and chronic low back pain are frequently found to be comorbid with FM. As a result, this can make the diagnosis of FM more challenging. We aim to develop a reliable classification algorithm using unique spectral profiles of portable FT-MIR that can be used as a real-time point-of-care device for the screening of FM. A novel volumetric absorptive microsampling (VAMS) technique ensured sample volume accuracies and minimized the variation introduced due to hematocrit-based bias. Blood samples from 337 subjects with different disorders (179 FM, 158 non-FM) collected with VAMS were analyzed. A semi-permeable membrane filtration approach was used to extract the blood samples, and spectral data were collected using a portable FT-MIR spectrometer. The OPLS-DA algorithm enabled the classification of the spectra into their corresponding classes with 84% accuracy, 83% sensitivity, and 85% specificity. The OPLS-DA regression plot indicated that spectral regions associated with amide bands and amino acids were responsible for discrimination patterns and can be potentially used as spectral biomarkers to differentiate FM and other rheumatic diseases.

Metabolic Fingerprinting for the Diagnosis of Clinically Similar Long COVID and Fibromyalgia Using a Portable FT-MIR Spectroscopic Combined with Chemometrics.

Post Acute Sequelae of SARS-CoV-2 infection (PASC or Long COVID) is characterized by lingering symptomatology post-initial COVID-19 illness that is often debilitating. It is seen in up to 30-40% of individuals post-infection. Patients with Long COVID (LC) suffer from dysautonomia, malaise, fatigue, and pain, amongst a multitude of other symptoms. Fibromyalgia (FM) is a chronic musculoskeletal pain disorder that often leads to functional disability and severe impairment of quality of life. LC and FM share several clinical features, including pain that often makes them indistinguishable. The aim of this study is to develop a metabolic fingerprinting approach using portable Fourier-transform mid-infrared (FT-MIR) spectroscopic techniques to diagnose clinically similar LC and FM. Blood samples were obtained from LC (n = 50) and FM (n = 50) patients and stored on conventional bloodspot protein saver cards. A semi-permeable membrane filtration approach was used to extract the blood samples, and spectral data were collected using a portable FT-MIR spectrometer. Through the deconvolution analysis of the spectral data, a distinct spectral marker at 1565 cm-1 was identified based on a statistically significant analysis, only present in FM patients. This IR band has been linked to the presence of side chains of glutamate. An OPLS-DA algorithm created using the spectral region 1500 to 1700 cm-1 enabled the classification of the spectra into their corresponding classes (Rcv > 0.96) with 100% accuracy and specificity. This high-throughput approach allows unique metabolic signatures associated with LC and FM to be identified, allowing these conditions to be distinguished and implemented for in-clinic diagnostics, which is crucial to guide future therapeutic approaches.

Polyphenol Loaded W1/O/W2 Emulsions Stabilized with Lesser Mealworm (Alphitobius diaperinus) Protein Concentrate Produced by Membrane Emulsification: Stability under Simulated Storage, Process, and Digestion Conditions.

Water-in-oil-in-water (W1/O/W2) emulsions are complex delivery systems for polyphenols amongst other bio-actives. To stabilize the oil-water interphase, dairy proteins are commonly employed, which are ideally replaced by other, more sustainable sources, such as insect proteins. In this study, lesser mealworm (Alphitobius diaperinus) protein concentrate (LMPC) is assessed and compared to whey protein (WPI) and pea protein (PPI), to stabilize W1/O/W2 emulsions and encapsulate a commercial polyphenol. The results show that LMPC is able to stabilize W1/O/W2 emulsions comparably to whey protein and pea protein when using a low-energy membrane emulsification system. The final droplet size (d4,3) is 7.4 µm and encapsulation efficiency is between 72 and 74%, regardless of the protein used. Under acidic conditions, the LMPC shows a similar performance to whey protein and outperforms pea protein. Under alkaline conditions, the three proteins perform similarly, while the LMPC-stabilized emulsions are less able to withstand osmotic pressure differences. The LMPC stabilized emulsions are also more prone to droplet coalescence after a freeze-thaw cycle than the WPI-stabilized ones, but they are the most stable when exposed to the highest temperatures tested (90 °C). The results show LMPC's ability to stabilize multiple emulsions and encapsulate a polyphenol, which opens the door for application in foods.

Encapsulation of grape seed phenolic-rich extract within W/O/W emulsions stabilized with complexed biopolymers: Evaluation of their stability and release.

The ability of electrostatic complexes made up of sodium caseinate (NaCAS) and a polysaccharide, carboxymethyl cellulose (CMC) or gum Arabic (GA), to retain polyphenols from grape seed extract when encapsulated in W1/O/W2 emulsions was compared to that of the single NaCAS (1%). Both electrostatic complexes (0.5% NaCAS - 0.375% CMC and 0.5% NaCAS - 0.5%GA at pH 5.6) used as hydrophilic emulsifiers in W1/O/W2 were able to stabilize the O/W2 interface for 14 days, even though their protein content was reduced by a 50% regarding that of the emulsions only stabilized with NaCAS. Moreover, interfacial adsorption did not show significant differences between NaCAS-polysaccharide electrostatic complexes and the single NaCAS. In terms of interfacial barrier properties, the rate of polyphenol release during storage was not affected by the type of hydrophilic emulsifier. Since polyphenol transport in W1/O/W2 emulsions was diffusion controlled, interfacial adsorption was considered the main factor limiting polyphenol retention.

Attenuated total reflection infrared microspectroscopy combined with multivariate analysis: a novel tool to study the presence of cocoa polyphenol metabolites in urine samples.

The detection and quantification of polyphenols in biological samples is mainly performed by liquid chromatography in tandem with mass spectrometry (HPLC-MS/MS). This technique requires the use of organic solvents and needs control and maintenance of several MS/MS parameters, which makes the method expensive and time consuming. The main objective of this study was to evaluate, for the first time, the potential of using attenuated total reflection infrared microspectroscopy (ATR-IRMS) coupled with multivariate analysis to detect and quantify phenolic compounds excreted in human urine. Samples were collected from 5 healthy volunteers before and 6, 12 and 24 h after ingestion of 40 g cocoa powder with 250 mL of water or whole milk, and stored at -80 °C. Each sample was centrifuged at 5000 rpm for 10 min and at 4 °C and applied onto grids of a hydrophobic membrane. Spectra were collected in the attenuated total reflection (ATR) mode in the mid-infrared region (4000-800 cm(-1)) and were analyzed by a multivariate analysis technique, soft independent modeling of class analogy (SIMCA). Spectral models showed that IR bands responsible for chemical differences among samples were related to aromatic rings. Therefore, ATR-IRMS could be an interesting and straightforward technique for the detection of phenolic compounds excreted in urine. Moreover, it could be a valuable tool in studies aimed to identify biomarkers of consumption of polyphenol-rich diets.