Jose M Costa-Fernandez

• Ph.D. in Chemistry. Analytical Chemistry.
• University of Oviedo

A novel and simple methodology is introduced that allows accurate and highly sensitive detection of microRNAs (miRNAs), taking advantage of an amplification strategy based on multicomponent nucleic acid enzymes (MNAzymes), combined with a fluorescence resonance energy transfer (FRET) phenomenon. For this purpose, a fluorescent dye (FAM) has been se...

There is a growing need for portable and handheld instruments that can facilitate rapid, efficient on-site screening for food contaminants. Several alternatives exist for developing analytical methods to meet these needs; however, they often rely on expensive and powerful laboratory equipment. Recent developments in chemical analysis focus on the u...

A multi-modal metrological approach for the quantification of lanthanide doped carbon dots (Eu and Yb) uptaken by HeLa cells using sc-ICP-ToF-MS.

Food safety control is a key issue in the food and agriculture industries. For such purposes, developing miniaturized analytical methods is critical for enabling the rapid and sensitive detection of food supplements, allergens, and pollutants. Here, a novel bioanalytical methodology based on DNA-functionalized gold nanoparticles (AuNPs) and colorim...

The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader...

One of the most consumed foods is milk and milk products, and guaranteeing the suitability of these products is one of the major concerns in our society. This has led to the development of numerous sensors to enhance quality controls in the food chain. However, this is not a simple task, because it is necessary to establish the parameters to be ana...

Nanosized UiO66 are among the most studied MOF materials. They have been extensively applied in various areas, such as catalysis, gas absorption, electrochemistry, chemical sensing, and biomedical applications. However, the preparation of stable nano-sized UiO66 for drug delivery applications is challenging because of the high tendency of UiO66 to...

A major challenge in the 21st century is the development of point-of-care diagnostic tools capable to detect and quantify disease biomarkers in a straightforward, affordable, sensitive, and specific manner. The remarkable plasmonic properties of gold nanoparticles (AuNPs) have promoted their use for development of simple methodologies for nucleic a...

Food safety and quality are the first steps in the food chain. This work reports a miniaturized, low-cost, and easy-to-use near-infrared spectroscopy (NIRS) measurement system for alfalfa quality control. This is a significant challenge for dairy farm technicians and producers who need rapid and reliable knowledge of the forage quality on their far...

MicroRNAs (miRNAs) represent a class of small noncoding RNAs that are considered a novel emerging class of disease biomarkers in a variety of afflictions. Sensitive detection of miRNA is typically achieved using hybridization-based methods coupled with genetic amplification techniques. Although their sensitivity has improved, amplification techniqu...

Food safety and quality are the first steps in the food chain. This work reports a low-cost and easy-to-use optoelectronic measurement system for improving feed chain quality and safety, based on near-infrared spectrometry (NIRS) technology. This is a significant challenge for dairy farm technicians and producers who need rapid and reliable knowled...

Photodynamic therapy (PDT) is a promising minimally invasive alternative cancer treatment that, due to fluorescent properties of the drug (photosensitizer), can be used as a theragnostic agent. The efficacy of this treatment largely relies on the successful activation of the photosensitizer with appropriate light. While certain studies demonstrate...

Herein, we introduce the first relative single-particle inductively coupled plasma mass spectrometry (spICP-MS) approach where size calibration is carried out using the target NP itself measured under different instrumental conditions without external dependence on the complex and prone-to-error determination of transport efficiency or mass flux ca...

In-depth characterization of functionalized nanomaterials is still a remaining challenge in nanobioanalytical chemistry. In this work, we propose the online coupling of Asymmetric Flow Field-Flow Fractionation (AF4) with UV/Vis, Multiangle Light Scattering (MALS) and Inductively Coupled Plasma-Tandem Mass Spectrometry (ICP-MS/MS) detectors to carry...

