Low-cost Biosensor Research Articles

Laser induced self-N-doped porous graphene as an electrochemical biosensor for femtomolar miRNA detection

We report a sensitive, yet low-cost biosensor based on laser induced graphene for femtomolar microRNA (miRNA) detection. Combined with the miRNA extraction and magnetic isolation process, the target miRNAs were purified for further detection using laser induced graphene sensor. The laser induced graphene was prepared by direct laser writing on commercial polyimide (PI) and patterned via a computer-aided design system as an electrode for electrochemical biosensing. We found that the laser reduction of PI resulted in nitrogen-doped porous graphene, not only improving its conductivity but also its sensitivity to nucleic acids. Preeclampsia specific miRNA hsa-miR-486-5p was magnetically purified and directly adsorbed on the surface of graphene electrode via graphene-miRNA affinity interaction. Surface attached miRNAs were then electrochemically quantified using [Fe(CN)6]3-/4- redox system. Our assay demonstrates detection of miRNA has-miR-486-5p up to concentrations as low as 10 fM with excellent reproducibility. Owing to its facile fabrication, low cost and high performance, the laser induced N-doped graphene biosensor presented here shows great potential for applications in detecting miRNA in biomedical applications.

Image Analytics for Food Safety

Infectious diseases and environmental pollution caused by toxic chemical agents such as heavy metals are significant concerns in the global world. For example, Mercury (Hg) and Arsenic (As) have been recognized as chemical threats for human health. It is difficult to achieve multiple detections of different types of targets in lateral flow strips because of the multiple reagent requirements, while microfluidic paper-based analytical devices (μ-PADS) can provide independent channels and testing areas for colorimetric analysis. Herein, our group develops a low-cost, multiplexing, instrument-free, and simple paper-based fluidics biosensor to quantitatively determine Hg and As amounts in a linear range of 0 ppm - 30 ppm with a detection limit of 1 ppm and 2 ppm, respectively. We will present an overview of the results obtained with our fabrication process, the design of the preliminary pattern and image analysis of the responses in the test area, and the specificity test and stability test results.

Coupling of short DNAs with reduced graphene oxide for electronic and sensing applications

In this article, we described an approach for coupling of short DNAs with reduced graphene oxide and thus formation of transducer layer for biological sensors. We investigated the dependence of coupling ratio on the graphene oxide reduction level. We found optimal reduction parameters and showed successful conjugation of aptamers with reduced graphene oxide. We have revealed a trend to increase aptamer conjugation efficiency with a decrease of graphene oxide reduction rate. Finally, we made biosensor structures with Π-shaped reduction pattern and showed excellent sensitivity of the sensor during thrombin exposure. These results are important for the development of flexible low-cost biosensors of a new generation.

Overview of Different Milk and Milk Products Contaminant Detections by Biosensors

Food diseases and allergies are one of the important causes having major impact on health of the world population. Being one of the basic needs of nutrition, milk and milk products are important types of packed foods which are consumed by the modern world population. Milk sources get contaminated due to different sources like pesticide residues, heavy metals, and aflatoxin during the process of cattle feeding, pre-processing, and improper handling during post processing period. Therefore, there is a need of the society to have a more accurate, fast in response, durable and stable analytical device to detect different milk contaminants in packed milk and milk products. Current development in biosensors provides new hope to achieve the goal of milk contaminants detection more precisely and accurately. Hence the basic inclination behind this paper is to study the recent developments in different types of biosensors used in dairy industry and find out future prospective in biosensor development for milk contaminants. In this survey paper we have studied 26 research articles on Biosensor detection techniques used to detect milk contaminants like Urea, Antibiotics, and Metal ions with their different design parameters and implementation strategy. The detection limit analysis of different methods is recorded in the view of deciding the future research path in each of the methods. In future, combination of nanotechnology with electrochemical biosensors and optical biosensors with some modifications can provide highly sensitive, rapid, potable and low-cost biosensors for detection of milk contaminant.

Reduced graphene oxide based nanobiocomposite as basis for flexible biosensors

Flexible selective electrochemical biosensor based on reduced graphene oxide film and short oligonucleotides (aptamers) was developed. Laser scribing was applied for graphene reduction due to controllable reduction rate and simple devises pattering. Optimal parameters of film reduction were determined for effective aptamers coupling, by varying laser output power. Mild reduced graphene oxide, as was expected, revealed better reactivity for aptamers coupling. Resistive response to biosensors exposure to thrombin and albumin proteins was measured. As a result we developed bionanocomposite that can be used in a new generation of available low-cost biosensors.

