An Automated Micro Solid-Phase Extraction (μSPE) Liquid Chromatography-Mass Spectrometry Method for Cyclophosphamide and Iphosphamide: Biological Monitoring in Antineoplastic Drug (AD) Occupational Exposure

Despite the considerable steps taken in the last decade in the context of antineoplastic drug (AD) handling procedures, their mutagenic effect still poses a threat to healthcare personnel actively involved in compounding and administration units. Biological monitoring procedures usually require large volumes of sample and extraction solvents, or do not provide adequate sensitivity. It is here proposed a fast and automated method to evaluate the urinary levels of cyclophosphamide and iphosphamide, composed of a miniaturized solid phase extraction (µSPE) followed by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. The extraction procedure, developed through design of experiments (DoE) on the ePrep One Workstation, required a total time of 9.5 min per sample, with recoveries of 77-79% and a solvent consumption lower than 1.5 mL per 1 mL of urine sample. Thanks to the UHPLC-MS/MS method, the limits of quantification (LOQ) obtained were lower than 10 pg/mL. The analytical procedure was successfully applied to 23 urine samples from compounding wards of four Italian hospitals, which resulted in contaminations between 27 and 182 pg/mL.

A New Perspective on SPME and SPME Arrow: Formaldehyde Determination by On-Sample Derivatization Coupled with Multiple and Cooling-Assisted Extractions

Formaldehyde (FA) is a toxic compound and a human carcinogen. Regulating FA-releasing substances in commercial goods is a growing and interesting topic: worldwide production sectors, like food industries, textiles, wood manufacture, and cosmetics, are involved. Thus, there is a need for sensitive, economical, and specific FA monitoring tools. Solid-phase microextraction (SPME), with O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) on-sample derivatization and gas chromatography, is proposed for FA monitoring of real-life samples. This study reports the use of polydimethylsiloxane (PDMS) as a sorbent phase combined with innovative commercial methods, such as multiple SPME (MSPME) and cooling-assisted SPME, for FA determination. Critical steps, such as extraction and sampling, were evaluated in method development. The derivatization was performed at 60 °C for 30 min, followed by 15 min sampling at 10 °C, in three cycles (SPME Arrow) or six cycles (SPME). The sensitivity was satisfactory for the method's purposes (LOD-LOQ at 11-36 ng L^-1, and 8-26 ng L^-1, for SPME and SPME Arrow, respectively). The method's linearity ranges from the lower LOQ at trace level (ng L^-1) to the upper LOQ at 40 mg L^-1. The precision range was 5.7-10.2% and 4.8-9.6% and the accuracy was 97.4% and 96.3% for SPME and SPME Arrow, respectively. The cooling MSPME set-up applied to real commercial goods provided results of quality comparable to previously published data.

Design of Novel Mechanically Resistant and Biodegradable Multichannel Platforms for the Treatment of Peripheral Nerve Injuries

Peripheral nerve injury is one of the most debilitating pathologies that severely impair patients' life. Although many efforts have been made to advance in the treatment of such a complex disorder, successful strategies to ensure full recovery are still scarce. The aim of the present work was to develop flexible and mechanically resistant platforms intended to act as a support and guide for neural cells during the regeneration process of peripheral nerve injury. For this purpose, poly(lactic-co-glycolic acid) (PLGA)/poly(d,l-lactic acid) (PDLLA)/poly(ethylene glycol) 400 (PEG)-multichannel-based scaffolds (MCs) were prepared through a multistep process involving electrospun microfibers coated with a polymer blend solution and used as a sacrificial mold. In particular, scaffolds characterized by random (MCR) and aligned (MCA) multichannel were obtained. A design of experiments approach (DoE) was employed to identify a scaffold-optimized composition. MCs were characterized for morphological and mechanical properties, suturability, degradability, cell colonization, and in vivo safety. A new biodegradable, biocompatible, and safe microscale multichannel scaffold was developed as the result of an easy multistep procedure.