Potentially toxic elements (PTEs) and polycyclic aromatic hydrocarbons (PAHs) frequently coexist in soils near industrial areas and sometimes in environmental compartments directly linked to feed (forage) and food (milk) production. However, the distribution of these pollutants along the dairy farm production chain is unclear. Here, we analyzed soi...

The prolific applicability of nanomaterials has made them a common citizen in biological systems, where they interact with proteins forming a biological corona complex. These complexes drive the interaction of nanomaterials with and within the cells, bringing forward numerous potential applications in nanobiomedicine, but also arising toxicological...

Adulterations of olive oil are performed by adding seed oils to this high-quality product, which are cheaper than olive oils. Food safety controls have been established by the European Union to avoid these episodes. Most of these methodologies require expensive equipment, time-consuming procedures, and expert personnel to execute. Near-infrared spe...

Nucleic acid enzymes (NAzymes) are a class of nucleic acid molecules with catalytic activity, which can be modulated by the presence of different species such as metal ions, genetic biomarkers, small molecules or proteins, among others. NAzymes offer several important advantages for development of novel bioanalytical strategies, resulting from thei...

Research in nanoscience and nanotechnology has widely developed in the past decade to the extent that today nanotechnology has established an interdisciplinary trend between almost all branches of science and technology. Particularly, the actual availability of novel nanodevices, nanotools, nanosensors, and nanosorbents, with varied functionalizati...

Breast milk is an optimal food that covers all the nutritional needs of the newborn. It is a dynamic fluid whose composition varies with lactation period. The neonatal units of hospitals have human milk banks, a service that analyzes, stores, and distributes donated human milk. This milk is used to feed premature infants (born before 32 weeks of ge...

Aflatoxin M1 (AFM1) is one of the most widespread aflatoxins that can be present in the milk of lactating mammals. It can cause carcinogenicity, mutagenesis, teratogenesis, genotoxicity and immunosuppression. The WHO recommends reducing the AFM1 concentration in food products, so the European Commission has set a maximum allowable limit of 0.05 µg...

Quantum dots (QDs) are crystalline inorganic semiconductor nanoparticles a few nanometers in size that possess unique optical electronic properties vs those of larger materials. For example, QDs usually exhibit a strong and long-lived photoluminescence emission, a feature dependent on size, shape and composition. These special optoelectronic proper...

Rapid, reproducible and ultrasensitive assays can be nowadays achieved in clinical analysis with the help of optical sensors based on varied principles such as surface plasmon resonance, photoluminescence, vibrational spectroscopy and several others. In fact, optical sensors and biosensors have consolidated as a mature technology in healthcare cont...

The increasing exploitation of metallic nanoclusters (NC) in many different applications (e.g., in optoelectronic developments, energy storage, diagnosis applications in biomedicine or therapeutic agents, among others) necessitates sensitive techniques to characterize and quantify such nanomaterials in terms of physicochemical properties, surface s...

MicroRNAs (miRNAs) have recently emerged as a new class of biomarkers for disease diagnosis and play vital roles in physiological and pathological processes. Here, a novel fiber-optic prototype that allows synchronized optical transmittance measurements at different wavelengths has been designed and fabricated for selective and sensitive miRNAs det...

Mercury (Hg) is one of the most toxic environmental pollutants, and is biocondensed via the food chain. Selenium (Se) is an essential element that possesses an antagonistic property towards Hg in vivo. The antagonistic property is explained by the assumption that Hg and Se directly interact to form HgSe nanoparticles (HgSe NPs) in organs. It is pre...

Highly porous nanoscale metal–organic frameworks (nanoMOFs) attract growing interest as drug nanocarriers. However, engineering “stealth” nanoMOFs with poly(ethylene glycol) (PEG) coatings remains a main challenge. Here we address the goal of coating nanoMOFs with biodegradable shells using novel cyclodextrin (CD)-based oligomers with a bulky struc...

