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The aim of this chapter is to provide a short overview of CE coupled to MS focusing on historical achievements, principles, and some selected applications.

In the present study separation of enantiomers of some chiral neutral and weakly acidic analytes was investigated on the chiral stationary phase (CSP) made by covalent immobilization of amylose tris(3-chloro-5-methylphenylcarbamate) onto silica in nano-liquid chromatography (nano-LC) and capillary electrochromatography (CEC) in acetonitrile and aqueous acetonitrile. Few comparisons were made also between the enantioseparations in nano-LC and high-performance liquid chromatography (HPLC) with the chiral column of 4.6 x 250 mm dimension. Slightly better separation of enantiomers was observed in HPLC mode compared to nano-LC mode. It was shown that in the capillary columns packed with the CSP containing about 20% (w/w) of a covalently immobilized neutral chiral selector, amylose tris(3-chloro-5-methylphenylcarbamate), sufficient electroosmotic flow has been generated and enantioseparations with reasonable analysis time were performed also in CEC mode. It was shown once again that CEC offers a clear advantage over nano-LC from the viewpoint of plate numbers and peak resolution. (C) 2019 Elsevier B.V. All rights reserved.

When splinting multiple implants passive fit of the framework should be achieved to avoid excessive force distribution on the implants. Recently, a protocol was suggested for immediate loading of multiple implants by welding a titanium bar to implant abutments directly in the oral cavity so as to create a customized, precise and passive metal-reinforced provisional restoration. The intraoral welding technique subsequently proves to be a successful option in the full-arch immediate restorations of the mandible and maxilla. The aim of this article is to present a case report in which a new prosthetic approach, using trans-mucosal implants, is described. Dental implants are instantly loaded with a provisional prosthesis supported by an intraoral welded titanium framework to obtain a precise passive fit of the immediate loaded prosthesis.

The aim of the present study is to define the optimal thread form and why the macroscopic shape of the dental intra-osseous implant interacts with the biological environment thus conditioning its lifespan and long-term success.

Nanoliquid chromatography (nano-LC) is a recently developed miniaturized chromatographic technique offering some advantages over conventional high-performance liquid chromatography. It is applied to the separation and analysis of a large number of compounds of interest in various application fields such as proteomics, pharmaceutical, environment, chiral, food, etc. The main features are discussed in this chapter. The instrumentation usually employed in nano-LC is illustrated by considering problems that arise when using low mobile phase flow rates and capillary columns with internal diameter < 100 ?m. The second part of the chapter presents some selected applications published during 2011-16.

This chapter presents the main features of nano-liquid chromatography (nano-LC), its advantages over conventional LC techniques, and some selected applications published in the last 5 years. Nano-LC is the miniaturization of HPLC where the analytes separation takes place into capillary columns of thin diameter (

In the present study, an attempt was made to achieve separation of enantiomers within a minute in nano-LC and CEC. In order to achieve this goal several parameters were optimized from the viewpoint of the property of chiral analytes, concentration of the chiral selector in the packing material, capillary dimensions, and separation mode. The enantiomers of several of the applied chiral sulfoxides could be resolved with the analysis time

The aim of this study is to determine in an experimental way through mechanical tests the static, fatigue and torque resistance of two types of implant/abutment connectors with diameters of 3.4–5.2 mm.

It is generally accepted that the mandible (especially in the interforaminal region) has better bone quality than the maxilla, and this fact is probably the reason why several reports are available regarding implants inserted into the mandible. Since no report is available on a new type of implants, a retrospective study was performed. A total of 185 two-piece implants (FMD srl, Rome, Italy) were inserted in mandible, 102 in female and 83 in males. The median age was 58 ± 13 (min-max 25–80 years). Implants replaced 14 incisors, 7 cuspids, 49 premolars and 115 molars. Implant' length was x ≤ 10 mm, 10,30 ≤ x ≤ 12.30, equal to 13 mm and x ≥14 mm in 80, 90,13 and 2 cases, respectively. Implant' diameter was narrower than 3.5 mm, equal to 3.8 mm and wider than 4.0 mm in 25, 17,143 cases, respectively. There were 36,41,106 and 2 Elisir, I-fix, Shiner, and Storm implant types, respectively. One implant was lost, survival rate = 98.15%. Among the studies variables immediate loaded implants on single tooth rehabilitations (p=0.017) have a worse clinical outcome. Then peri-implant bone resorption (i.e. delta IAJ) was used to investigate SCR. Among the remaining 184 implants, 20 fixtures have a crestal bone resorption greater than 1.5 mm (SCR = 89.13). Statistical analysis demonstrated signifiance only for surgeon (p=0.001). In conclusion FMD implants are reliable devices for oral rehabilitation with a very high SCR and SVR.

