Membrane Sensor Research Articles

Eu3+ embedded hybrid fluorescent membrane for Ultrasensitive and efficient sensing of Cu2+ in aqueous media

Copper (Cu2+) detection is of great significance as it is important constituent of human body and its excessive amount may cause the neurodegenerative diseases. Herein, we developed fluorogenic indicator Eu3+ complex (Eu(TTA)3phen) embedded a novel polyvinylidene fluoride (PVDF)/polyvinylpyrrolidone (PVP) hybrid fibrous membrane (HFM), prepared via electrospinning technique, for the Cu2+ detection in the aqueous media. Compared with conventional pristine PVDF membrane, the current PVDF/PVP hybrid flexible fibrous membrane exhibited improved hydrophilicity (contact angle decreased from 135° to 33°), which was attributed to uniformly dispersed PVP. Scanning electron microscopic study confirmed the bead like nanofibrous morphology of electrospun Eu(TTA)3phen doped PVDF/PVP hybrid membrane. The devised nanofibrous membrane exhibited a fast response and good selectivity and sensitivity towards Cu2+, almost no response was observed for other ions. Efficient fluorescence quenching was observed upon addition of Cu2+ ions onto the membrane owing to the interruption of antenna affect from ligand to Eu3+. The current nanofibrous membrane sensor allowed the Cu2+ detection in the range of 2.5–30 μM, with a detection limit of 4.47 μM in aqueous media, demonstrating its potential for use in the clinical test of neurodegenerative diseases.

Tailored diffusion limiting membrane for microneedle glucose sensors with wide linear range

Continuous glucose monitoring is very important to daily blood glucose control in diabetic patients, but its accuracy is limited by the narrow linear range of the response of biosensor to the glucose concentration because of the oxygen starvation in tissue and the limited maximum conversion rate of glucose oxidase. In this work, a biocompatible diffusion limiting membrane based on two medical-grade polyurethanes is developed via blending modification to restrict the diffusion flux of glucose to match the oxygen concentration and the maximum conversion rate. The expansiveness of the linear range for the nanomaterials-modified electrode in the glucose biosensor can be achieved through the regulation of two polyurethanes, the solvent, and the thickness of the membrane. In addition, the mass transport of hydrogen peroxide and interfering substances is also limited of the membrane. The in vitro experiments demonstrated that the membrane-modified microneedle biosensor exhibited a rapid response to the concentration variation of glucose, a wide linear range that is sufficient to cover the blood concentration of healthy and diabetic people, the ability to resist the oxygen concentration fluctuation and interfering substances, good reproducibility and long-term stability. The custom wearable electrochemical system, possessing these characteristics, has been proven to accurately monitor the blood concentration in a living rat in real time. This demonstrates a significant potential for application in both daily and clinical blood glucose monitoring.

Portably and Visually Sensing Cytisine through Smartphone Scanning Based on a Post‐Modified Luminescence Center Strategy in Zinc‐Organic Frameworks

AbstractCytisine (CTS) is a useful medicine for treating nervous disorders and smoking addiction, and exploring a convenient method to detect CTS is of great significance for long‐term/home medication to avoid the risk of poisoning, but it is full of challenges. Here, a modified metal–organic framework sensor Tb@Zn‐TDA‐80 with dual emission centers was prepared using a post‐modified luminescence center strategy. The obtained Tb@Zn‐TDA‐80 can serve as a CTS sensor with high sensitivity and selectivity. To achieve portable detection, Tb@Zn‐TDA‐80 was further fabricated as a membrane sensor, M−Tb@Zn‐TDA‐80, which displayed an obvious CTS‐responsive color change by simply dropping a CTS solution onto its surface. Benefiting from this unique functionality, M−Tb@Zn‐TDA‐80 successfully realized the visual detection and quantitative monitoring of CTS in the range of 5.26–52.6 mM by simply scanning the color with a smartphone. The results of nuclear magnetic resonance spectroscopy and theoretical computation illustrated that the high sensing efficiency of Tb@Zn‐TDA‐80 for CTS was attributed to the N−H⋅⋅⋅π and π⋅⋅⋅π interactions between the ligand and CTS. And luminescence quenching may result from the intramolecular charge transfer. This study provides a convenient method for ensuring long‐term medication safety at home.