There is a growing interest in the development of sensitive, portable, and low-cost instrumentation for optical chemical (bio)sensing. Such instrumentation can allow real-time decision-making for industry, farmers, and researchers. The combination of optical fiber schemes, luminescence spectroscopy techniques, and new materials for sensor immobiliz...

The current trends in modern medicine towards early diagnosis, or even prognosis, of different diseases have brought about the need for the corresponding biomarker detection at ever lower levels in really complex matrices. To do so, it is necessary to use proper extremely sensitive detection techniques such as elemental mass spectrometry. However,...

Quantitative bioimaging of Quantum Dots (QDs) uptake in single cells by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a challenging task due to the high sensitivity and high spatial resolution required, and to the lack of matrix-matched reference materials. In this work, high spatially resolved quantitative bioimaging o...

Introduction: Differential diagnosis between ischemic and hemorrhagic strokes in the acute stage is one of the major challenges of neurovascular research. Several biomarkers have been studied, but attempts to date have focused on determining their blood levels. Recently, cerebral lymphatic drainage toward the nostrils has been discovered, giving u...

A major challenge in the development of bioanalytical methods is to achieve a rapid and robust quantification of disease biomarkers present at very low concentration levels in complex biological samples. An immunoassay platform is presented herein for ultrasensitive and fast detection of the prostate-specific antigen (PSA), a well-recognized cancer...

ICP-MS has been widely used in Life Sciences for the absolute quantification of biomolecules without specific standards assuming the same response for generic compounds including complex biomolecules. However, contradictory results have been published on this regard. We present the first critical statistical comparison of the ICP-MS response factor...

The synthesis of new multifunctional engineered nanoparticles (ENPs) constitutes nowadays a research topic of increasing importance in nano(bio)technology. Such ENPs can be synthesized out of a large variety of different materials, being inorganic nanoparticles highly competitive in biomedical applications due to their unique optoelectronic propert...

Bio-formation and biodistribution of mercury selenide (HgSe) nanoparticles (NPs), as the ultimate metabolic product in the Hg detoxification pathway, is an important environmental and toxicological issue not well understood nowadays. In this work, we revealed for the first time the cellular uptake and accumulation of HgSe NPs in one embryonic and o...

A portable instrumental system was designed for the routine environmental monitoring of toxic volatile organic compounds (VOCs) in atmospheric conditions based on changes in the photoluminescence emission of semiconductor nanoparticles (quantum dots) entrapped in a sol-gel matrix as the solid sensing material. The sol-gel sensing material displayed...

Quantum dots (QDs) are a special type of engineered nanomaterials with outstanding optoelectronic properties that make them as a very promising alternative to conventional luminescent dyes in biomedical applications, including biomolecule (BM) targeting, luminescence imaging and drug delivery. A key parameter to ensure successful biomedical applica...

Quantum dots (QDs) are a special type of engineered nanomaterials with outstanding optoelectronic properties that make them as a very promising alternative to conventional luminescent dyes in biomedical applications, including biomolecule (BM) targeting, luminescence imaging and drug delivery. A key parameter to ensure successful biomedical applica...

Gold nanoparticles of different sizes have been synthesized and surface-functionalized with selected RNA probes in order to develop a rapid, low-cost and sensitive method for detection of microRNA146a (miR146a). The strategy is based on the change of colour that can be observed visually after aggregation of the RNA modified-gold nanoparticles (AuNP...

In this work, novel silver sulphide quantum dots (Ag2S QD) are electrochemically quantified for the first time. The method is based on the electrochemical reduction of Ag+ to Ag0 at −0.3 V on screen-printed carbon electrodes (SPCEs), followed by anodic stripping voltammetric oxidation that gives a peak of currents at +0.06 V which represents the an...

Background Differentiation between hemorrhagic and ischemic stroke is currently made by brain imaging or analyzing blood and cerebrospinal fluid (CSF) samples. After describing a new drainage route from brain to nasal mucosa, nasal exudate samples can be considered a new and promising source of biomarkers. Saliva can also be evaluated. Methods We...

