High-precision Helicobacter pylori infection diagnosis using a dual-element multimodal gas sensor array.

Helicobacter pylori (H. pylori) is a globally widespread bacterial infection. Early diagnosis of this infection is vital for public and individual health. Prevalent diagnosis methods like the isotope 13C or 14C labelled urea breath test (UBT) are not convenient and may do harm to the human body. The use of cross-response gas sensor arrays (GSAs) is an alternative way for label-free detection of metabolite changes in exhaled breath (EB). However, conventional GSAs are complex to prepare, lack reliability, and fail to discriminate subtle changes in EB due to the use of numerous sensing elements and single dimensional signal. This work presents a dual-element multimodal GSA empowered with multimodal sensing signals including conductance (G), capacitance (C), and dissipation factor (DF) to improve the ability for gas recognition and H. pylori-infection diagnosis. Sensitized by poly(diallyldimethylammonium chloride) (PDDA) and the metal-organic framework material NH2-UiO66, the dual-element graphene oxide (GO)-composite GSAs exhibited a high specific surface area and abundant adsorption sites, resulting in high sensitivity, repeatability, and fast response/recovery speed in all three signals. The multimodal sensing signals with rich sensing features allowed the GSA to detect various physicochemical properties of gas analytes, such as charge transfer and polarization ability, enhancing the sensing capabilities for gas discrimination. The dual-element GSA could differentiate different typical standard gases and non-dehumidified EB samples, demonstrating the advantages in EB analysis. In a case-control clinical study on 52 clinical EB samples, the diagnosis model based on the multimodal GSA achieved an accuracy of 94.1%, a sensitivity of 100%, and a specificity of 90.9% for diagnosing H. pylori infection, offering a promising strategy for developing an accurate, non-invasive and label-free method for disease diagnosis.

A Prototype of Graphene E-Nose for Exhaled Breath Detection and Label-Free Diagnosis of Helicobacter Pylori Infection.

Helicobacter pylori (HP), a common microanaerobic bacteria that lives in the human mouth and stomach, is reported to infect ≈50% of the global population. The current diagnostic methods for HP are either invasive, time-consuming, or harmful. Therefore, a noninvasive and label-free HP diagnostic method needs to be developed urgently. Herein, reduced graphene oxide (rGO) is composited with different metal-based materials to construct a graphene-based electronic nose (e-nose), which exhibits excellent sensitivity and cross-reactive response to several gases in exhaled breath (EB). Principal component analysis (PCA) shows that four typical types of gases in EB can be well discriminated. Additionally, the potential of the e-nose in label-free detection of HP infection is demonstrated through the measurement and analysis of EB samples. Furthermore, a prototype of an e-nose device is designed and constructed for automatic EB detection and HP diagnosis. The accuracy of the prototype machine integrated with the graphene-based e-nose can reach 92% and 91% in the training and validation sets, respectively. These results demonstrate that the highly sensitive graphene-based e-nose has great potential for the label-free diagnosis of HP and may become a novel tool for non-invasive disease screening and diagnosis.

Perfluorinated polymer modified vertical silicon nanowires as ultra low noise laser desorption ionization substrate for salivary metabolites profiling.

Metabolites in the body fluid are becoming a rich source of disease biomarkers. Developing an effective and high throughput detection and analysis platform of metabolites is of great importance for potential biomarker discovery and validation. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has been successfully applied in rapid biomolecules detection in large scale. However, non-negligible background interference in low molecule-weight region still constitutes a main challenge even though various nanomaterials have been developed as an alternative to traditional organic matrix. In this work, a novel composite chip, silicon nanowires loaded with fluorinated ethylene propylene (FEP@SiNWs) was fabricated. It can serve as an excellent substrate for nanostructure-initiator mass spectrometry (NIMS) detection with ultra-low background noise in low molecular weight region (<500 Da). Ion desorption efficiency and internal energy transfer of FEP@SiNWs were studied using benzylpyridinium salt and tetraphenylboron salt as thermometer chemicals. The results indicated that a non-thermal desorption mechanism might be involved in the LDI process on FEP@SiNWs. Owing to the higher LDI efficiency and low background interference of this novel substrate, the metabolic fingerprint of complex bio-fluids, such as human saliva, can be sensitively and stably acquired. As a proof of concept, FEP@SiNWs chip was successfully used in the detection of salivary metabolites. With the assistance of multivariate analysis, 22 metabolic candidates (p < 0.05) which can discriminate type 2 diabetes mellitus (2-DM) and healthy volunteers were found and identified. The role of these feature metabolites in the metabolic pathway involved in 2-DM was confirmed by literature mining. This work demonstrates that FEP@SiNWs-based NIMS might be served as an efficient and high throughput platform for metabolic biomarker exploration and clinical diagnosis.

[Mucoadhesive buccal films of tramadol for effective pain management]. / Filmes bucais mucoadesivos de tramadol para o controle eficaz da dor.