Nanoemulsions of Clove Oil Stabilized with Chitosan Oleate-Antioxidant and Wound-Healing Activity

Clove oil (CO) is a powerful antioxidant essential oil (EO) with anti-inflammatory, anesthetic, and anti-infective properties. It can be therefore considered a good candidate for wound-healing applications, especially for chronic or diabetic wounds or burns, where the balance of reactive oxygen species (ROS) production and detoxification is altered. However, EOs require suitable formulations to be efficiently administered in moist wound environments. Chitosan hydrophobically modified by an ionic interaction with oleic acid (chitosan oleate, CSO) was used in the present work to stabilize CO nanoemulsions (NEs). The dimensions of the NE were maintained at around 300 nm as the volume distribution for up to six months, and the CO content did not decrease to under 80% over 4 months, confirming the good stabilizing properties of CSO. The antioxidant properties of the CO NE were evaluated in vitro by a 2,2-diphenil-2-picrylhydrazyl hydrate (DPPH) assay, and in fibroblast cell lines by electron paramagnetic resonance (EPR) using α-phenyl-N-tert-butyl nitrone (PBN) as a spin trap; a protective effect was obtained comparable to that obtained with α-tocopherol treatment. In a murine burn model, the ability of CO formulations to favor macroscopic wound closure was evidenced, and a histological analysis revealed a positive effect of the CO NE on the reparation of the lesion after 18 days. Samples of wounds at 7 days were subjected to a histological analysis and parallel dosage of lipid peroxidation by means of a thiobarbituric acid-reactive substances (TBARS) assay, confirming the antioxidant and anti-inflammatory activity of the CO NE.

Dead migrants in the Mediterranean: genetic analysis of bone samples exposed to seawater

In April 2015, a fishing boat that departed from Libya with about 1,000 migrants on board sank in the Mediterranean Sea. Most of the migrants were packed in the hull of the boat and drowned in the shipwreck. After fifteen months, the ship was recovered from the seabed and brought to a Sicilian naval area for forensic investigations. Skeletal remains belonging to more than 700 people were retrieved. A selected sample composed of 80 victims was considered in order to evaluate the possibility of achieving genetic profiles useful for a positive identification from these challenging specimens. The molecular features of the DNA recovered from a significant number of real casework samples exposed to seawater for long periods of time were described for the first time. Three different DNA extraction protocols and three different commercial kits were employed in order to generate genetic profiles based on the characterization of 21 autosomal STR loci. The combination of multiple DNA extractions and the cross-checking of multiple PCR amplifications with different kits allowed to obtain reliable genetic profiles characterized by at least 16 STR markers in more than 70% of the samples. The factors that could have affected the different quality of the genetic profiles were investigated and the bone preservation was examined through microscopic and macroscopic analyses. The approach presented in this study could be useful in the management of the genetic analysis of bone samples collected in other similar DVI scenarios. The genetic profiles recovered from the bone samples will be compared in kinship analysis to putative relatives of the victims collected in Africa in order to obtain positive identifications.

Freeze-Dried Mesenchymal Stem Cell-Secretome Pharmaceuticalization: Optimization of Formulation and Manufacturing Process Robustness

Producing mesenchymal stem cell (MSC)-secretome for dose escalation studies and clinical practice requires scalable and good manufacturing practice (GMP)-compliant production procedures and formulation into a standardized medicinal product. Starting from a method that combines ultrafiltration and freeze-drying to transform MSC-secretome into a pharmaceutical product, the lyosecretome, this work aims to: (i) optimize the lyosecretome formulation; (ii) investigate sources of variability that can affect the robustness of the manufacturing process; (iii) modify the ultrafiltration step to obtain a more standardized final product. Design of experiments and principal component analysis of the data were used to study the influence of batch production, lyophilization, mannitol (M)/sucrose (S) binary mixture, selected as cryoprotectant excipients, and the total amount of excipients on the extracellular vesicles (EV) particle size, the protein and lipid content and the in vitro anti-elastase. The different excipients ratios did not affect residual moisture or EV particle size; simultaneously, proteins and lipids were better preserved in the freeze-dried product using the maximum total concentration of excipients (1.5% w/v) with a M:S ratio of about 60% w/w. The anti-elastase activity was instead better preserved using 0.5% w/w of M as excipient. The secretome batch showed to be the primary source of variability; therefore, the manufacturing process has been modified and then validated: the final product is now concentrated to reach a specific protein (and lipid) concentration instead of cell equivalent concentration. The new standardization approach led to a final product with more reproducible quali-quantitative composition and higher biological activity.

An Upgrade of Apparatus and Measurement Systems for Generation of Gaseous Formaldehyde: A Review

Formaldehyde (FA) is ubiquitous in the atmospheric environment. It is generally the dominant atmospheric carbonyl compound. Due to its well-known carcinogenicity, FA is a compound that arises the attention in the scientific community. In studies concerning the toxicological effects of FA on humans, animals, and the environment, testing and calibration of air sampling systems and analytical instruments are pivotal. Therefore, the preparation of controllable standard gaseous atmospheres containing FA at levels known with precision and accuracy is essential. This review summarizes the procedures for generating the FA atmosphere, given that operative solutions have been evolving recently. Furthermore, an overview on the available system to collect and store gaseous standard is reported. The progressively implemented FA generation techniques, together with commercially-available instruments, are herein described, classified, and compared.

