Trichloroacetic Acid Research Articles

Raziskovanje toksičnosti, ki jo povzroča trikloroocetna kislina na hepato-renalni sistem, in posredovanje prehrane, bogate z deviškim kokosovim oljem

Virgin coconut oil (VCO) is known for many beneficial health effects associated with its phenolic acids and flavonoid contents. We investigated the mechanisms underlying the antioxidative, anti-inflammatory, and anti-apoptotic mechanisms of Virgin Coconut oil-rich diet in treating trichloroacetic acid (TCA)-induced hepatic and renal damage in rats. Rats received TCA (250 mg/Kg b.wt, p.o) for ten days, followed by 5%, 10% or 15% VCO per gram feed for twenty-one days. Serum liver enzymes, urea, creatinine, tissue oxidative stress parameters, and inflammatory and apoptotic markers were then evaluated along with histological examination. TCA raised serum transaminases (ALT, AST), alkaline phosphatase (ALP), total bilirubin, urea and creatinine levels, which were abrogated by a VCO-rich diet dose-dependently. The activity of superoxide dismutase, catalase, glutathione peroxidase and nuclear factor erythroid 2-related factor 2 in the liver and kidney were enhanced, while malondialdehyde, tumour necrosis factor-α, interleukin-1β, nuclear factor-kB level hitherto increased by TCA were quashed by the VCO- rich diet (p<0.05). Similarly, the augmented level of Caspase-3 in the organs exposed to TCA was downregulated in favour of significantly increased BCl-2. Further, histomorphometry data validated the biochemical findings observed for the anti-inflammatory and anti-apoptotic potentials of VCO. Hepatocyte ballooning, pleomorphism and vascular congestion in the liver, loss of tubular architecture, tubular congestion and leukocyte infiltration in the kidney, all occasioned by TCA-intoxication, were evidently mitigated. Virgin coconut oil-rich diet could ameliorate liver and renal injury associated with trichloroacetic acid exposure via antioxidative, anti-inflammatory and anti-apoptotic mechanisms.

Fabrication of functional diatomaceous earth with enhanced papain enzyme adsorption

Diatomaceous earth (DE) is a sedimentary rock comprising fossilized shells of diatoms, which are a type of algae. The shells of the diatoms are made of silicon dioxide, which is also the main component of DE. DE has excellent moisture absorption and desorption properties and is widely used as an adsorbent, abrasive, insulator, catalyst, and carrier in the stationary phase. It has also been widely studied for its application as a new silicon material in emerging growth fields, such as biosensors. However, because organic matter is adsorbed on the surface of DE, the organic matter must be removed to exploit the properties of mesoporous silica. In this study, the organic matter on the DE surface was removed by alkali treatment to expose the pores and increase the adsorption capacity. Additionally, papain was physisorbed onto DE using a rotator, and l-cysteine was added for papain activation. Under these optimised conditions, the activation of the papain enzyme was effective, resulting in improved DE performance. The adsorption power of DE was correlated with the amount of papain adsorbed, which, in turn, was correlated with its absorbance. Trichloroacetic acid was added to stop the reaction, and the absorbance was measured. The prepared samples were designated as papain/DE (P/DE) complexes. The final concentration of the P/DE was 1 mg/mL. In addition, cross-linked and non-cross-linked P/DE samples were prepared using N-hydroxysuccinimide and water-soluble carbodiimide in a 5:3 ratio and compared. The results showed that surface treatment and functionalisation of DE improved its functionality (enzyme activity), indicating its potential as a new DE material.

Polar metabolomics using trichloroacetic acid extraction and porous graphitic carbon stationary phase