Nanosized metal-organic frameworks (nanoMOFs) MIL-100(Fe) are highly porous and biodegradable materials that have emerged as promising drug nanocarriers. A challenging issue concerns their surface functionalization in order to evade the immune system and to provide molecular recognition ability, so that they can be used for specific targeting. A co...

The asymmetric flow field-flow fractionation (AF4) coupled on-line with elemental (inductively coupled plasma-mass spectrometry, ICP-MS) and molecular (fluorescence and UV) detection has been investigated as a powerful tool for the characterization of bioinorganic nano-conjugates. In this study, we described methods for the characterization of biot...

Nanoparticles are increasingly being used as advantageous alternatives to commonly used contrast agents in bioimaging, not only due to their improved imaging capabilities but also their great potential in theranostics. Herein, carbon quantum dots (CQDs) codoped with nitrogen and lanthanides (i.e., Gd and Yb) are synthesized using a one‐pot microwav...

Guest Editors, Ramon M. Barnes and José M. Costa-Fernandez, introduce this themed issue dedicated to Alfredo Sanz-Medel.

A remaining challenge nowadays in nanotechnology is the fast and reliable determination of the ratios between engineered nanoparticles and the species attached to their surface after chemical functionalization. The approach proposed herein based on the on-line coupling of asymmetric flow field-flow fractionation (AF4) with inductively coupled plasm...

Near infrared (NIR) emitting Ag2S quantum dots have been synthesized, characterized and evaluated for chemical sensing applications. After their optical characterization, it was observed that the Ag2S quantum dots present both, excitation and emission in the NIR region, and an excellent quantum yield of 33.2%. These features are of great value for...

Inorganic nanoparticles are a fascinating class of materials which promise great potential in numerous fields, including optical (bio)sensing. Many different kinds of such nanoparticles have been widely used for fluorescent sensing and imaging due to the different merits of fluorescent nanoparticles compared to molecular fluorophores. Progress made...

The use of functionalized magnetic particles is increasing because they simplify the analytical process and yield promising results in a wide range of applications. Particularly, streptavidin-coated magnetic beads offer the possibility of rapid and very efficient grafting of biomolecules. Unfortunately, current methods to monitor and compute this g...

Determination of stoichiometries between engineered nanoparticles and species attached to their surface after chemical functionalization or interaction with biological media has been a hotspot during the last years, still unsatisfactory solved. Herein we propose a new approach only requiring for a simple mass spectrometric sulfur isotope ratio meas...

The analytical potential of a nanosecond laser ablation inductively coupled plasma mass spectrometer (ns-LA-ICP-SFMS) system, equipped with an ultra-fast wash-out ablation chamber, is critically investigated for fast and high spatially...

Carbon dots have demonstrated great potential as luminescent nanoparticles in bioapplications. Although such nanoparticles appear to exhibit low toxicity compared to other metal luminescent nanomaterials, today we know that the toxicity of carbon dots (C-dots) strongly depends on the protocol of fabrication. In this work, aqueous fluorescent C-dots...

Additional experimental data.

Research in nanoscience and nanotechnology has widely developed to the extent that today there are a large variety of nanotools and nanomaterials providing exciting applications in most areas of Science and Technology. Particularly, the availability of materials and methods produced at the nanometer scale, with varied functionalization possibilitie...

Protein and peptide detection with inductively coupled plasma mass spectrometry (ICP-MS) can provide their direct and reliable absolute quantification without the need for specific standards, which greatly complements molecular mass spectrometry features in proteomics. We discuss recent research to shed new light on this particular surge in the ana...

Herein, high-quality Mn-doped ZnS quantum dots (QDs) have been synthesized using a facile approach directly in aqueous media. The surface of the obtained QDs was further modified by cap-exchange of the native cysteine shell with dihydrolipoic acid (DHLA) ligands resulting in nanocrystals with high water-stability having an intense phosphorescent si...