A review of micro-solid-phase extraction techniques and devices applied in sample pretreatment coupled with chromatographic analysis

Sample pretreatment is one of the most crucial and error-prone steps of an analytical procedure; it consents to improve selectivity and sensitivity by sample clean-up and pre-concentration. Nowadays, the arousing interest in greener and sustainable analytical chemistry has increased the development of microextraction techniques as alternative sample preparation procedures. In this review, we aimed to show two different categorizations of the most used micro-solid-phase extraction (μSPE) techniques. In essence, the first one concerns the solid-phase extraction (SPE) sorbent selection and structure: normal-phase, reversed-phase, ion-exchange, mixed-mode, molecular imprinted polymer, and special techniques (e.g., doped cartridges for specific analytes). The second is a grouping of the commercially available μSPE products in categories and sub-categories. We present every device and technology into the classifications paying attention to their historical development and the actual state of the art. So, this study aims to provide the state-of-the-art of μSPE techniques, highlighting their advantages, disadvantages, and possible future developments in sample pretreatment.

Microwave-Assisted Extraction and HPLC-UV-CD Determination of (S)-usnic Acid in Cladonia foliacea

During the years, many usnic acid (UA) conjugates have been synthesized to obtain potent endowed with biological properties. Since (S)-UA is less abundant in nature than (R)-enantiomer, it is difficult to source, thus precluding a deeper investigation. Among the lichens producing UA, Cladonia foliacea is a valuable (S)-UA source. In the present work, we report on a rapid HPLC-UV/PAD-CD protocol suitable for the analysis and the identification of the main secondary metabolites present in C. foliacea extract. Best results were achieved using XBridge Phenyl column and acetonitrile and water, which were both added with formic acid as mobile phase in gradient elution. By combining analytical, spectroscopical, and chiroptical analysis, the most abundant analyte was unambiguously identified as (S)-UA. Accordingly, a versatile microwave-assisted extractive (MAE) protocol, assisted by a design of experiment (DoE), to quantitatively recover (S)-UA was set up. The best result in terms of UA extraction yield was obtained using ethanol and heating at 80 °C under microwave irradiation for 5 min. Starting from 100 g of dried C. foliacea, 420 mg of (S)-UA were achieved. Thus, our extraction method resulted in a suitable protocol to produce (S)-UA from C. foliacea for biological and pharmaceutical investigation or commercial purposes.

GMP-compliant sponge-like dressing containing MSC lyo-secretome: Proteomic network of healing in a murine wound model

Chronic wounds account for 3% of total healthcare expenditure of developed countries; thus, innovative therapies, including Mesenchymal Stem Cells (MSCs) end their exosomes are increasingly considered, even if the activity depends on the whole secretome, made of both soluble proteins and extracellular vesicles. In this work, we prove for the first time the in vivo activity of the whole secretome formulated in a sponge-like alginate wound dressing to obtain the controlled release of bioactive substances. The product has been prepared in a public GMP-compliant facility by a scalable process; based on the murine model, treated wounds healed faster than controls without complications or infections. The treatment induced a higher acute inflammatory process in a short time and sustained the proliferative phase by accelerating fibroblast migration, granulation tissue formation, neovascularization and collagen deposition. The efficacy was substantially supported by the agreement between histological and proteomic findings. In addition to functional modules related to proteolysis, complement and coagulation cascades, protein folding and ECM remodeling, in treated skin, emerged the role of specific wound healing related proteins, including Tenascin (Tnc), Decorin (Dcn) and Epidermal growth factor receptor (EGFR). Of note, Decorin and Tenascin were also components of secretome, and network analysis suggests a potential role in regulating EGFR. Although further experiments will be necessary to characterize better the molecular keys induced by treatment, overall, our results confirm the whole secretome efficacy as novel "cell-free therapy". Also, sponge-like topical dressing containing the whole secretome, GMP- compliant and "ready-off-the-shelf", may represent a relevant point to facilitate its translation into the clinic.