IntroductionAccurately identifying and quantifying polar metabolites using untargeted metabolomics has proven challenging in comparison to mid to non-polar metabolites. Hydrophilic interaction chromatography and gas chromatography–mass spectrometry are predominantly used to target polar metabolites.ObjectivesThis study aims to demonstrate a simple one-step extraction combined with liquid chromatography–mass spectrometry (LC–MS) that reliably retains polar metabolites.MethodsThe method involves a MilliQ + 10% trichloroacetic acid extraction from 6 healthy individuals serum, combined with porous graphitic carbon liquid chromatography–mass spectrometry (LC–MS). The coefficient of variation (CV) assessed retention reliability of polar metabolites with logP as low as − 9. QreSS (Quantification, Retention, and System Suitability) internal standards determined the method's consistency and recovery efficiency.ResultsThe method demonstrated reliable retention (CV < 0.30) of polar metabolites within a logP range of − 9.1 to 5.6. QreSS internal standards confirmed consistent performance (CV < 0.16) and effective recovery (70–130%) of polar to mid-polar metabolites. Quality control dilution series demonstrated that ~ 80% of annotated metabolites could be accurately quantified (Pearson’s correlation coefficient > 0.80) within their concentration range. Repeatability was demonstrated through clustering of repeated extractions from a single sample.ConclusionThis LC–MS method is better suited to covering the polar segment of the metabolome than current methods, offering a reliable and efficient approach for accurate quantification of polar metabolites in untargeted metabolomics.

Utilizing an Integrated Flow Cathode-Membrane Filtration System for Effective and Continuous Electrochemical Hydrodechlorination.

Pd-based electrodes are recognized to facilitate effective electrochemical hydrodechlorination (EHDC) as a result of their superior capacity for atomic hydrogen (H*) generation. However, challenges such as electrode stability, feasibility of treating complex matrices, and high cost associated with electrode synthesis hinder the application of Pd-based electrodes for EHDC. In this work, we investigated the feasibility of degrading 2,4-dichlorophenol (2,4-DCP) by EHDC employing Pd-loaded activated carbon particles, prepared via a simple wet-impregnation method, as a flow cathode (FC) suspension. Compared to other Pd-based EHDC studies, a much lower Pd loading (0.02-0.08 mg cm-2) was used. Because of the excellent mass transfer in the FC system, almost 100% 2,4-DCP was hydrodechlorinated to phenol within 1 h. The FC system also showed excellent performance in treating complex water matrices (including hardness ion-containing wastewater and various other chlorinated organics such as 2,4-dichlorobenzoic acid and trichloroacetic acid) with a relatively low energy consumption (0.26-1.56 kW h m-3 mg-1 of 2,4-DCP compared to 0.32-7.61 kW h m-3 mg-1 of 2,4-DCP reported by other studies). The FC synthesized here was stable over 36 h of continuous operation, indicating its potential suitability for real-world applications. Employing experimental investigations and mathematical modeling, we further show that hydrodechlorination of 2,4-DCP occurs via interaction with H*, with no role of direct electron transfer and/or HO•-mediated processes in the removal of 2,4-DCP.

Intralesional Mumps, Measles, Rubella (MMR) Vaccine as Therapy for Recurrent Condyloma Acuminata: A Case Report

Background: Condyloma acuminata (CA), a prevalent sexually transmitted infection caused by the human papillomavirus (HPV), presents challenges in treatment due to its high recurrence rate. While various treatment modalities exist, intralesional immunotherapy with the mumps, measles, rubella (MMR) vaccine has shown promise in managing HPV-related conditions. This case report investigates intralesional MMR vaccine in treating recurrent CA. Case presentation: A 24-year-old female presented with recurrent CA lesions on the labia majora and perianal region. Despite prior treatment with trichloroacetic acid (TCA), the lesions had reappeared. Intralesional MMR vaccine injections were administered twice, one month apart, resulting in complete lesion resolution within six weeks of the second injection. No recurrence was observed during a six-month follow-up period, and the patient reported only mild, transient pain at the injection sites. Conclusion: This case report highlights the potential of intralesional MMR vaccine as an effective and well-tolerated treatment option for recurrent CA. Further research is warranted to validate these findings and establish optimal treatment protocols.

Characteristics of disinfection byproducts from dissolved organic matter during chlor(am)ination of source water in Tibetan Plateau, China