D-shaped plastic optical fibre aptasensor for fast thrombin detection in nanomolar range

The development of optical biosensors for the rapid and costless determination of clinical biomarkers is of paramount importance in medicine. Here we report a fast and low-cost biosensor based on a plasmonic D-shaped plastic optical fibre (POF) sensor derivatized with an aptamer specific for the recognition of thrombin, the target marker of blood homeostasis and coagulation cascade. In particular, we designed a functional interface based on a Self Assembled Monolayer (SAM) composed of short Poly Ethylene Glycol (PEG) chains and biotin-modified PEG thiol in ratio 8:2 mol:mol, these latter serving as baits for the binding of the aptamer through streptavidin-chemistry. The SAM was studied by X-ray Photoelectron Spectroscopy (XPS) analysis, static contact angle (CA), Surface Plasmon Resonance (SPR) in POFs, and fluorescence microscopy on gold surface. The optimized SAM composition enabled the immobilization of about 112 ng/cm2 of aptamer. The thrombin detection exploiting POF-Aptasensor occurred in short times (5–10 minutes), the reached Limit of Detection (LOD) was about 1 nM, and the detection range was 1.6–60 nM, indicating the POF-Aptasensor well addresses the needs for a low-cost, simple to use and to realize, rapid, small size and portable diagnostic platform.

Carbon Nanomaterial-Based Biosensors: A Review of Design and Applications

Biosensors have become a key research domain owing to their potential applications in numerous areas, such as food and water safety, human health management, and environmental monitoring. Various carbon-based nanomaterials have been extensively studied in biosensor-related works and are considered the most promising candidates for producing sensitive, rapid, and low-cost biosensors. In this article, carbon nanotubes (CNTs), graphene, and graphene oxide (GO) are discussed for the development of various biosensors. We examine multiple areas in the design of biosensors, highlighting their possible applications and assorted fabrication techniques.

Portable and low-cost biosensor towards on-site detection of diclofenac in wastewater

Wastewater treatment plants are the main release sources of pharmaceutical compounds present in surface waters. Even at low concentrations, many of these substances have long-term adverse effects on the environment. For an efficient control of pharmaceutical removal, a real-time recognition is a prerequisite. Currently, quantification of such compounds is done in special equipped laboratories and is rather time-consuming and expensive. Here, we introduce a novel biosensor for the detection of the pharmaceutical compound diclofenac, which can be produced with low costs, is easy in handling and can be applied directly on-site. Recognition of diclofenac is based on genetically engineered yeast cells which produce green fluorescent protein in a diclofenac concentration-dependent manner. Centerpiece of the sensor is a foil-based microfluidic flow cell, which allows supply with nutrient solution and analyte while preventing loss of reporter cells. Readout of data is accomplished by a newly developed spectrometric detection unit. With this device, we are able to determine diclofenac concentrations in a range from 10 to 50 μM.

Low-cost and user-friendly biosensor to test the integrity of mRNA molecules suitable for field applications

The use of mRNA in biotechnology has expanded with novel applications such as vaccines and therapeutic mRNA delivery recently demonstrated. For mRNA to be used in patients, quality control assays will need to be routinely established. Currently, there is a gap between the highly sophisticated RNA integrity tests available and broader application of mRNA-based products by non-specialist users, e.g. in mass vaccination campaigns. Therefore, the aim of this work was to develop a low-cost biosensor able to test the integrity of a mRNA molecule with low technological requirements and easy end-user application. The biosensor is based on a bi-functional fusion protein, composed by the λN peptide that recognizes its cognate aptamer encoded on the 5’ end of the RNA under study and β-lactamase, which is able to produce a colorimetric response through a simple test. We propose two different mechanisms for signal processing adapted to two levels of technological sophistication, one based on spectrophotometric measurements and other on visual inspection. We show that the proposed λN-βLac chimeric protein specifically targets its cognate RNA aptamer, boxB, using both gel shift and biolayer interferometry assays. More importantly, the results presented confirm the biosensor performs reliably, with a wide dynamic range and a proportional response at different percentages of full-length RNA, even when gene-sized mRNAs were used. Thus, the features of the proposed biosensor would allow to end-users of products such as mRNA vaccines to test the integrity of the product before its application in a low-cost fashion, enabling a more reliable application of these products.