Liquid phase microextraction techniques combined with chromatography analysis: a review

Sample pretreatment is the first and the most important step of an analytical procedure. In routine analysis, liquid–liquid microextraction (LLE) is the most widely used sample pre-treatment technique, whose goal is to isolate the target analytes, provide enrichment, with cleanup to lower the chemical noise, and enhance the signal. The use of extensive volumes of hazardous organic solvents and production of large amounts of waste make LLE procedures unsuitable for modern, highly automated laboratories, expensive, and environmentally unfriendly. In the past two decades, liquid-phase microextraction (LPME) was introduced to overcome these drawbacks. Thanks to the need of only a few microliters of extraction solvent, LPME techniques have been widely adopted by the scientific community. The aim of this review is to report on the state-of-the-art LPME techniques used in gas and liquid chromatography. Attention was paid to the classification of the LPME operating modes, to the historical contextualization of LPME applications, and to the advantages of microextraction in methods respecting the value of green analytical chemistry. Technical aspects such as description of methodology selected in method development for routine use, specific variants of LPME developed for complex matrices, derivatization, and enrichment techniques are also discussed.

Solid phase microextraction techniques used for gas chromatography: a review

In the last decade, the development and adoption of greener and sustainable microextraction techniques have been proved to be an effective alternative to classical sample preparation procedures. In this review, 10 commercially available solid-phase microextraction systems are presented, with special attention to the appraisal of their analytical, bioanalytical, and environmental engineering. This review provides an overview of the challenges and achievements in the application of fully automated miniaturized sample preparation methods in analytical laboratories. Both theoretical and practical aspects of these environment-friendly preparation approaches are discussed. The application of chemometrics in method development is also discussed. We are convinced that green analytical chemistry will be really useful in the years ahead. The application of cheap, fast, automated, “clever”, and environmentally safe procedures to environmental, clinical, and food analysis will improve significantly the quality of the analytical data.

Growth Factors Delivery System for Skin Regeneration: An Advanced Wound Dressing

Standard treatments of chronic skin ulcers based on the direct application of dressings still present several limits with regard to a complete tissue regeneration. Innovative strategies in tissue engineering offer materials that can tune cell behavior and promote growth tissue favoring cell recruitment in the early stages of wound healing. A combination of Alginate (Alg), Sericin (SS) with Platelet Lysate (PL), as a freeze-dried sponge, is proposed to generate a bioactive wound dressing to care skin lesions. Biomembranes at different composition were tested for the release of platelet growth factors, cytotoxicity, protective effects against oxidative stress and cell proliferation induction. The highest level of the growth factors release occurred within 48 h, an optimized time to burst a healing process in vivo; the presence of SS differently modulated the release of the factors by interaction with the proteins composing the biomembranes. Any cytotoxicity was registered, whereas a capability to protect cells against oxidative stress and induce proliferation was observed when PL was included in the biomembrane. In a mouse skin lesion model, the biomembranes with PL promoted the healing process, inducing an accelerated and more pronounced burst of inflammation, formation of granulation tissue and new collagen deposition, leading to a more rapid skin regeneration.

Highly degraded RNA can still provide molecular information: An in vitro approach

The long-term survival of RNA in postmortem tissues is a tricky topic. Many aged/forensic specimens show, in fact, high rates of null/inconclusive PCR-based results, while reliable outcomes were sometimes achieved from archaeological samples. On the other hand, several data show that the RNA is a molecule that survives even to several physical-chemical stresses. In the present study, a simple protocol, which was already developed for the prolonged hydrolysis of DNA, was applied to a RNA sample extracted from blood. This protocol is based on the heat-mediated (70°C) hydrolysis for up to 36 h using ultrapure water and di-ethyl-pyro-carbonate-water as hydrolysis medium. Measurable levels of depurination were not found even if microfluidic devices showed a progressive pattern of degradation. The reverse transcription/quantitative PCR analysis of two (60 bp long) housekeeping targets (glyceraldehyde-3-phosphate dehydrogenase and porphobilinogen deaminase) showed that the percentage of amplifiable target (%AT) decreased in relation to the duration of the damaging treatment (r² > 0.973). The comparison of the %AT in the degraded RNA and in the DNA samples that underwent the same damaging treatment showed that the %AT is always higher in RNA, reaching up to three orders of magnitude. Lastly, even the end-point PCR of blood-specific markers gave reliable results, which is in agreement with the body fluid origin of the sample. In conclusion, all the PCR-based results show that RNA maintains the ability to be retro-transcribed in short cDNA fragments even after 36 h of incubation at 70°C in mildly acidic buffers. It is therefore likely that the long-term survival of RNA samples depends mainly on the protection against RNAase attacks rather than on environmental factors (such as humidity and acidity) that are instead of great importance for the stability of DNA. As a final remark, our results suggest that the RNA analysis can be successfully performed even when DNA profiling failed.