The Tibetan Plateau, a typical high-altitude area, is less affected by human activities such as industrial development, and the external pollution to water sources is extremely low. Then it is also an important source of water samples for exploring the molecular characteristics of precursors in the dissolved organic matter (DOM) of disinfection byproducts (DBPs) in drinking water. Research data on DBPs in drinking water on the Tibet Plateau remains insufficient, leading to uncertainty about DBP contamination in the area. This study explores the formation potential of 35 typical DBPs, including 6 trihalomethanes (THMs), 9 haloacetic acids (HAAs), 2 halogenated ketones (HKs), 9 nitrosamines (NAs), and 9 aromatic DBPs, during chlorination and chloramination of typical source water samples in the Tibet Plateau of China. Moreover, in order to further investigate the characteristics of the generation of DBPs, the molecular composition of DOM in the collected water samples was characterized by Fourier transform ion cyclotron resonance mass spectrometry. The findings reveal that, for chlorination and chloramination, the average concentration of the five classes of DBPs was ranked as follows (chlorination, chloramination): HAAs (268.1 μg/L, 54.2 μg/L) > THMs (44.0 μg/L, 2.0 μg/L) > HKs (0.7 μg/L, 1.8 μg/L) > NAs (26.5 ng/L, 74.6 ng/L) > Aromatics (20.4 ng/L, 19.5 ng/L). The dominant compounds in THMs, HAAs, and NAs are trichloromethane, dichloroacetic acid, trichloroacetic acid, and nitrosopyrrolidine, respectively. This study highlights a significant positive correlation between DBP generation and UV254, SUV254, and the double bond equivalents of DOM in the source water. It systematically elucidates DOM molecular composition characteristics and DBP formation potential in high-altitude water sources, shedding light on key factors influencing DBP generation at the molecular level in high-altitude areas.

A clinical and novel dermoscopic investigation of combined peels as a hand aging treatment.

The hands are one of the areas where skin aging is most noticeable, alongside the face, but limited studies used dermoscopic evaluation on hand aging. The Dermoscopy Photoaging Scale (DPAS) is frequently used to assess face aging but is never used for hand aging. Treating skin aging using chemical peeling is a commonly used method to rejuvenate the skin on the hands, as it is relatively affordable. Using multiple chemical peels may yield more significant results. To determine the effectiveness of a chemical peeling combination in retarding hand aging and to assess the utility of DPAS in this process. This study involved 69 Fitzpatrick skin types III-IV volunteers aged 20-69. One hand of each participant was treated with 20% glycolic acid (GA), while the other received a combination of peels consisting of 20% GA and 15% trichloroacetic acid (TCA). The hands were clinically examined before and after the treatments, and dermoscopic examinations were performed using a modified DPAS. Four treatments improved clinical and dermoscopic characteristics in both hands. The combined peeling considerably improved pigmentation intensity on the dorsal hand compared to the GA peel (p < 0.001). Post-chemical peeling patient satisfaction increased significantly. The modified DPAS is a valuable instrument to assess the signs of hand aging. The combination of GA and TCA effectively improves skin aging of the hands and offers an accessible and economical option for addressing skin aging.

Detection of Serum IgG Specific for Brachyspira pilosicoli and "Brachyspira canis" in Dogs.

Brachyspira pilosicoli (B. pilosicoli) is a pathogen in pigs, poultry, and humans causing colitis, diarrhea, and poor growth rates. Its role as a canine pathogen is controversial, and the seroprevalence of specific IgG antibodies against B. pilosicoli in dogs is unknown. A further, not yet officially recognized Brachyspira species in dogs is "Brachyspira canis" ("B. canis"), which is proposed to be apathogenic. This study evaluates enzyme-linked immunosorbent assays (ELISAs) measuring serum IgG antibodies specific for B. pilosicoli or "B. canis" and investigates levels of specific IgG antibodies against B. pilosicoli and "B. canis" in a cohort of clinical patients presented at an animal referral clinic. These ELISAs use detergent-extracted antigens from B. pilosicoli and "B. canis". To increase analytic specificity, we precipitated the antigens with trichloroacetic acid (TCA) to isolate and concentrate the respective protein fraction. Our results indicate that a large number of serum IgG antibodies bind to shared epitopes of detergent-extracted antigens of the two spirochaetes. Our data also suggest that dogs might not only carry B. pilosicoli but also have "B. canis"-specific serum IgG antibodies.