Nowadays, research on orthopedic and dental implants is focused on titanium alloys due to their appropriated mechanical properties and corrosion resistance in the body environment. Another important aspect to be investigated is their surface topography, which is very important to osseointegration. The aim of this study was to assess dental pulp stem cells response to different titanium surface topography modified. Mesenchymal stem cell marker ENG was significantly decreased in stem cells cultivated in modified titanium surface respect to machined titanium surface, indicating the differentiation effect of this biomaterial on stem cells. The obtained results can be relevant to better understand the molecular mechanism of bone regeneration and as a model for comparing other materials with similar clinical effects.

After microbial invasion and tissue damage, a set of cytokines, including interleukin-1α (IL-1α), IL-1β, IL-6, IL-18 and tumor necrosis factor-α (TNF-α), and microbial and endogenous molecules named pathogen-associated molecular pattern (PAMPs) and damage-associated molecular pattern (DAMPs), are released from activated leukocytes and dead cells and bind to immune receptors to induce the innate and adaptive response. The intracellular signals induced by the multiprotein complex formed by the Toll-like receptors/IL-1 receptors (TLRs), NOD-like receptors (NLRs) and tumor necrosis factor-α receptors (TNFRs) and their ligands and downstream effectors lead to the activation of NF-κB (NFkappaB) and the interferon regulatory factor (IRF) transcription factors and thereby the synthesis of pro- and anti-inflammatory genes as well as pro- and anti-cell death genes. Depending on cell-intrinsic and extrinsic biochemical events elicited by an inflammatory response, the cells die via apoptosis, necrosis, pyroptosis or autophagy cell death program. This article resumes our current understanding of these processes and how they influence inflammation.

A rapid method for the quantification of five ribonucleotides 5- monophophates (adenosine, cytidine, guanosine, inosine, uridine, 5-monophosphate), in infant formula, has been proposed using nano-LC. To separate the studied compounds, capillary columns packed with different C18-based stationary phases were investigated. All the columns tested were laboratory prepared. The experiments were performed in ion-pairing RP chromatographic mode using tetrabutylammonium hydroxide as ion-pairing reagent. The method was developed using a core-shell XB-C18 capillary column with a mobile phase consisting of 5% v/v methanol and 95% v/v 100 mM ammonium formate, pH 8, containing 20 mM tetrabutylammonium hydroxide. All compounds were baseline resolved in less than 5 min with a flow rate of 500 nL/min in isocratic elution mode. Nucleotides were detected at 260 nm. Analytical validation parameters were evaluated. The RSD values for intraday and interday repeatability for retention time and peak area were

In the last decade, several investigators have reported that autologous and homologous fresh frozen bones (FFB) are effective materials to restore alveolar ridges previous to insert dental implants. Here we reported a comparative study between spiral implants inserted in FFB and native bone to evaluate their clinical outcome. Patients were grafted and spiral implants were inserted in the same surgical time. Several variables (patient, grafts, anatomic site, implant, prosthetic restoration) were investigated. Implant’ failure and peri-implant bone resorption were considered as predictor of clinical outcome. 51 implants were inserted in 12 patients. Implants were inserted to replace 8 incisors, 4 cuspids, 18 premolars and 21 molars. The mean follow-up was 14 months. No implant was lost. Peri-implant bone resorption (i.e. success rate) was used as predictor of clinical outcome but Kaplan Meier algorithm demonstrates that no studied variable has a statistical significant impact on clinical outcome. FFB and native bone havehigh and comparable survival and success rate. Spiral implants can be successfully inserted in native e grfted bone to performe an oral rehabilitation

Miniaturization is one of the emerging trends in modern analytical chemistry. Capillary electrophoresis (CE), capillary electrochromatography (CEC), and more recently nano-liquid chromatography (nano-LC) have been successfully miniaturized and applied to forensic drug analysis. This review will discuss the recent applications of miniaturized separation techniques for the analysis of illicit drugs and new psychoactive substances in seized materials and biological fluids. Particular attention is given to chiral discrimination of abused drugs, which is an important topic in forensic analysis.