BACKGROUND AND OBJECTIVES: Tramadol hydrochloride is a centrally-acting synthetic opioid analgesic binding to specific opioid receptors. It is used in the management of chronic pain and is recommended as first line drug in the treatment of postoperative or orthopedic injury induced acute pain. The present work is designed to prepare and evaluate mucoadhesive buccal film of tramadol hydrochloride as a novel form of prolonged analgesia for patients with orthopedic injuries. METHODS: Buccal films of tramadol hydrochloride were prepared by solvent casting method. The prepared films were evaluated for the various evaluation parameters like thickness, surface pH, weight uniformity, content uniformity, folding endurance, swelling index, in vitro drug release study, in vitro test for mucoadhesion and in vivo studies (primary mucosal irritancy test and analgesic activity). RESULTS: All the formulations exhibited good results for physicochemical characterizations. In in vitro drug release study the films exhibited controlled release more than 12hours. The formulation BFT2 (containing chitosan and PVP K-90) showed no irritant effect on buccal mucosa and elicit the significant in vivo analgesic activity with 57.14% analgesia against that of standard (61.04%). It was concluded that the mucoadhesive films of tramadol hydrochloride can be effectively used to alleviate the severe pain of orthopedic injuries with prompt onset and prolonged action.

Storage of serum peptide information in nanoporous silicon microparticles.

Serum peptides are becoming a rich source of disease biomarkers, therefore, preserving serum peptide information after sample collection is of great importance. This work demonstrates that nanoporous silicon microparticles can be successfully applied in the storage of peptide information.

Use of a porous silicon-gold plasmonic nanostructure to enhance serum peptide signals in MALDI-TOF analysis.

Small peptides in serum are potential biomarkers for the diagnosis of cancer and other diseases. The identification of peptide biomarkers in human plasma/serum has become an area of high interest in medical research. However, the direct analysis of peptides in serum samples using mass spectrometry is challenging due to the low concentration of peptides and the high abundance of high-molecular-weight proteins in serum, the latter of which causes severe signal suppression. Herein, we reported that porous semiconductor-noble metal hybrid nanostructures can both eliminate the interference from large proteins in serum samples and significantly enhance the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) yields of peptides captured on the nanostructure. Serum peptide fingerprints with high fidelity can be acquired rapidly, and successful discrimination of colorectal cancer patients based on peptide fingerprints is demonstrated.

Mucoadhesive buccal films of tramadol for effective pain management / Filmes bucais mucoadesivos de tramadol para o controle eficaz da dor

Abstract Background and objectives: Tramadol hydrochloride is a centrally-acting synthetic opioid analgesic binding to specific opioid receptors. It is used in the management of chronic pain and is recommended as first line drug in the treatment of postoperative or orthopedic injury induced acute pain. The present work is designed to prepare and evaluate mucoadhesive buccal film of tramadol hydrochloride as a novel form of prolonged analgesia for patients with orthopedic injuries. Methods: Buccal films of tramadol hydrochloride were prepared by solvent casting method. The prepared films were evaluated for the various evaluation parameters like thickness, surface pH, weight uniformity, content uniformity, folding endurance, swelling index, in vitro drug release study, in vitro test for mucoadhesion and in vivo studies (primary mucosal irritancy test and analgesic activity). Results: All the formulations exhibited good results for physicochemical characterizations. In in vitro drug release study the films exhibited controlled release more than 12 hours. The formulation BFT2 (containing chitosan and PVP K-90) showed no irritant effect on buccal mucosa and elicit the significant in vivo analgesic activity with 57.14% analgesia against that of standard (61.04%). It was concluded that the mucoadhesive films of tramadol hydrochloride can be effectively used to alleviate the severe pain of orthopedic injuries with prompt onset and prolonged action.

Resumo Justificativa e objetivos: O cloridrato de tramadol é um analgésico opioide de ação central que se liga a receptores opioides específicos. É usado no tratamento de dor crônica e recomendado como fármaco de primeira linha para o tratamento no pós-operatório ou em dor aguda induzida por lesão ortopédica. O presente estudo visa a preparar e avaliar o filme bucal mucoadesivo de cloridrato de tramadol como uma nova forma de analgesia prolongada para pacientes com lesões ortopédicas. Método: Filmes bucais de cloridrato de tramadol foram preparados pelo método de evaporação de solvente. Os filmes preparados foram avaliados para os vários parâmetros de avaliação, como espessura, pH da superfície, uniformidade do peso, uniformidade do conteúdo, resistência a dobras, índice de intumescimento, estudo de liberação da droga in vitro, teste in vitro para mucoadesão e estudos in vivo (teste de irritação da mucosa primária e atividade analgésica). Resultados: Todas as formulações apresentaram bons resultados para caracterizações físico-químicas. Em estudo de libertação de droga in vitro, os filmes exibiram liberação controlada por mais de 12 horas. A formulação de BFT2 (com quitosana e PVP K-90) não mostrou efeito irritante sobre a mucosa bucal e provocou uma atividade analgésica significativa in vivo com 57,14% de analgesia versus a do padrão (61,04%). Concluiu-se que os filmes mucoadesivos de cloridrato de tramadol podem ser usados eficazmente para aliviar a dor intensa de lesões ortopédicas com início rápido e ação prolongada.