Portably and Visually Sensing Cytisine through Smartphone Scanning Based on a Post-Modified Luminescence Center Strategy in Zinc-Organic Frameworks.

Cytisine (CTS) is a useful medicine for treating nervous disorders and smoking addiction, and exploring a convenient method to detect CTS is of great significance for long-term/home medication to avoid the risk of poisoning, but it is full of challenges. Here, a modified metal-organic framework sensor Tb@Zn-TDA-80 with dual emission centers was prepared using a post-modified luminescence center strategy. The obtained Tb@Zn-TDA-80 can serve as a CTS sensor with high sensitivity and selectivity. To achieve portable detection, Tb@Zn-TDA-80 was further fabricated as a membrane sensor, M-Tb@Zn-TDA-80, which displayed an obvious CTS-responsive color change by simply dropping a CTS solution onto its surface. Benefiting from this unique functionality, M-Tb@Zn-TDA-80 successfully realized the visual detection and quantitative monitoring of CTS in the range of 5.26-52.6 mM by simply scanning the color with a smartphone. The results of nuclear magnetic resonance spectroscopy and theoretical computation illustrated that the high sensing efficiency of Tb@Zn-TDA-80 for CTS was attributed to the N-H⋅⋅⋅π and π⋅⋅⋅π interactions between the ligand and CTS. And luminescence quenching may result from the intramolecular charge transfer. This study provides a convenient method for ensuring long-term medication safety at home.

Effect of nanoporous membranes thickness in electrochemical biosensing performance: application for the detection of a wound infection biomarker.

Introduction: Nanoporous alumina membranes present a honeycomb-like structure characterized by two main parameters involved in their performance in electrochemical immunosening: pore diameter and pore thickness. Although this first one has been deeply studied, the effect of pore thickness in electrochemical-based nanopore immunosensors has been less taken into consideration. Methods: In this work, the influence of the thickness of nanoporous membranes in the steric blockage is studied for the first time, through the formation of an immunocomplex in their inner walls. Finally, the optimal nanoporous membranes were applied to the detection of catalase, an enzyme related with chronic wound infection and healing. Results: Nanoporous alumina membranes with a fixed pore diameter (60 nm) and variable pore thicknesses (40, 60, 100 μm) have been constructed and evaluated as immunosensing platform for protein detection. Our results show that membranes with a thickness of 40 μm provide a higher sensitivity and lower limit-of-detection (LOD) compared to thicker membranes. This performance is even improved when compared to commercial membranes (with 20 nm pore diameter and 60 μm pore thickness), when applied for human IgG as model analyte. A label-free immunosensor using a monoclonal antibody against anti-catalase was also constructed, allowing the detection of catalase in the range of 50-500 ng/mL and with a LOD of 1.5 ng/mL. The viability of the constructed sensor in real samples was also tested by spiking artificial wound infection solutions, providing recovery values of 110% and 118%. Discussion: The results obtained in this work evidence the key relevance of the nanochannel thickness in the biosensing performance. Such findings will illuminate nanoporous membrane biosensing research, considering thickness as a relevant parameter in electrochemical-based nanoporous membrane sensors.

Using Rapid Prototyping to Develop a Cell-Based Platform with Electrical Impedance Sensor Membranes for In Vitro RPMI2650 Nasal Nanotoxicology Monitoring.

Due to advances in additive manufacturing and prototyping, affordable and rapid microfluidic sensor-integrated assays can be fabricated using additive manufacturing, xurography and electrode shadow masking to create versatile platform technologies aimed toward qualitative assessment of acute cytotoxic or cytolytic events using stand-alone biochip platforms in the context of environmental risk assessment. In the current study, we established a nasal mucosa biosensing platform using RPMI2650 mucosa cells inside a membrane-integrated impedance-sensing biochip using exclusively rapid prototyping technologies. In a final proof-of-concept, we applied this biosensing platform to create human cell models of nasal mucosa for monitoring the acute cytotoxic effect of zinc oxide reference nanoparticles. Our data generated with the biochip platform successfully monitored the acute toxicity and cytolytic activity of 6 mM zinc oxide nanoparticles, which was non-invasively monitored as a negative impedance slope on nasal epithelial models, demonstrating the feasibility of rapid prototyping technologies such as additive manufacturing and xurography for cell-based platform development.