On the long term storage of forensic DNA in water

A rectrospective study was conducted on the effect of the long term storage of 122 DNA samples resuspended in water, one of the elution media still suggested by well established protocols. These DNA samples come from four different kinds of forensically relevant samples (saliva swabs, FTA card bloodstains, nails and II° World War bones) extracted in 2008-2018 and stored at - 20°C (n=113 of groups #1-#5) and at +4°C (n=9 of the group #6), respectively. At the time of the present study (2019), quantitative PCR (qPCR) was employed as tool for assessing the degradation of the samples. The employment of the Human Quantifiler Kit showed that the median loss of DNA ranged from 17.8% to 66.6% in groups #1-#5 while it was 85.0% in group #6. However, it is likely that these values represent an underestimation due to the shortness of the qPCR probe (62 bp). Noteworthy, the DNA loss was statistically significant in each of the six groups (p values ≤ 0.0167). Thus, in agreement with the data on spontaneous DNA decay, no forensic DNA sample should be stored in water for long term periods. In conclusion, the results of this technical note warn against the use of water for this purpose.

The use of a microwave-assisted solvent extraction coupled with HPLC-UV/PAD to assess the quality of Marrubium vulgare L. (white horehound) herbal raw material

INTRODUCTION

Marrubium vulgare is a herbal remedy presents in several European Pharmacopoeias and commonly marketed as white horehound. The chemotaxonomic marker of Marrubium genus is marrubiin and its content may change in response to biotic and abiotic stress.

OBJECTIVE

Development of a microwave-assisted solvent extraction (MASE) methodology suitable for exhaustively extracting marrubiin from M. vulgare leaves, easily applicable to large sets of samples. Evaluation of the influence of copper(II) on marrubiin production.

MATERIAL AND METHODS

M. vulgare leaves were dried, extracted exploiting MASE and analysed via high-performance liquid chromatography ultraviolet photodiode array detection (HPLC-UV/PAD) system. A design of experiments approach was adopted to select the best extraction conditions. Extraction parameters (solvent composition, extraction time and temperature), were studied applying two full factorial experimental designs in a sequential approach. To analyse samples, a rapid HPLC-UV/PAD method was set up.

RESULTS

The best results in terms of marrubiin extraction yield were obtained extracting samples at 120°C with 100% ethanol, for 15 min (3 × 5 min microwave cycles). The developed methodology was successfully applied to matrices grown in Greenhouse conditions and under stress induced by copper(II), selected as model agent for abiotic stress. Progressively decreasing production of marrubiin was evidenced in connection with treatment with 80, 200 and 300 mg/L copper sulphate.

CONCLUSION

An efficient methodology for the extraction and determination of the amount of marrubiin in large sets of samples of M. vulgare plants was developed. Results demonstrated that marrubiin is an easily detectable marker useful for evaluating M. vulgare reaction to stress.

Monitoring of Air-Dispersed Formaldehyde and Carbonyl Compounds as Vapors and Adsorbed on Particulate Matter by Denuder-Filter Sampling and Gas Chromatographic Analysis

Carbonyl compounds (CCs) are products present both as vapors and as condensed species adsorbed on the carbonaceous particle matter dispersed in the air of urban areas, due to vehicular traffic and human activities. Chronic exposure to CCs is a potential health risk given the toxicity of these chemicals. The present study reports on the measurement of the concentrations of 14 CCs in air as vapors and 2.5 µm fraction PM by the ENVINT GAS08/16 gas/aerosol sampler, a serial sampler that uses annular denuder, as sampling device. The 14 CCs were derivatized during sampling prior to gas-chromatographic separation and multiple detection by mass spectrometry, nitrogen-phosphorus thermionic, electron capture detection. Outdoor air multiple samples were collected in four locations in the urban area of Florence. The results evidenced that formaldehyde, acetaldehyde, and acetone were the more abundant CCs in the studied areas. The data collected was discussed considering the particle to vapor ratio of each CC found. The CCs pollution picture obtained was tentatively related to the nature and intensity of the traffic transiting by the sampling sites. This approach allowed to determine 14 CCs in both concentrated and diluted samples and is proposed as a tool for investigating outdoor and indoor pollution.

Development of an integrated chromatographic system for ω-transaminase-IMER characterization useful for flow-chemistry applications