Simultaneous detection of glucose, uric acid and cholesterol using flexible microneedle electrode array-based biosensor and multi-channel portable electrochemical analyzer

The development of versatile and low-cost biosensor system for rapid and simultaneous detection of multiple blood metabolites is highly demanded for home healthcare. We developed a flexible microneedle electrode array-based biosensor (MEAB) and a multi-channel portable electrochemical analyzer (MPEA) for the simultaneous detection of glucose, uric acid, and cholesterol. Microneedle electrode array (MEA) was fabricated on the flexible substrate using magnetorheological drawing lithography, followed by sputter coated with Au/Ti film. Then, through biofunctionalized with glucose oxidase, uricase and cholesterol oxidase, MEA was conditioned as a biosensor for simultaneous detection of glucose, uric acid and cholesterol. MEAB demonstrated excellent sensing performance with a wide linear range (glucose, 2–12 mM; uric acid, 0.1–1.2 mM; cholesterol, 1–12 mM), low detection limit (glucose, 260 μM; uric acid, 4 μM; cholesterol, 440 μM), and rapid response time (∼4 s). MPEA, a homemade ARM STM32 microcontroller-based electrochemical analyzer, was validated to be comparable to that of the commercial electrochemical workstation. MPEA integrated with flexible MEAB could accurately and simultaneously detect glucose, uric acid, and cholesterol levels in serum, and the results were consistent with the portable electrochemical device. The ease-of-use of the reported biosensor system will facilitate effective monitoring of blood metabolites at home.

Integrated Collinear Refractive Index Sensor with Ge PIN Photodiodes

Refractive index sensing is a highly sensitive and label-free detection method for molecular binding events. Commercial implementations of biosensing concepts based on plasmon resonances typically require significant external instrumentation such as microscopes and spectrometers. Few concepts exist that are based on direct integration of plasmonic nanostructures with optoelectronic devices for on-chip integration. Here, we present a CMOS-compatible refractive index sensor consisting of a Ge heterostructure PIN diode in combination with a plasmonic nanohole array structured directly into the diode Al contact metallization. In our devices, the photocurrent can be used to detect surface refractive index changes under simple top illumination and without the aid of signal amplification circuitry. Our devices exhibit large sensitivities > 1000 nm per refractive index unit in bulk refractive index sensing and could serve as prototypes to leverage the cost-effectiveness of the CMOS platform for ultra-compact, low-cost biosensors.

(Invited) Solution-Gated Organic Thin Film Transistors for High-Performance Biosensors