Comparative histologic evaluation of teeth decalcified by conventional method versus microwave induced decalcification

Abstract Introduction: Complete demineralization of hard tissues with preservation of organic components to retain their tissue architecture and to obtain thin section for histological examination is done by a process known as “decalcification”. Tooth decalcification may be achieved by subjecting the tissue to a decalcifying chemical agent and employing heat, vacuum, or electric current to enhance the procedure. Completion of decalcification is adjudged by determination of end-point. Histological examination of hard tooth tissues and pulp is essential for diagnosis of developmental pathologies, pulp pathologies, and forensic odontology analysis as well as for research purpose. Aim: In our study, we studied the time consumed for decalcification procedure by conventional decalcification method and with the microwave-assisted decalcification method for teeth, using 5% nitric acid, 5% trichloracetic acid, and 14% EDTA (Ethylenediaminetetraacetic acid), respectively, along with morphological preservation of dentin and pulp tissue by analyzing preservation of their issue structure (pulp shrinkage, odontoblastic layer damage) and staining efficacy (patchy staining) for the three types of decalcifying agents used. Materials and Method: The sample for this study included 120 freshly extracted teeth consisting of teeth of mandibular dentition. Samples were divided into two study groups: Group I: Decalcified by Conventional method Group II: Decalcified by Microwave method. Each group consisted of, three sub-groups employing a different decalcifying agent from among the three decalcifying agents used, that is, 5% nitric acids, 5% trichloroacetic acid, and 14%EDTA respectively. Result: The difference in speed of decalcification for both groups showed significant result. In either group, decalcification was fastest using 5% nitric acid. The difference in number of decalcified teeth sections showing shrinkage of pulp was not statistically significant for both groups. Damaged odontoblastic layer was evident only in the teeth treated with 5% nitric acid by microwave method. Patchy staining was observed in a few samples of all sample groups except those decalcified with EDTA by conventional method but the results were not statistically different on intercomparison. Discussion and Conclusion: Our results are similar to those of previous studies and we found that microwave method is an option that can reduce the time of decalcification. Tooth tissue morphology also was noted to be well preserved with 5% trichloracetic acid and 14% EDTA in comparison to 5% Nitric acid.

Determination of unbound platinum concentrations in human plasma using ultrafiltration and precipitation methods

Quantification of the unbound portion of platinum (Pt) in human plasma is important for assessing the pharmacokinetics of the chemotherapeutic drug cisplatin. In this study, we sought to compare the recovery of unbound Pt using Nanosep® filters to 1) traditional filters (Centrifree®, Centrisart®, Amicon®) or trichloroacetic acid (TCA) protein precipitation, and 2) unbound, bound, and total Pt concentrations in clinical specimens. For the tested filters, the impact of 1) molecular weight cut-offs, 2) centrifugation force, and 3) total Pt concentration on Pt binding in human plasma was evaluated. Pt was quantified using inductively coupled-plasma mass spectrometry. In human plasma spiked with 0.9 μg/mL Pt, the percent of unbound Pt increased at higher centrifugation speeds. By comparison, the percent of unbound Pt was highest (42.1%) following TCA protein precipitation. When total Pt was ≤0.9 μg/mL, unbound Pt (∼20–30%) was consistent across filters. Conversely, when plasma was spiked with Pt exceeding 0.9 μg/mL, the percent of unbound Pt increased from 36.5 to 48% using ultrafiltration, compared to 63.4% to 79% with TCA precipitation. In patients receiving cisplatin-containing chemotherapy, the fraction of unbound Pt at concentrations exceeding 0.9 μg/mL ranged between 35 and 90%. Moreover, the unbound fraction of Pt in plasma correlated with the concentration of unbound (R2 = 0.738) and total Pt (R2 = 0.335). In summary, this study demonstrates that 1) the percent of unbound Pt is influenced by total and unbound Pt levels in vitro and in clinical specimens, and 2) ultrafiltration with Nanosep® filters is a feasible method for quantifying unbound Pt concentrations in human plasma.

Copper metal-organic framework for selective detection of florfenicol based on fluorescence sensing in chicken meat