An integrated chromatographic system was developed to rapidly investigate the biocatalytic properties of ω-transaminases useful for the synthesis of chiral amines. ATA-117, an (R)-selective ω-transaminase was selected as a proof of concept. The enzyme was purified and covalently immobilized on an epoxy monolithic silica support to create an immobilized enzyme reactor (IMER). Reactor efficiency was evaluated in the conversion of a model substrate. The IMER was coupled through a switching valve to an achiral analytical column for separation and quantitation of the transamination products. The best conditions of the transaminase-catalyzed bioconversion were optimized by a design of experiments (DoE) approach. The production of (R)-1-(4-methoxyphenyl)propan-2-amine and (R)-1-methyl-3-phenylpropylamine, intermediates for the synthesis of the bronchodilator formoterol and the antihypertensive dilevalol respectively, was achieved in the presence of different amino donors. The enantiomeric excess (ee) was determined off-line by developing a derivatization procedure using Nα-(2,4-dinitro-5-fluorophenyl)-L-alaninamide reagent. The most satisfactory conversion yields were 60% for (R)-1-(4-methoxyphenyl)propan-2-amine and 29% for (R)-1-methyl-3-phenylpropylamine, using isopropylamine as amino donor. The enantiomeric excess of the reactions were 84%_R and 99%_R, respectively.

Pilot Production of Mesenchymal Stem/Stromal Freeze-Dried Secretome for Cell-Free Regenerative Nanomedicine: A Validated GMP-Compliant Process

In this paper, a pilot production process for mesenchymal stem/stromal freeze-dried secretome was performed in a validated good manufacturing practice (GMP)-compliant cell factory. Secretome was purified from culture supernatants by ultrafiltration, added to cryoprotectant, lyophilized and characterized. We obtained a freeze-dried, "ready-off-the-shelf" and free soluble powder containing extracellular vesicles and proteins. In the freeze-dried product, a not-aggregated population of extracellular vesicles was detected by nanoparticle tracking analysis; Fourier transform infrared spectra showed the simultaneous presence of protein and lipids, while differential scanning calorimetry demonstrated that lyophilization process successfully occurred. A proteomic characterization allowed the identification of proteins involved in immune response, response to stress, cytoskeleton and metabolism. Moreover, the product was not cytotoxic up to concentrations of 25 mg/mL (on human fibroblasts, chondrocytes and nucleus pulposus cells by MTT assay) and was blood compatible up to 150 mg/mL. Finally, at concentrations between 5 and 50 mg/mL, freeze-dried secretome showed to in vitro counteract the oxidative stress damage induced by H₂O₂ on nucleus pulposus cells by MTT assay.

Prolonged DNA hydrolysis in water: A study on DNA stability

This work provides a protocol for the in vitro production of damaged DNA samples. In particular, heat-mediated hydrolysis of the samples at 70 °C in ultrapure water was performed in 1.7 mL Eppendorf tubes sealed by Parafilm for 0-36 h. The chemical/physical features of the resulting samples are described. After normalization of the qPCR data, these were compared with those obtained from samples treated for 0-10 h in a previous study.

In vitro efficacy of silk sericin microparticles and platelet lysate for intervertebral disk regeneration

Intervertebral disk degeneration is an oxidative and inflammatory pathological condition that induces viability and functionality reduction of Nucleus Pulposus cells (NPs). Cellular therapies were previously proposed to repair and substitute the herniated disk but low proliferative index and pathological conditions of NPs dramatically reduced the efficacy of this approach. To overcome these problems we proposed, for the first time, a therapeutic system based on the association of silk sericin microparticles and platelet-derived products. Silk sericin (SS) is a bioactive protein with marked antioxidant properties, while platelet lysate (PL) and platelet poor plasma (PPP) represent a source of growth factors able to support cell viability and to promote tissue regeneration. We demonstrated that the mixture PL + PPP promoted NPs proliferation with a significant reduction of cellular doubling time. SS microparticles, alone or in combination with PPP, presented the higher ROS-scavenging activity while, SS microparticles and PL resulted as the best association able to protect NPs against oxidative stress induce by hydroxide peroxide. Based on these results, the authors are confident that, with the ever increasing need of efficacious tools for regenerative medicine purposes, SS microparticles and PL + PPP association could represent an effective approach for the development of low impact and non-invasive therapies.