Coupling of asymmetric flow field-flow fractionation (AF4) to an on-line elemental detection (inductively coupled plasma-mass spectrometry, ICP-MS) has been recently proposed as a powerful diagnostic tool for characterization of the bioconjugation of CdSe/ZnS core-shell Quantum Dots (QDs) to antibodies. Such approach has been used herein to demonst...

Colloidal Mn2+-doped ZnS quantum dots (QDs) were synthesized, surface modified and thoroughly characterized using a pool of complementary techniques. Cap exchange of the native L-cysteine coating of the QDs with dihydrolipoic acid (DHLA) ligands is proposed as a strategy to produce nanocrystals with a strong phosphorescent-type emission and improve...

Antimony is a metalloid that affects biological functions in humans due to a mechanism still not understood. There is no doubt that the toxicity and physicochemical properties of Sb are strongly related with its chemical state. In this paper, the interaction between Sb(III) and Sb(V) with bovine serum albumin (BSA) was investigated in vitro by fluo...

Figure A. BSA excitation emission matrix. [BSA] = 0.75mM. BSA excitation emission matrix in PBS at pH 7.4. [BSA] = 0.75mM. Figure B. Synchronous fluorescence spectra for BSA. [BSA] = 0.75 μM. Synchronous fluorescence spectra for BSA at room temperature on dilution 1:1 (black line), 1:5 (red line), 1:10 (blue line), 1:20 (purple line). [BSA] = 0.75...

Table A. ICP-MS parameters. Optimal ICP-MS parameters for S and Sb measurement. Table B. BSA separation. Conditions of BSA separation by AF4. Table C. AF4 conditions for the separation of BSA structures. AF4 optimization conditions for the separation of BSA structures by AF4-ICP-QQQ ([BSA] = 0.75μM). Results are gven as individual relative percenta...

A flow system was designed and developed for continuous monitoring of acetone content dissolved in water samples. The system is based on the interaction of the acetone with a phosphorescent quantum dot entrapped in a sol-gel material, acting as a selective sensing material. The nanosensor displays an excitation peak centered in 290 nm, thus requiri...

Absolute protein quantification methods based on molecular mass spectrometry usually require stable isotope-labeled analogous standards for each target protein or peptide under study, which in turn must be certified using natural standards. In this work, we report a direct and accurate methodology based on capLC-ICP-QQQ and on-line isotope dilution...

Metal nanoparticle processing technologies have been widely developed to the extent that today it is possible to easily fabricate high‐quality photoluminescent semiconductor nanocrystals, known as ‘quantum dots’ (QDs). Nowadays, the commercial availability of QDs, with varied surface functionalization possibilities, has rendered them very attractiv...

Advancements in nanoscience enabled the synthesis of a diverse array of engineered nanomaterials. The precise control of the composition and quality of such nanomaterials is required to ensure their eventual successful application. Also importantly, the potentially adverse environmental and/or human health effects resulting from exposure to nanopar...

One of the major challenges in developing novel assay methods for the detection of biomolecules is achieving high sensitivity, because of the ultralow concentrations typically in clinical samples. Here, a Mn-doped ZnS quantum dots-based immunoassay platform is presented for highly sensitive detection of cancer biomarkers. Ultrahigh sensitivity is a...

HgSe nanoparticles (NPs) have been recognised as the ultimate product of mercury detoxification in biological systems. However, the exact mechanism of their formation and distribution in animals is not understood and thus well-characterized biocompatible engineered NPs would be invaluable to investigate such metabolic products. In this work, HgSe N...

Optical analysis based on fluorescence labeling has been extensively used for the selective tagging of a wide range of biomedical important targets or for sensing purposes. Fluorescent nanoparticles (NPs) offer interesting properties as labels, as they can be also used as active labels that change their properties upon changes in the environment, s...