Solution-gated organic thin film transistors (SGOTFT) have shown promising applications in biosensors due to the high sensitivity, low working voltage and the simple design of the devices. SGOTFTs normally have no gate dielectric and the gate voltages are applied directly on the solid/electrolyte interfaces or electric double layers near the channel and the gate, which leads to the working voltages of the devices to be less than 1 V. On the other hand, SGOTFTs can be easily prepared by solution process or other convenient methods because of the much simpler device structure compared with that of a conventional field effect transistor with several layers. Recently, we have developed many types of biosensors based on SGOTFTs. The sensing mechanisms are attributed to the potential changes across solid/electrolyte interfaces induced by electrochemical reactions of analytes or the interactions between the analytes and the devices. Most of the devices have shown ultrahigh sensitivity due to the inherent amplification function of the transistors. I will introduce several types of SGOTFT-based biosensors for the detection of DNA/RNA, glucose, dopamine, uric acid, cells and proteins, which have been studied by our group recently. One major problem of the previously report SGOTFT-based biosensors is the poor selectivity, which should be solved in practical applications. We found that SGOTFT-based biosensors can show both high sensitivity and selectivity when the devices are modified with functional nano-materials (e.g. graphene, Pt nanoparticles) and biomaterials (e.g. enzyme, antibody, DNA) on the gate electrodes or the channel. The devices were successfully used for the selective detections of uric acid level and glucose level in saliva, which renders the devices promising transducers for noninvasive detections of biomarkers in human body. Since the organic devices are flexible and solution processable, we have developed the devices for wearable applications. SGOTFTs were prepared on plastic or fabric substrates by solution process and showed excellent stability in device performance during bending tests. SGOTFTs prepared on thin fibers were woven together with cotton yarns successfully by using a conventional weaving machine, resulting in flexible and stretchable fabric biosensors with high performance. The fabric sensors showed much more stable signals in the analysis of moving aqueous solutions than planar devices due to a capillary effect in fabrics. The devices were integrated in diapers for real-time analysis of urine and demonstrated glucose levels in urine with high sensitivity. Due to their low working voltages, the fabric devices were remotely operated by using a mobile phone, offering a unique platform for convenient wearable healthcare monitoring. The analysis of protein biomarkers is of great importance in the diagnosis of diseases. Although many convenient and low-cost electrochemical approaches have been extensively investigated, they are not sensitive enough in the detection of protein biomarkers with low concentrations in physiological environments. We prepared a novel SGOTFT-based biosensor that can successfully detect cancer protein biomarkers with ultrahigh sensitivity. The devices are operated by detecting electrochemical activity on gate electrodes, which is dependent on the concentrations of proteins labelled with catalytic nanoprobes. The protein sensors can specifically detect a cancer biomarker, human epidermal growth factor receptor 2, down to the concentration of 10-14 g/mL, which is several orders of magnitude lower than the detection limits of previously reported electrochemical approaches. Moreover, the devices can successfully differentiate breast cancer cells from normal cells at various concentrations. This work paves a way for developing highly sensitive and low-cost biosensors for the detection of various protein biomarkers in clinical analysis in the future. Reference [1] Lin P., Yan F., et al. Adv. Mater. 23, (2011) 4035-4040. [2] Tang H., Yan, F. et al. Adv. Funct. Mater. 21, (2011) 2264-2272. [3] Liao C. Z., Yan F., et al. Adv. Mater. 27, (2015) 676-681. [4] Lin P., Yan F., et al. Adv. Mater, 22, (2010) 3655-3660. [5] Fu Y., Yan F., et al. Adv. Mater. (2017) 29, 1703787. [6] Liao C. Z., Yan F., et al. Adv. Mater. 27, (2015) 7493-7527. [7] Liu S. H., Yan F. et al Adv. Mater. 29, (2017) 1701733. [8] Yang A. N., Yan F. et al. Adv. Mater. 29, (2018) in press.

Direct Laser Writing of Nanophotonic Structures on Contact Lenses.

Contact lenses are ubiquitous biomedical devices used for vision correction and cosmetic purposes. Their application as quantitative analytical devices is highly promising for point-of-care diagnostics. However, it is a challenge to integrate nanoscale features into commercial contact lenses for application in low-cost biosensors. A neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (1064 nm, 3 ns pulse, 240 mJ) in holographic interference patterning mode was utilized to produce optical nanostructures over the surface of a hydrogel contact lens. One-dimensional (925 nm) and two-dimensional (925 nm × 925 nm) nanostructures were produced on contact lenses and analyzed by spectroscopy and angle-resolve measurements. The holographic properties of these nanostructures were tested in ambient moisture, fully hydrated, and artificial tear conditions. The measurements showed a rapid tuning of optical diffraction from these nanostructures from 41 to 48°. The nanostructures were patterned near the edges of the contact lens to avoid any interference and obstruction to the human vision. The formation of 2D nanostructures on lenses increased the diffraction efficiency by more than 10%. The versatility of the holographic laser ablation method was demonstrated by producing four different 2D nanopattern geometries on contact lenses. Hydrophobicity of the contact lens was characterized by contact angle measurements, which increased from 59.0° at pristine condition to 62.5° at post-nanofabrication. The holographic nanostructures on the contact lens were used to sense the concentration of Na+ ions. Artificial tear solution was used to simulate the conditions in dry eye syndrome, and nanostructures on the contact lenses were used to detect the electrolyte concentration changes (±47 mmol L–1). Nanopatterns on a contact lens may be used to sense other ocular diseases in early stages at point-of-care settings.

Automated triage parameters estimation from ECG.