Producing standard damaged DNA samples by heating: pitfalls and suggestions

Heat-mediated hydrolysis of DNA is a simple and inexpensive method for producing damaged samples in vitro. Despite heat-mediated DNA hydrolysis is being widely used in forensic and clinical validation procedures, the lack of standardized procedures makes it impossible to compare the intra and inter-laboratory outcomes of the damaging treatments. In this work, a systematic approach to heat induced DNA hydrolysis was performed at 70 °C for 0-18 h to test the role both of the hydrolysis buffer and of the experimental conditions. Specifically, a trial DNA sample, resuspended in three different media (ultrapure water, 0.1% DEPC-water and, respectively, TE) was treated both in Eppendorf tubes ("Protocol P") and in Eppendorf tubes provided with screwcaps ("Protocol S"). The results of these comparative tests were assessed by normalization of the qPCR results. DEPC-water increased the degradation of the samples up to about 100 times when compared to the ultrapure water. Conversely, the TE protected the DNA from degradation whose level was about 1700 times lower than in samples treated in ultrapure water. Even the employment of the "Protocol S" affected the level of degradation, by consistently increasing it (up to about 180 times in DEPC-water). Thus, this comparative approach showed that even seemingly apparently trivial and often underestimated parameters modify the degradation level up to 2-3 orders of magnitude. The chemical-physical reasons of these findings are discussed together with the role of potential factors such as enhanced reactivity of CO₂, ROS, NO_x and pressure, which are likely to be involved. Since the intra and inter-laboratory comparison of the outcomes of the hydrolytic procedure is the first step toward its standardization, the normalization of the qPCR data by the UV/qPCR ratio seems to be the simplest and most reliable way to allow this. Finally, the supplying (provided with the commercial qPCR kits) of a DNA sample whose degree of degradation is well documented could be helpful in ISO/IEC 17025 validation procedures and in proficiency testing.

Hydrophilic interaction chromatography in food matrices analysis: An updated review

This review focuses on the most recent papers (from 2011 to submission date in 2017) dealing with the analysis of different organic components in foods (i.e. nucleobases, nucleosides, nucleotides, uric acid, and creatinine, amino acids and related compounds, choline-related compounds and phospholipids, carbohydrates, artificial sweeteners and polyphenolic compounds), using hydrophilic interaction liquid chromatography (HILIC) combined with different detection techniques. For each compound class, the investigated food matrices are grouped per: foods of animal origin, vegetables, fruits and related products, baby food, and other matrices such as drinks and mushrooms/fungi. Furthermore, the main advantages of HILIC chromatography respect to the other commonly used techniques are discussed.

Acrylate-based poly-high internal phase emulsions for effective enzyme immobilization and activity retention: from computationally-assisted synthesis to pharmaceutical applications

PolyHIPE functional materials were chemically conjugated with a model enzyme. It retained its activity upon flow as demonstrated by the conversion of a specific substrate.

Correction: Rational design of functionalized polyacrylate-based high internal phase emulsion materials for analytical and biomedical uses

Correction for ‘Rational design of functionalized polyacrylate-based high internal phase emulsion materials for analytical and biomedical uses’ by Gloria Brusotti et al., Polym. Chem., 2016, DOI: 10.1039/c6py01992g.

Rational design of functionalized polyacrylate-based high internal phase emulsion materials for analytical and biomedical uses

Functional polyacrylate-based materials rationally designed by high internal phase emulsion (polyHIPE) are reported.

The molecular characterization of a depurinated trial DNA sample can be a model to understand the reliability of the results in forensic genetics

The role of DNA damage in PCR processivity/fidelity is a relevant topic in molecular investigation of aged/forensic samples. In order to reproduce one of the most common lesions occurring in postmortem tissues, a new protocol based on aqueous hydrolysis of the DNA was developed in vitro. Twenty-five forensic laboratories were then provided with 3.0 μg of a trial sample (TS) exhibiting, in mean, the loss of 1 base of 20, and a molecular weight below 300 bp. Each participating laboratory could freely choose any combination of methods, leading to the quantification and to the definition of the STR profile of the TS, through the documentation of each step of the analytical approaches selected. The results of the TS quantification by qPCR showed significant differences in the amount of DNA recorded by the participating laboratories using different commercial kits. These data show that only DNA quantification "relative" to the used kit (probe) is possible, being the "absolute" amount of DNA inversely related to the length of the target region (r(2) = 0.891). In addition, our results indicate that the absence of a shared stable and certified reference quantitative standard is also likely involved. STR profiling was carried out selecting five different commercial kits and amplifying the TS for a total number of 212 multiplex PCRs, thus representing an interesting overview of the different analytical protocols used by the participating laboratories. Nine laboratories decided to characterize the TS using a single kit, with a number of amplifications varying from 2 to 12, obtaining only partial STR profiles. Most of the participants determined partial or full profiles using a combination of two or more kits, and a number of amplifications varying from 2 to 27. The performance of each laboratory was described in terms of number of correctly characterized loci, dropped-out markers, unreliable genotypes, and incorrect results. The incidence of unreliable and incorrect genotypes was found to be higher for participants carrying out a limited number of amplifications, insufficient to define the correct genotypes from damaged DNA samples such as the TS. Finally, from a dataset containing about 4500 amplicons, the frequency of PCR artifacts (allele dropout, allele drop-in, and allelic imbalance) was calculated for each kit showing that the new chemistry of the kits is not able to overcome the concern of template-related factors. The results of this collaborative exercise emphasize the advantages of using a standardized degraded DNA sample in the definition of which analytical parameters are critical for the outcome of the STR profiles.

