Diego Pessoa Rocha

• PhD
• Professor at Paraná Federal Institute of Education, Science and Technology

Developing new sensors presenting low-cost, portability, and disposability features is of paramount in the electrochemical field. Thus, this work proposes the fabrication of lab-made composite electrodes using acrylonitrile butadiene styrene, graphite, and aluminum oxide. In this investigation, the amount of aluminum oxide (0 to 12.25 w/w) was care...

Monitoring nitrate in aquatic systems is of fundamental importance since its presence at high levels can result in adverse effects on human health. Thus, in this work, manufactured carbon black (CB)/polylactic acid (PLA)-based 3D-printed electrochemical sensors modified with electrodeposited silver particles (AgPs) for nitrate analysis in real wate...

Resorcinol (RS) is a phenolic compound widely used in industrial segments, being used mainly as a disinfectant and antiseptic for skin care. However, this compound can be extremely toxic for both the environment and humans. Thus, the search for new analytical strategies to monitor this compound is of paramount importance. Therefore, the present wor...

The combination of CO2 laser ablation and electrochemical surface treatments is demonstrated to improve the electrochemical performance of carbon black/polylactic acid (CB/PLA) 3D-printed electrodes through the growth of flower-like Na2O nanostructures on their surface. Scanning electron microscopy images revealed that the combination of treatments...

The 3D printing (or additive manufacturing, AM) technology is capable to provide a quick and easy production of objects with freedom of design, reducing waste generation. Among the AM techniques, fused deposition modeling (FDM) has been highlighted due to its affordability, scalability, and possibility of processing an extensive range of materials...

This paper presents a new modified electrode that combines the high electrical conductivity of carbon nanotubes (CNTs) with the catalytic sites of WS2 (named WS2/CNTs) for isoniazid detection. Electrochemical and electroanalytical properties of the WS2/CNTs/GCE-modified electrodes were investigated by cyclic voltammetry (CV) and differential pulse...

Multifunctional nanomaterials have been attracting increasing attention as solutions to the existing challenges in energy systems and sensing technologies. In this regard, multifunctional NiVCe-layered double hydroxide (NiVCe-LDH) nanoparticles were synthesized by the modified sol-gel method. The analysis of this material demonstrated excellent pot...

For the first time the development of an electrochemical method for simultaneous quantification of Zn²⁺ and uric acid (UA) in sweat is described using an electrochemically treated 3D-printed working electrode. Sweat analysis can provide important information about metabolites that are valuable indicators of biological processes. Improved performanc...

The use of additive manufacturing or three-dimensional (3D) printing has revolutionized different fields of science. Among the well-known advantages of this new technology, its low cost, reproducibility, large-scale production, and freedom to manufacture custom-made devices can be highlighted. In electrochemistry, 3D printing has been widely used i...

This mini-review presents an overview of recent trends for 3D printed sensors and biosensors (with a focus on Fused Deposition Modeling (FDM) based technology), along with their posttreatment surfaces to improve electrochemical applications. The protocols described in the literature and advances in this field were covered, bringing a critical discu...

Conductive 3D-printed platforms have been recognized an emerging class of materials with great potential to electrochemistry. However, such 3D-printed electrodes require a surface treatment to remove excess of polymer that hinders the electron transfer. We report a fast (2-min) and chemical-free protocol for the surface treatment of 3D-printed cond...

Metal organic frameworks (MOFs) are hybrid materials built with both organic and inorganic components. The potential of these structures was highlighted in the 1990s and since then over 90,000 articles dealing with MOFs have been published (still growing rapidly), demonstrating a wide variety of applications. However, the improvement in the electro...

3D printing is the most popular form of additive manufacturing, and conductive 3D-printed platforms have been recognized as an emerging class of devices with high potential for electrochemistry. Nevertheless, as-printed electrodes provide poor conductivity due to the presence of high amounts of insulating thermoplastic material, requiring surface p...