Low-cost biosensors combined with low-cost portable devices can be very useful in time critical situations of mass casualties, when fast triage procedure must be attained. A methodology that uses ECG to derive the vital parameters (heart rate and respiratory rate) needed for the triage procedure is presented and it is aimed to leverage affordable low-cost equipment that can be easily utilized by urgent medical units or even volunteers in events of considerable number of injured civilians. The methodology relies on selected well-known and published algorithms for heart rate and respiratory rate derivation from a given ECG signal. It consists of methods for R-wave detection, kurtosis computation, smoothing, and finding peaks. The proposed approach is shown to offer a good trade-off between the accurate measurement of the parameters and their fast derivation. It has been evaluated by using a publicly available database. Its robustness is measured in terms of accuracy estimation, showing a sensitivity of 0.87 for heart rate and 0.74 for respiratory rate, a sensitivity of 0.76 considering the triage process and an average-case execution time of 0.02 seconds, making it suitable for real-time applications.

Printed Graphene Electrochemical Biosensors Fabricated by Inkjet Maskless Lithography for Rapid and Sensitive Detection of Organophosphates.

Solution phase printing of graphene-based electrodes has recently become an attractive low-cost, scalable manufacturing technique to create in-field electrochemical biosensors. Here, we report a graphene-based electrode developed via inkjet maskless lithography (IML) for the direct and rapid monitoring of triple-O linked phosphonate organophosphates (OPs); these constitute the active compounds found in chemical warfare agents and pesticides that exhibit acute toxicity as well as long-term pollution to soils and waterways. The IML-printed graphene electrode is nano/microstructured with a 1000 mW benchtop laser engraver and electrochemically deposited platinum nanoparticles (dia. ∼25 nm) to improve its electrical conductivity (sheet resistance decreased from ∼10 000 to 100 Ω/sq), surface area, and electroactive nature for subsequent enzyme functionalization and biosensing. The enzyme phosphotriesterase (PTE) was conjugated to the electrode surface via glutaraldehyde cross-linking. The resulting biosensor was able to rapidly measure (5 s response time) the insecticide paraoxon (a model OP) with a low detection limit (3 nM), and high sensitivity (370 nA/μM) with negligible interference from similar nerve agents. Moreover, the biosensor exhibited high reusability (average of 0.3% decrease in sensitivity per sensing event), stability (90% anodic current signal retention over 1000 s), longevity (70% retained sensitivity after 8 weeks), and the ability to selectively sense OP in actual soil and water samples. Hence, this work presents a scalable printed graphene manufacturing technique that can be used to create OP biosensors that are suitable for in-field applications as well as, more generally, for low-cost biosensor test strips that could be incorporated into wearable or disposable sensing paradigms.

Optical and electrochemical detection of a verotoxigenic E. coli gene using DNAzyme-labeled stem-loops

The activity of a peroxidase-mimicking DNAzyme was optimized to be used as a catalytic label in a stem-loop genosensor construction for quantifying the gene sequence Shiga-like toxin I of verotoxigenic E. coli. Experimental conditions such as pH, buffer composition, potassium ion concentration, and hemin-to-oligonucleotides ratio, were analyzed to maximize optical and electrochemical responses using microvolumes. Different stem-loop constructions were evaluated to obtain the optimum response against the target concentration. Linear ranges of 0.05-0.5 µM and limits of detection of 174 nM and 144 nM were estimated for the optical and electrochemical measurements, respectively. Selectivity was proved by assaying other verotoxigenic, enterotoxigenic and enteroinvasive sequences. The results show that, if a combination of small-volume electrochemical cells and low-cost untreated screen-printed electrodes with a relatively high geometric area is used, electrochemical measurements present similar sensitivity and limits of detection to the more usual optical ones, allowing the development of low-cost electrochemical biosensors based on the use of soluble DNAzymes as labels.

Carbon paste electrode based on functional GOx/silica-lignin system to prepare an amperometric glucose biosensor

In this paper, a novel procedure for receiving enzyme biosensor based on the cheap and functional silica/lignin (SiO2/Lig) hybrid material is presented. In this study, a functional biohybrid SiO2/Lig was selected to conduct the immobilization of glucose oxidase (GOx) by adsorption on its surface. The immobilized amount of GOx at SiO2/Lig was 25.28mgg−1, twice as much compared to its amount at non-functionalized SiO2. The system of GOx-SiO2/Lig was combined with single-walled carbon nanotubes/platinum nanoparticles support to prepare a I generation glucose biosensor. Moreover, the GOx-SiO2/Lig based carbon paste electrode with ferrocene redox mediator was evaluated as an active material in II generation glucose biosensor. The GOx-SiO2/Lig/CPE was subjected to an examination in glucose solution by electrochemical techniques such as cyclic voltammetry (CV) and chronoamperometry. The obtained results suggest that GOx-SiO2/Lig can be a material of choice for preparation of an efficient and low-cost biosensor working in various electrode configurations. The newly obtained glucose biosensor presents promising electrochemical parameters for glucose determination. The glucose-sensing sensitivity amounted 0.78μAmM−1. The biosensor showed a linear response range of 0.5–9mM with a detection limit (LOD) of 145μM.