I derivati dell’aloe hanno trovato negli ultimi anni ampio utilizzo, sia in campo cosmetico, sia in campo erboristico. In entrambi i casi si rende necessario effettuare controlli di qualità, allo scopo di prevenire possibili effetti indesiderati dovuti alla presenza di alcuni principi attivi, soprattutto di natura antrachinonica. Inoltre, è necessario poter distinguere gli estratti provenienti da aloe di diverse specie (ad esempio, Aloe vera ed Aloe del Capo), per evitare frodi merceologiche. Scopo di questo studio è, quindi, lo sviluppo di un metodo analitico per la separazione e la determinazione simultanea dei principali composti antrachinonici dell’aloe, come ad esempio le forme isomeriche di aloina, aloeresina, 5-idrossialoina, 7-idrossialoina e aloinoside. Il metodo sviluppato è basato sull’HPLC con rivelazione a serie di fotodiodi (DAD); utilizza una colonna a fase inversa C8 ed una fase mobile composta da acqua e metanolo. Le analisi su estratti vegetali di aloe sono effettuate dopo purificazione dei campioni mediante cromatografia preparativa su colonna di gel di silice. Un’aliquota di estratto polverizzato è applicata alla colonna e si raccolgono le frazioni ottenute dall’eluizione con etere di petrolio / etile acetato. Le frazioni sono poi oppportunamente diluite ed iniettate nel sistema HPLC. È stato possibile distinguere campioni provenienti da diverse specie di aloe in base alla presenza di composti caratteristici. Il metodo analitico è attualmente in fase di convalida.

A method has been developed for the analysis of the antidepressant drug sertraline together with its main metabolite N-desmethylsertraline in human plasma. It is based on capillary electrophoresis with laser-induced fluorescence (LIF) detection (lambda = 488 nm). A solid phase extraction procedure is employed for biological sample pre-treatment, followed by a derivatisation step with fluorescein isothiocyanate; reboxetine was the internal standard. The effect of cyclodextrin, acetone and N-methyl-glucamine as constituents of the background electrolyte for analyte separation was investigated. The final background electrolyte consisted of 20 mM carbonate buffer, pH 9.0, with 2.5 mM heptakis(2,6-di-O-methyl)-beta-cyclodextrin, 50 mM N-methylglucamine and 20%, v/v acetone. With 30 kV applied voltage the electrophoretic run is completed in 7.5 min. Linearity was observed in the plasma concentration range from 3.0 to 500 ng/mL for sertraline and 4.0 to 500 ng/mL for desmethylsertraline. Extraction yield was >97.1%, precision - expressed as RSD% - was 95.6%. Due to its sensitivity and selectivity the method was suited for the analysis of plasma samples from patients undergoing therapy with sertraline.