Spinel MCo2O4 (M = Ni, Fe, Mn, Cu and Zn) demonstrates excellent physicochemical properties due to combined effects of M2+ and Co2+ cations. Their inimitable optical, electronic, and mechanical properties open up windows for a broad range of promising applications. The development of novel spinels has opened virtually infinite possibilities for the...

Viruses are the causing agents for many relevant diseases, including influenza, Ebola, HIV/AIDS, and COVID-19. Its rapid replication and high transmissibility can lead to serious consequences not only to the individual but also to collective health, causing deep economic impacts. In this scenario, diagnosis tools are of significant importance, allo...

Viruses are the causing agents for many relevant diseases, including influenza, Ebola, HIV/AIDS, and COVID-19. Its rapid replication and high transmissibility can lead to serious consequences not only to the individual but also to collective health, causing deep economic impacts. In this scenario, diagnosis tools are of significant importance, allo...

In this review, electrocatalysts for HER/OER/ORR and energy storage electrode materials based on MnCo2O4 were reviewed considering their key multifunctional role in the way to a more sustainable society.

The monitoring of species of medical, environmental, and industrial interests has been urgently demanded. Several times, the necessity of point of care and/or point of use is important to obtain precise and rapid quantification, in which wearable and flexible disposable electrochemical sensors and biosensors have been great alternatives. In this co...

The application of graphene and its derivatives, graphene oxide and reduced graphene oxide, has proportioned an increase in the analytical parameters of sensors, especially regarding the sensibility, selectivity, and catalytic parameters. The performance of the sensor is directly influenced by the synthesis method, which will define the purity, num...

The energy requirement of the modern society increases every day. The depletion of the reserves of fossil fuel associated with the deleterious effects of CO2 in the atmosphere are forcing all the world to search for alternative ways of generation and storing energy. Many scientists around the world are pursuing different ways to produce and store e...

This work presents a novel procedure involving the sequential chemical treatment to generate reduced graphene oxide (rGO) within 3D-printed polylactic acid (PLA) electrodes and their potential applications for sensing and biosensing. A new configuration of a compact all-3D-printed electrochemical device containing the three electrodes is presented,...

We report a 3D-pen fabricated electrochemical sensor using biodegradable carbon black/polylactic acid (PLA) filament for on-site monitoring of lead and copper in aqueous and hydroethanolic media. The sensors consist of 3D-printed PLA concentric tubes filled with conductive carbon-black/PLA in a similar design to a disc working electrode. Under opti...

In this study we propose an in situ low-cost electrochemical treatment by cyclic voltammetry (CV) for graphene oxide (GO) synthesis on the surface of graphite/ABS composite electrodes. Higher efficiencies were achieved while CV treatments were carried out in alkaline (KOH) background electrolyte, applying an elevated number of successive cycles (10...

The fabrication of carbon black/polylactic acid (PLA) electrodes using a 3D printing pen is presented and compared with electrodes obtained by a desktop fused deposition modelling (FDM) 3D printer. The 3D pen was used for the fast production of electrodes in two designs using customized 3D printed parts to act as template and guide the reproducible...

3,4-Methylenedioxymethamphetamine (MDMA) is an illicit stimulant drug also known as ‘ecstasy’ and is one of the most used amphetamines worldwide. Similar drugs to MDMA, so called as novel psychoactive substances (NPS), have been also found in seized samples. In this work, we present a simple and fast electrochemical method for MDMA detection in sei...

We review the contributions of 3D-printing to fabricate electrochemical sensors.

We present an electroanalytical method using square-wave anodic stripping voltammetry on electrochemically-treated screen-printed gold electrodes to the simultaneous determination of lead(II), copper(II) and mercury(II) in struvite (natural fertilizer produced from urine). Electrochemical treatment via cyclic voltammetry of the working electrodes i...