Using a hydrothermal technique, a highly sensitive metal-organic Cu-MOFs sensor has been created to detect florfenicol (FFC) fluorescent in chicken meat. The sensor has demonstrated the ability to respond to the presence of FFC in an aqueous solution with accuracy and selectivity, as evidenced by an increase in fluorescence intensity. The interactions and adsorption mechanism based on hydrogen bonding, π- π, and n-π interactions demonstrate the high sensitivity and specificity of Cu-MOFs towards. FFC was detected quantitatively with a recovery of 96.48–98.79% in chicken meat samples. Within a broad linear range of 1–50 μM, the Cu-MOFs nanosensor exhibits a fast response time of 1 min, a low limit of detection (LOD) of 2.93 μM, and a limit of quantification (LOQ) of 8.80 μM. The potential applicability of the Cu-MOFs nanosensor for the detection of FFC in food matrices is confirmed by the results obtained with high-performance liquid chromatography (HPLC). Chemical compoundsCopper (II) nitrate (PubChem CID: 18616); Terephthalic acid (PubChem CID: 7489); Polyvinyl pyrrolidone (PubChem CID: 486422059); N, N-dimethylformamide (PubChem CID: 6228); Ethyl alcohol (PubChem CID: 702); Hydrochloric acid (PubChem CID: 313); Sodium hydroxide (PubChem CID: 14798); Acetic acid (PubChem CID: 176); Trichloroacetic acid (PubChem CID: 6421); Florfenicol (PubChem CID: 114811).

Urinary haloacetic acid concentrations in relation to sex and thyroid hormones among reproductive-aged men

Sex and thyroid hormones are critical for male reproductive health. However, the associations between haloacetic acid (HAA) exposure – a known endocrine disruptor – and sex and thyroid hormones in humans remains unclear. We thus recruited 502 male participants seeking fertility evaluation from a reproductive center. We measured concentrations of sex and thyroid hormones in a single blood sample and dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in repeated urine samples. Multivariable linear regression models were constructed to evaluate the associations between HAA concentrations and hormone measurements. After adjusting for potential confounders and urinary creatinine concentrations, urinary concentrations of TCAA were inversely associated with serum levels of sex hormone-binding globulin (SHBG), testosterone (T), T/luteinizing hormone ratio (T/LH), and thyroid stimulating hormone (TSH) (all P for trend < 0.10). Compared with participants in the lowest quartile of TCAA concentrations, those in the highest quartile had reduced serum levels of SHGB by 14.2 % (95% CI: −26.7, −3.0 %), T by 11.1 % (95% CI: −21.7, −1.3 %), T/LH by 21.0 % (95% CI: −36.7, −7.1 %), and TSH by 19.1 % (95% CI: −39.7, −1.5 %). Additionally, we observed inverse associations between continuous measurements of urinary HAAs and serum levels of free T, bioactive T, and estradiol. Our findings suggest that male HAA exposure may be associated with disrupted sex and thyroid function.

Improving Fatigue Resistance and Autonomous Switching of pH Responsive Hydrazones by Pulses of a Chemical Fuel.

The chemically triggered reversible switching of pH-responsive hydrazones involves rotary motion-induced configurational changes, serving as a prototype for constructing an array of molecular machines. Typically, the configurational isomerization of such switches into two distinct forms (E/Z) occurs through the alteration of the pH the medium, achieved by successive additions of acid and base stimuli. However, this process results in intermittent operation due to the concomitant accumulation of salt after each cycle, limiting switching performance to only a few cycles (5-6). In this context, we introduce a novel strategy for the autonomous E/Z isomerization of hydrazones in acetonitrile using pulses of trichloroacetic acid as a chemical fuel. The use of this transient acid enabled reversible switching of hydrazones even after 50 cycles without causing significant fatigue. To test the broad viability of the fuel, a series of ortho/para-substituted hydrazones were synthesized and their switching performance was investigated. The analysis of kinetic data showed a strong dependency of switching operations including the lifetime of transient state, on the electronic properties of substituents. Finally, a distinct color change from yellow to orange due to reversible switching of the para-methoxy substituted hydrazone was employed for the creation of rewritable messages on commercially available paper.

Utilizing Dermoscopy for Trichloroacetic Acid (TCA) Therapy Assessment in Genital Verruca.

Utilizing Dermoscopy for Trichloroacetic Acid (TCA) Therapy Assessment in Genital Verruca.