Amisulpride (4-amino-N-[(1-ethyl-2-pyrrolidinyl)methyl]-5-(ethylsulfonyl)-2-methoxy-benzamide) is an atypical antipsychotic drug which is administered at low doses (50 mg/day) for the treatment of dysthymia and negative symptoms of schizophrenia, while at higher doses (400-1200 mg/day) it is efficacious in reducing the positive symptoms of schizophrenia. It has a chiral benzamidic structure and exerts its action by interacting with the D2 and D3 mesolimbic receptors. The main side effects of the drug are, hyperkinesia, anxiety and insomnia; minor extrapiramidal symptoms have been reported . Amisulpride is administered as the racemate, in the form of oral tablets (Deniban®, Solian® or Sulamid®), even if binding studies showed that the S(-) enantiomer is several times more potent than the R(+) enantiomer. However, only one HPLC method is currently available in the literature for the enantioselective determination of Amisulpride in biological fluids . The aim of this work is the development of a method based on capillary electrophoresis with diode-array detection for the enantiomeric separation of Amisulpride and its analysis in commercially available tablets. An uncoated fused silica capillary (effective length 8.5 cm, internal diameter 50 µm) was used, injecting the samples by pressure at the cathodic side. The effect of several parameters such as pH and buffer composition, as well as the applied voltage and the capillary temperature were investigated in order to obtain a complete separation in the shortest analysis time. The applied voltage was +15 kV, with the capillary thermostatted at 20°C and the detector set at 227 nm. Negatively charged beta-cyclodextrin was added to the BGE in order to separate Amisulpride enantiomers; the BGE consisted of a 10 mM pH 3.5 citrate buffer, containing beta-cyclodextrin sulfated (0.22%, w/v), which was sufficient to determine anodic migration of both enantiomers. Under these conditions a complete separation of Amisulpride enantiomers was obtained within a 10 min electrophoretic run, using Lamotrigine as the internal standard. A very simple procedure, consisting of a single extraction with MeOH, allows to quantitatively extract Amisulpride from the formulation. The method has been fully validated in terms of linearity (linearity range from 2.5 to 25 µg/mL), precision and accuracy (recovery percentage always ≥ 90%). Finally, it has been successfully applied to the quality control of commercially available tablets (Deniban®) containing racemic Amisulpride.

Vancomycin is a glicopeptide antibiotic, isolated from the soil microorganism Streptomyces orientalis, which is used for the treatment of severe infections caused by Gram-positive organisms; Vancomycin is administred in parenteral form for the treatment of endocarditis and other severe infections and in oral form for the treatment of colon infections. New formulations are in progress to obtain a controlled release of the drug in the colon site, in order to use the antibiotic for the treatment of specific intestinal patologies. The aim of this work is the development of a quick analytical method for the quality control of commercial oral capsules, vials for intravenous injections and innovative microparticles. The method is based on capillary zone electrophoresis. A 3D-CE Agilent instrument equipped with a diode-array detector was used; fused silica capillaries, with a total capillary length of 48.5 cm and an effective length of 8.5 cm (100 µm internal diameter) were used. The BGE consisted of a 12.5 mM phosphate buffer, whose pH was adjusted to 2.5 using sodium hydroxide. The applied voltage was –20 kV, the detection wavelenght 210 nm, with the capillary thermostatted at 25°C. The samples were diluted in water and injected by pressure (30 mbar for 3 s) from the anodic side of the capillary. An electrophoretic run is completed within 3.0 minutes, using Triprolidine as the internal standard. Good linearity was found in the Vancomycin concentration range from 500 ng/mL to 5 µg/mL with satisfactory precision. After validation, the method was applied to the analysis of commercial capsules, vials and innovative microparticles; preliminary investigations gave satisfactory results.

Mirtazapine (MIR) and two of its main metabolites, namely, 8-hydroxymirtazapine and N-desmethylmirtazapine, were separated in totheir enantiomers by nanoLC in a laboratory-made fused-silica capillary column (75 µm ID) packed with a vancomycin modified silica stationary phase. The simultaneous separation of the three couples of the studied enantiomers was achieved in less than 33 min, using an experimentally optimized mobile phase delivered in the isocratic mode. Optimization of the mobile phase composition was achieved by testing the influence of the buffer pH and concentration, the water concentration, the organic modifier type and concentration, and on the retention and resolution of the analytes. The optimum mobile-phase composition contained 500 mM ammonium acetate pH 4.5/water/MeOH/MeCN, 1:14:40:45 v/v/v/v. Using a UV detector at 205 nm, the method was validated studying several experimental parameters such as LOD and LOQ, intraday and interday repeatability, and linearity. Good results were achieved: LOD and LOQ were in the range 5–15 and 10–40 µg/mL, respectively (the highest value was obtained for the DEMIR enantiomers); correlation coefficients, 0.9993–0.9999; the intraday and interday precision was acceptable (RSD < 2%) using an internal standard. The method was tested for the separation of the studied enantiomers in an extracted (solid-phase) serum sample spiked with standard racemic mixture of MIR and its two metabolites. Finally, the nanoLC system was connected to a mass spectrometer through a nanoelectrospray interface and the MS, MS2, and MS3 spectra were acquired showing the potential of the system used for characterization and identification of the separated analytes.