Herein, we report the improved detection of Zn²⁺ via square-wave anodic stripping voltammetry utilizing an electrochemically treated screen-printed gold electrode. Surface analysis of the gold surface revealed increase in rugosity, removal of residual polymeric ink, and consequent higher access to gold microparticles after electrochemical treatment...

A high oxalate uptake from the diet is thought to play a role in the development of hyperoxaluria, a documented risk factor in the formation of calcium oxalate kidney stones. In this sense, a flow system designed with multicommutation is proposed for spectrophotometric determination of oxalate in tea. The procedure is based on the SPADNS method (a...

Additive manufacturing is a promising technology for the rapid and economical fabrication of portable electroanalytical devices. In this paper we seek to determine how our bespoke additive manufacturing feedstocks act as the basis of an electrochemical sensing platform towards the sensing of manganese(II) via differential pulse cathodic stripping v...

This work shows that the electrochemical activity of a 3D-printed electrode fabricated using a conductive composite of polylactic acid (PLA) containing carbon black (CB) can be substantially improved through a simple and fast chemical/electrochemical pretreatment in 0.5 mol L⁻¹ NaOH. Scanning electron microscopy and infrared spectroscopy data showe...

Additive manufacturing or three-dimensional (3D)-printing is an emerging technology that has been applied in the development of novel materials and devices for a wide range of applications, including Electrochemistry and Analytical Chemistry areas. This review article focuses on the contributions of 3D-printing technology to the development of elec...

In this thesis the development of efficient electrochemical sensors based on carbon nanostructured materials (graphene and nanotubes) was demonstrated. For this, three synthesis methods were used (electrochemical, drop casting and interfacial). The performance of these sensors was investigated using, as model analytes, hydroquinone (HQ), catechol (...

This work presents a simple electrochemical method for 2-naphthylamine (2NAP) determination in perfume by differential-pulse voltammetry (DPV) employing a boron-doped diamond (BDD) electrode cathodically treated. Simple dilution of sample in supporting electrolyte was performed before electrochemical analysis. A borate buffer solution of pH 10.0 co...

Additive manufacturing, also known as 3D-printing, is receiving great interest by chemists due to the easy design of novel materials, fast prototyping and reducing waste, which enables large-scale fabrication of electrochemical devices. Herein we demonstrate the development of (bio)sensors for the analysis of biological fluids using 3D-printing. Fu...

Herein, we report a complete additively manufactured (AM) electrochemical sensing platform. In this approach, a fully AM / 3D-printed electrochemical system, using a conventional low-cost 3D-printer (fused deposition modelling) fabricating both the conductive electrodes and non-conductive/chemically inert electrochemical cell is reported. The elect...

A highly-sensitive method for Cu(II) determination employing single-drop microextraction (SDME) sample prior graphite-furnace atomic absorption spectrometry (GF AAS) is described. The chelating agent 1-(2-thiazolylazo)-2-naphthol was used for copper complexation and favor mass transfer to the extractor solvent drop. An accessory for mechanized inje...

A novel and indirect voltammetric procedure for the selective determination of formaldehyde is described. It is based on the oxidation of 3,5–diacetyl–1,4–dihydrolutidine (DDL) on an unmodified glassy-carbon electrode (GCE), generated by the selective reaction between formaldehyde and acetylacetone. A single oxidation peak of DDL at +0.8 V was obse...

We present a low‐cost mechanized system fabricated using fused deposition modelling 3D‐printing technology to manipulate microvolumes and perform injections on an electrochemical cell in wall‐jet configuration. As a proof‐of‐concept, the amperometric detection of paracetamol (model analyte) on a screen‐printed electrode using 0.5 μL aliquots result...

This work presents the development and characterization of a new chemically modified electrode exploiting recordable Au-rewritable compact discs (AuCDs) as substrate for drop casting of a chemically-reduced graphene-oxide slurry focusing on simple and low-cost electrochemical sensors. Increase in electrochemical responses in cyclic voltammetric and...