A comparative evaluation of sample preparation techniques for the therapeutic monitoring of carbamazepine in human plasma by RPLC/DAD

Four sample preparation techniques, namely direct protein precipitation through a) trichloroacetic acid addition (PPA) or b) acetonitrile addition (PPO), c) liquid-liquid extraction in n-octanol followed by the direct injection of the organic layer, and d) supramolecular solvent extraction in a tetrahydrofuran/n-octanol/water coacervate (SUPRAS) were evaluated to be used for the RPLC/DAD assay of carbamazepine in human plasma samples, targeting therapeutic monitoring (TM) purposes. The chromatographic approach to separating carbamazepine from human plasma matrices was designed to be a simple gradient elution with an octadecyl chemically modified silica gel stationary phase, and a mobile phase composed of acetonitrile (organic) and HPLC grade water (aqueous), both with 0.1% formic acid. Monitoring at 290 nm allowed for the detection of carbamazepine. After optimizing both sample preparation procedures and chromatographic separation parameters, LOQ values of 3 µg/mL (PPA), 0.6 µg/mL (PPO), 12 ng/mL (LLE) and 50 ng/mL (SUPRAS) were determined. Detector response functions were studied over an interval up to 20 µg/mL (ULOQ).

Synergistic inhibition of Mikania micrantha extract with iodide ion on the corrosion of cold rolled steel in trichloroacetic acid medium

The corrosion inhibition behavior of Mikania micrantha extract (MME) and iodide ion in a synergistic system consisting of 0.10 M trichloroacetic acid (Cl3CCOOH, TCA) on cold rolled steel (CRS) materials and its mechanism was fully investigated by weightlessness, electrochemical, and surface analysis measurements. The results show that MME/I− performs higher inhibition than either MME or I− with a peak inhibition efficiency of 96.3 %. The adsorption of MME, I− and MME/I− on CRS follow with Langmuir isotherm. MME/I− retards both anodic and cathodic reactions. With the MME/I− complex inhibitor, the capacitance arc radius reaches a maximum. The results of scanning electron microscopy (SEM), atomic force microscopy (AFM), and confocal laser scanning microscopy (CLSM) showed that there were obvious adsorbent films on the surface of the suppressed CRS. Compositional analysis of surface adsorbates on CRS by X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (TOF-SIMS) revealed that the main components of the adsorption film on the surface of CRS contained a large number of polar compounds, notably the formation of chemical bonds by iron atoms.

Comparing the Use of 80% Trichloroacetic Acid and 50% Trichloroacetic Acid for the Treatment of Ice Pick Acne Scars.

Chemical reconstruction of skin scars (CROSS) using high concentration trichloroacetic acid (TCA) is a safe, effective, and low-cost treatment for ice pick acne scars. To compare the efficacy and effectiveness of the CROSS technique using 50% TCA and 80% TCA for treating ice pick scars. A nonrandomized, single-blinded, and self-controlled clinical trial was undertaken. Four CROSS sessions were conducted using 50% TCA on the left hemiface and 80% TCA on the right hemiface. The E' chelle d'Evaluation Clinique des Cicatrices d'Acne (ECCA) acne grading scale was used to assess the scars pretreatment and posttreatment. Complications were evaluated after each session. Thirty-one patients participated in our study. Significant differences were found between pretreatment and posttreatment ECCA scores ( p < .0001) on both hemifaces. Scores were significantly lower on the side treated with 80% TCA; however, there was no statistical significance in mean ECCA score differences (pretreatment minus posttreatment) between the 2 treatment sides. The adverse events were more serious on the sides treated with 80% TCA. The CROSS method using TCA was well-tolerated and effective for treating ice pick acne scars. Less severe complications were associated with 50% TCA, whereas efficacy was the same as 80% TCA.

Pre-analytical challenges from adsorptive losses associated with thiamine analysis

Thiamine (vitamin B1) is an essential vitamin serving in its diphosphate form as a cofactor for enzymes in the citric acid cycle and pentose-phosphate pathways. Its concentration reported in the pM and nM range in environmental and clinical analyses prompted our consideration of the components used in pre-analytical processing, including the selection of filters, filter apparatuses, and sample vials. The seemingly innocuous use of glass fiber filters, glass filter flasks, and glass vials, ubiquitous in laboratory analysis of clinical and environmental samples, led to marked thiamine losses. 19.3 nM thiamine was recovered from a 100 nM standard following storage in glass autosampler vials and only 1 nM of thiamine was obtained in the filtrate of a 100 nM thiamine stock passed through a borosilicate glass fiber filter. We further observed a significant shift towards phosphorylated derivatives of thiamine when an equimolar mixture of thiamine, thiamine monophosphate, and thiamine diphosphate was stored in glass (most notably non-silanized glass, where a reduction of 54% of the thiamine peak area was observed) versus polypropylene autosampler vials. The selective losses of thiamine could lead to errors in interpreting the distribution of phosphorylated species in samples. Further, some loss of phosphorylated thiamine derivatives selectively to amber glass vials was observed relative to other glass vials. Our results suggest the use of polymeric filters (including nylon and cellulose acetate) and storage container materials (including polycarbonate and polypropylene) for thiamine handling. Losses to cellulose nitrate and polyethersulfone filters were far less substantial than to glass fiber filters, but were still notable given the low concentrations expected in samples. Thiamine losses were negated when thiamine was stored diluted in trichloroacetic acid or as thiochrome formed in situ, both of which are common practices, but not ubiquitous, in thiamine sample preparation.