Hyphenation of asymmetric flow field-flow fractionation (AF4) to an on-line elemental detection (inductively coupled plasma-mass spectrometry, ICP-MS) is proposed as a powerful diagnostic tool for quantum dots bioconjugation studies. In particular, conjugation effectiveness between a “model” monoclonal IgG antibody (Ab) and CdSe/ZnS core-shell Quan...

A one-step synthesis of near infrared fluorescent platinum nanoclusters (PtNCs) in aqueous medium is described. The proposed optimized procedure for PtNC synthesis is rather simple, fast and it is based on the direct metal reduction with NaBH4. Bidentated thiol ligands (lipoic acid) were selected as nanoclusters stabilizers in water media. The stru...

A generic strategy based on the use of CdSe/ZnS Quantum Dots (QDs) as elemental labels for protein quantification, using immunoassays with elemental mass spectrometry (ICP-MS), detection is presented. In this strategy, streptavidin modified QDs (QDs-SA) are bioconjugated to a biotinylated secondary antibody (b-Ab2). After a multi-technique characte...

The field of nanoscience and nanotechnology is continuously growing, providing the Society with novel nanomaterials enabling applications in different strategic sectors (industry, environment, energy, medicine, food, etc.) that improve humans’ quality of life. In this context, the precise control of the quality and physicochemical properties offere...

Separation and identification of nanoparticles of different composition, with similar particle diameter, coexisting in heterogeneous suspensions of polymer-coated CdSe/ZnS quantum dots (QDs) have been thoroughly assessed by asymmetric flow field-flow fractionation (AF4) coupled on-line to fluorescence and inductively coupled plasma mass spectrometr...

This article gives an overview of the different techniques used to identify, characterize, and quantify engineered nanoparticles (ENPs). The state-of-the-art of the field is summarized, and the different characterization techniques have been grouped according to the information they can provide. In addition, some selected applications are highlight...

Metal nanoclusters (NCs), composed of several to tens of atoms, are a new class of fluorescent nanoprobes. NCs present distinct and favourable optical, electrical, and chemical properties as compared to other large-scale nanomaterials or bulk materials with the same chemical composition, being attractive for bio-imaging and bio-labelling applicatio...

The performance of radiofrequency (rf) millisecond pulsed glow discharge (PGD) coupled to a fast orthogonal time-of-flight mass spectrometer (TOFMS) for chemical characterization and quantification of organic volatile compounds was investigated by using two different GD chamber designs. The designs investigated had substantial differences in the wa...

Optical atomic spectrometry addresses the determination of the elemental composition of a given sample (it can be gas, liquid, or solid) by measuring the corresponding absorbed or emitted electromagnetic radiation (typically, the spectrum of intensity vs. wavelength is collected) after interaction with such radiation coming from a proper energetic...

Determination of bromate ions in contaminated flour samples by using a room temperature phosphorescence (RTP) optosensor is described. The optosensor is based on the non-radiative energy transfer from α-bromonaphthalene (a phosphorescent molecule insensitive to the presence of the analyte) acting as donor, to an energy acceptor bromate-sensitive mo...

A one-step aqueous synthesis of highly fluorescent water-soluble copper nanoclusters (CuNCs) is here described, based on direct reduction of the metal precursor with NaBH4 in the presence of bidentate ligands (made of lipoic acid anchoring groups, appended with a poly(ethylene glycol) short chain). A complete optical and structural characterization...

The intentional introduction of transition metal impurities into semiconductor nanocrystals is an attractive approach for tuning quantum dot photoluminescence emission. Particularly, doping of ZnS quantum dots with Mn(2+) (Mn:ZnS QDs) results in a phosphorescence-type emission, attributed to the incorporation of manganese ions into the nanocrystal...

The principles, instrumentation, and analytical performance of most common quantitative atomic techniques based on optical spectrometry (absorption, emission or fluorescence) and mass spectrometry for the analysis of liquid samples and for direct solid analysis are outlined. Emphasis is given to conceptual explanations aiming to stress the advantag...