Characterization of intact neo-glycoproteins by hydrophilic interaction liquid chromatography

In this study, an HPLC HILIC-UV method was developed for the analysis of intact neo-glycoproteins. During method development the experimental conditions evaluated involved different HILIC columns (TSKgel Amide-80 and ZIC-pHILIC), and water-acetonitrile mixtures containing various types of acids and salts. The final selected method was based on a TSKgel Amide-80 column and a mobile phase composed of acetonitrile and water both containing 10 mM HClO4. The influence of temperature and sample preparation on the chromatographic performances of the HILIC method was also investigated. The method was applied to the separation of neo-glycoproteins prepared starting from the model protein RNase A by chemical conjugation of different glycans. Using the method here reported it was possible to monitor by UV detection the glycosylation reaction and assess the distribution of neo-glycoprotein isoforms without laborious sample workup prior to analysis.

Assessment of DNA damage by micellar electrokinetic chromatography

A simple and inexpensive MEKC method, which is able to assess base damage within DNA samples, is illustrated. After heat-acid hydrolysis of the DNA samples, both the percentage of each canonical DNA base and the relative amount of uncanonical DNA bases can be measured. This method is useful for an evaluation of the integrity of PCR templates used in several fields of investigation.

Effect of in vitro digestion on free α-dicarbonyl compounds in balsamic vinegars

We investigated the influence of an in vitro simulated digestion process on the content of the free α-dicarbonyl compounds most frequently found in food. A Glyoxal (GO), methylglyoxal (MGO), and diacetyl (DA) aqueous standard mixture and 2 brands of balsamic vinegar were analyzed before and after exposure to digestive enzymes. A strong matrix effect required adoption of validated RP-HPLC-DAD standard addition methods. The results showed that the digestive enzymes markedly alter the concentrations of the exogenous free α-dicarbonyl compounds ingested with food; the extent of such changes varied with the α-dicarbonyl compound itself and the diet components, which determined important but different food matrix effects also during digestion. The data also indicate that digestion can reduce the bioavailability of the toxic α-dicarbonyl compounds ingested with food. However, no firm conclusions can be drawn about a putative positive influence of digestion on the toxic potential of dietary α-dicarbonyl compounds, because their reaction in the presence of digestive enzymes likely gives rise to advanced glycation end products, which are involved in the development of chronic diseases.

Identification of phenolic constituents in Cichorium endivia var. crispum and var. latifolium salads by high-performance liquid chromatography with diode array detection and electrospray ioniziation tandem mass spectrometry

Chicory is a widely consumed vegetable and a source of phenolic compounds. Phenolic acid and flavonoid derivatives were identified in Cichorium endivia var. crispum and var. latifolium and fully characterized using complementary information from two different high-performance liquid chromatography detectors, diode array and mass spectrometer, in positive and negative modes. We describe about 40 phenolic compounds, some of which have never previously been reported in these plants, such as hydroxycinnamic acid derivatives (i.e., different mono- and dicaffeoylquinic acid isomers) and mono- and diglycosides of quercetin, kaempferol, and myricetin (differing also by the glycosylation site). These data provide a contribution to a more exhaustive identification of phenolic compounds in C. endivia vegetables.

Experimental design applied to the optimization of microwave-assisted DNA hydrolysis

The assessment of the integrity of the DNA primary structure and the identification of canonical and modified bases are useful tools in medical, pharmaceutical, and forensic applications. In this article we report on the first microwave-assisted hydrolyses of deoxyribonucleoside-triphosphates (dNTPs) and human DNA using "Design of Experiments" methodology. We use hydrophilic interaction chromatography (HILIC) and UV detection at 260 nm for the determination of purinic and pyrimidinic bases at levels of 0.5 μM. We use a ZIC-HILIC 150mm × 2.1 mm i.d., 5 μm particle size column and ammonium formate buffers in acetonitrile for gradient separation of the analytes. We then compare the final concentrations of Thymine, Adenine, Cytosine, and Guanine with the nominal amounts of such bases in the dNTPs and DNA submitted to hydrolysis. After optimization of the hydrolysis (11.5 min, 0.15 M aqueous HCl, 150 °C), the method turns out to be suitable for the determination of products released from quantities of human DNA as low as 500 ng with precision (RSD<10%) and accuracy (REC 97-104%). These results confirm that the kinetics of the release of the bases depends on their molecular structure and show that the concentration of the substrate plays a relevant role. We conclude with a discussion of the method and a comparison to the methods described in previous studies.