Measurement of Serum Vitamins B2 and B6 in Patients with Hashimoto’s Thyroiditis by LC–MS/MS Method

Vitamin B2 and vitamin B6 are cofactors and coenzymes in many biochemical reactions, and their sufficient serum concentrations may be crucial for the proper functioning of the thyroid gland. The aim of the study was to develop and validate a novel high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for the determination of vitamin B2 and vitamin B6 in the serum of patients with Hashimoto’s thyroiditis (HT). Detection of the analytes was performed on a triple-quadrupole MS with multiple reaction monitoring using electrospray ionization. The mobile phase consisted of water and methanol, both containing 0.1% (v/v) formic acid. The analytes were isolated from serum by the one-step sample preparation of the trichloroacetic acid precipitation. Validation parameters, including linearity, accuracy, precision, limits of detection and quantification, and stability, were determined and fulfilled the criteria for analyzing compounds in biological fluids. The method was applied for the determination of the above vitamin concentrations in serum samples of 74 patients with HT and 33 healthy controls. The concentration of vitamin B2 was significantly lower in patients with HT compared to the control group (7.20 ± 7.86 ng/mL vs. 12.03 ± 9.62 ng/mL) and the concentration of vitamin B6 was also lower, but without a statistically significant difference (30.09 ± 19.16 ng/mL vs. 37.29 ± 23.02 ng/mL). We concluded that the vitamins concentration measurement may be helpful in the diagnosis of vitamin deficiencies and the supplementation strategy.

Optimization of Cyanocobalamin (Vitamin B12) Sorption onto Mesoporous Superparamagnetic Iron Oxide Nanoparticles.

The techniques used to detect and quantify cyanocobalamin (vitamin B12) vary considerably in terms of detection sensitivity, from the most sensitive, based on radioisotopes and mass spectrometry (MS) with limits of detection (LOD) in fg mL-1, to fluorescence (FL) and surface plasmon resonance (SPR) biosensors with LOD values in the range of a few µg mL-1. For accurate quantification of an analyte present at trace levels in complex biological matrices, a selective separation and enrichment step is required to overcome matrix interferences and ensure sufficient detection sensitivity. In this study, iron oxide magnetic nanoparticles (IONPs) were used for the extraction and initial preconcentration of cyanocobalamin (vitamin B12). In the dependence of the magnetization on the H-field (hysteresis loop), no coercivity and remanence values were found at 300 K, indicating the superparamagnetic properties of the tested IONPs. Perfluorinated acids were used as amphiphilic agents to allow the sorption of cyanocobalamin onto the IONPs. FT-IR/ATR spectroscopy was used to confirm the sorption of cyanocobalamin on the IONPs. The influence of the addition of a homologous series of perfluorinated acids such as trifluoroacetic acid (TFAA), heptafluorobutyric acid (HFBA), and trichloroacetic acid (TCAA) to the extraction mixture was tested considering their type, mass, and time required for effective sorption. The adsorption kinetics and isotherm, described by the Freundlich and Langmuir equations, were analyzed. The maximum adsorption capacity (qm) exceeded 6 mg g-1 and was 8.9 mg g-1 and 7.7 mg g-1 for HFBA and TCAA, respectively, as the most efficient additives. After the desorption process using aqueous KH2PO4 solution, the sample was finally analyzed spectrophotometrically and chromatographically. The IONP-based method was successfully applied for the isolation of cyanocobalamin from human urine samples. The results showed that the developed approach is simple, cheap, accurate, and efficient for the determination of traces of cyanocobalamin in biological matrices.