Fabrication of cobalt ferrite/cobalt sulfide hybrid nanotubes with enhanced peroxidase-like activity for colorimetric detection of dopamine

The development of highly sensitive and low-cost biosensors for the detection of dopamine is of paramount importance for medical diagnostics. Herein, we report the preparation of a new peroxidase-like catalyst with a uniform heterostructure by using a technique involving electrospinning, annealing and solvothermal reaction. In this catalyst system, cobalt sulfide (CoS) nanoparticles were homogenously distributed and supported on the surface of cobalt ferrite (CoFe2O4) nanotubes. The as-prepared CoFe2O4/CoS hybrid nanotubes showed remarkably high catalytic efficiency as peroxidase mimics toward the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of H2O2. Owing to the synergistic effect between the CoFe2O4 and CoS component, the prepared CoFe2O4/CoS hybrid nanotubes exhibited enhanced peroxidase-like activity, exceeding that of either the CoS nanoparticles or CoFe2O4 nanotubes alone. Dopamine has been widely investigated due to its unique function in the nervous system. Consequently, various approaches have been developed for the sensitive determination of dopamine. In this work, a simple and sensitive colorimetric route for the detection of dopamine was established based on the ability of dopamine to induce the reduction of oxidized TMB to TMB with consequent fading of the blue color. This method shows a wide linear range (0–50μM) and a low detection limit of 0.58μM. The unique heterostructure with spinel/sulfide interfaces represents a new concept for the construction of highly efficient and multifunctional biocatalysts.

Highly Sensitive Detection of Protein Biomarkers with Organic Electrochemical Transistors.

The analysis of protein biomarkers is of great importance in the diagnosis of diseases. Although many convenient and low-cost electrochemical approaches have been extensively investigated, they are not sensitive enough in the detection of protein biomarkers with low concentrations in physiological environments. Here, this study reports a novel organic-electrochemical-transistor-based biosensor that can successfully detect cancer protein biomarkers with ultrahigh sensitivity. The devices are operated by detecting electrochemical activity on gate electrodes, which is dependent on the concentrations of proteins labeled with catalytic nanoprobes. The protein sensors can specifically detect a cancer biomarker, human epidermal growth factor receptor 2, down to the concentration of 10-14 g mL-1 , which is several orders of magnitude lower than the detection limits of previously reported electrochemical approaches. Moreover, the devices can successfully differentiate breast cancer cells from normal cells at various concentrations. The ultrahigh sensitivity of the protein sensors is attributed to the inherent amplification function of the organic electrochemical transistors. This work paves a way for developing highly sensitive and low-cost biosensors for the detection of various protein biomarkers in clinical analysis in the future.

Transport of melamine by a new generation of nano-material membranes containing carbon nanotubes and determination with surface plasmon resonance

This study developed a surface plasmon resonance process for the determination of melamine by using a carbon nanotube inclusion polymeric membrane for the first time in the literature. It was prepared with a low-cost biosensor, which allowed the determination of melamine by molecular imprinted polymeric films in a one-step, selective, and sensitive way. For this purpose, the molecular imprinted sensors intended for the determination of melamine from a milk sample were developed. The study was achieved in three stages. In the first stage, melamine was transported by a new generation of carbon nanotube membrane, which was improved by adding nanomaterials. In the second stage, printed biosensor chips were produced for the determination of melamine. In the last stage, prepared biosensor chips were used for the determination and kinetic analysis of melamine in a surface plasmon resonance system. Melamine was transported from the milk sample with 82.87% efficiency at the end of ten days. The determination of melamine was achieved in a highly sensitive, selective, and easy way by preparing a melamine printed polymer nanofilm layer on the surface of the SPR's sensor chip. By using new generation carbon nanotube membranes (CNT/PIM), nano-reinforced membranes were developed, which included high permeability and mechanical strength against contamination, and the fulfill an active layer of the membrane was minimized.