Forensic chemistry is the application of analytical chemistry to forensic analysis and is today one of the hot topics in the scientific literature as it can provide valuable information regarding crimes that have been committed and assist in their resolution. The literature in the field of forensic chemistry has been exponentially growing and cover...

Forensic chemistry is the application of analytical chemistry to forensic analysis and is today one of the hot topics in the scientific literature as it can provide valuable information regarding crimes that have been committed and assist in their resolution. The literature in the field of forensic chemistry has been exponentially growing and cover...

This paper presents a new route to produce carbon nanotube/reduced graphene oxide (CNT/rGO) nanocomposites using the interfacial method to produce high-performance electroanalytical sensing. The nanocomposite thin-film is formed at the cyclohexane/water immiscible interface after stirring of a mixture of CNT and rGO in the biphasic solution and can...

Since the development of batch-injection analysis (BIA) in 1990, the technique has been constantly upgraded, especially for electrochemical systems, including the creation of novel cell designs and association with new accessories to cover a wide range of applications. BIA systems have provided faster, portable, and more precise analyses. In additi...

The electrochemistry of hydroquinone (HQ), catechol (CT), and dopamine (DP) on a glassy-carbon electrode (GCE) modified with chemically (CRGO) and electrochemically reduced graphene oxide (ERGO) was investigated and compared for the development of amperometric and voltammetric sensors. Cyclic voltammetric measurements showed higher current on the C...

This work presents the use of solenoid micro-pumps as a new strategy for sample introduction in batch-injection analysis (BIA). The volume of solution dispensed on each pulse of the solenoid micro-pump (μL) is used as fixed and reproducible injection volume for BIA. In this system, the injection steps are possible in stopped flow mode resulting in...

This work presents a simple electrochemical method for Hg determination in fish oil capsules using anodic stripping voltammetry (ASV) on a screen-printed gold electrode (SPGE). Samples were treated in an ultrasonic bath for 15 min in the presence of a 1 : 1 (v/v) concentrated HCl/H2O2 mixture at room temperature. The limit of detection (LOD) was es...

This communication shows the improved performance of electrochemically-reduced graphene oxide (ERGO) modified electrodes for the square-wave voltammetric detection of cocaine (COC) and its main adulterants paracetamol (PAR), caffeine (CAF) and levamisole (LEV). The four compounds can be identified in a single voltammetric scan on the ERGO-modified...

This work showed a flow system designed with solenoid valves for preconcentration of fluoride using SPADNS method in water samples. The analyte was preconcentrated in a mini-column coated with Layered Double Hydroxides (LDH) used as adsorbent. Then, the fluoride ions were eluted with 0.5 mol L⁻¹ sodium hydroxide and determined by spectrophotometry....

This work presents a portable electrochemical system for the continuous monitoring of corrosion inhibitors in a wide range of matrices including ethanol, seawater and mineral oil following simple dilution of the samples. Proof-of-concept is demonstrated for the sensing of 2,5-dimercapto-1,3,5-thiadiazole (DMCT), an important corrosion inhibitor. Di...

This work demonstrates that the electrochemistry of different molecules of pharmaceutical interest, including omeprazole, ciprofloxacin, dopamine, catechol, hydroquinone, and the antioxidants tert-butylhydroquine, gallic acid, propyl gallate, and pyrogallol, is affected by the functionalization of multi-walled carbon nanotubes (MWCNTs). Voltammetri...

Antibiotic resistance has been growing at an alarming rate and consequently the arsenal of effective antibiotics against Gram-negative and Gram-positive bacteria has dropped dramatically. In this sense there is a strong need to produce new substances that not only have good spectrum of activity, but having new mechanisms of action. In this regard,...

Antibiotic resistance has been growing at an alarming rate and consequently the arsenal of effective antibiotics against Gram-negative and Gram-positive bacteria has dropped dramatically. In this sense there is a strong need to produce new substances that not only have good spectrum of activity, but having new mechanisms of action. In this regard,...