Pseudomonas aeruginosa MipA-MipB envelope proteins act as new sensors of polymyxins.

Due to the rising incidence of antibiotic-resistant infections, the last-line antibiotics, polymyxins, have resurged in the clinics in parallel with new bacterial strategies of escape. The Gram-negative opportunistic pathogen Pseudomonas aeruginosa develops resistance to colistin/polymyxin B by distinct molecular mechanisms, mostly through modification of the lipid A component of the LPS by proteins encoded within the arnBCDATEF-ugd (arn) operon. In this work, we characterized a polymyxin-induced operon named mipBA, present in P. aeruginosa strains devoid of the arn operon. We showed that mipBA is activated by the ParR/ParS two-component regulatory system in response to polymyxins. Structural modeling revealed that MipA folds as an outer-membrane β-barrel, harboring an internal negatively charged channel, able to host a polymyxin molecule, while the lipoprotein MipB adopts a β-lactamase fold with two additional C-terminal domains. Experimental work confirmed that MipA and MipB localize to the bacterial envelope, and they co-purify in vitro. Nano differential scanning fluorimetry showed that polymyxins stabilized MipA in a specific and dose-dependent manner. Mass spectrometry-based quantitative proteomics on P. aeruginosa membranes demonstrated that ∆mipBA synthesized fourfold less MexXY-OprA proteins in response to polymyxin B compared to the wild-type strain. The decrease was a direct consequence of impaired transcriptional activation of the mex operon operated by ParR/ParS. We propose MipA/MipB to act as membrane (co)sensors working in concert to activate ParS histidine kinase and help the bacterium to cope with polymyxin-mediated envelope stress through synthesis of the efflux pump, MexXY-OprA.IMPORTANCEDue to the emergence of multidrug-resistant isolates, antibiotic options may be limited to polymyxins to eradicate Gram-negative infections. Pseudomonas aeruginosa, a leading opportunistic pathogen, has the ability to develop resistance to these cationic lipopeptides by modifying its lipopolysaccharide through proteins encoded within the arn operon. Herein, we describe a sub-group of P. aeruginosa strains lacking the arn operon yet exhibiting adaptability to polymyxins. Exposition to sub-lethal polymyxin concentrations induced the expression and production of two envelope-associated proteins. Among those, MipA, an outer-membrane barrel, is able to specifically bind polymyxins with an affinity in the 10-µM range. Using membrane proteomics and phenotypic assays, we showed that MipA and MipB participate in the adaptive response to polymyxins via ParR/ParS regulatory signaling. We propose a new model wherein the MipA-MipB module functions as a novel polymyxin sensing mechanism.

Influence of en-APTAS membrane on NO gas selectivity of HfO2-based memristor gas sensors

Memristor-based gas sensors (gas sensor + memristor, gasistor) have gained popularity due to their high response characteristics and ability to operate at RT. In this paper, N-[3-(Trimethoxysilyl)propyl]ethylenediamine (en-APTAS), a commonly used membrane for NO x gas sensors, is applied in the gasistor with carbon nanotubes (CNTs)-top electrode (TE). As a result, we have demonstrated the response time was reduced by 104 s, and the response to 10 ppm Nitric oxide (NO) gas increased to 3.69, indicating an enhanced sensing property in a range of 10–50 ppm. Furthermore, when decorated with the proposed en-APTAS, the gasistor with CNTs-TE demonstrated a 3.76-fold increase in response to NO gas compared to NO2 gas, demonstrating remarkable selectivity. These improved features are attributed to the high adsorption energy of en-APTAS and the large kinetic diameter of NO2. The research proposal will be a foundational stage towards attaining selectivity in other gasistor studies.

Poly(vinyl chloride)/Nanocarbon Composites for Advanced Potentiometric Membrane Sensor Design.

Polymer nanocomposites filled with carbon nanoparticles (CNPs) are a hot topic in materials science. This article discusses the current research on the use of these materials as interfacial electron transfer films for solid contact potentiometric membrane sensors (SC-PMSs). The results of a comparative study of plasticized poly (vinyl chloride) (pPVC) matrices modified with single-walled carbon nanotubes (SWCNTs), fullerenes-C60, and their hybrid ensemble (SWCNTs-C60) are reported. The morphological characteristics and electrical conductivity of the prepared nanostructured composite films are reported. It was found that the specific electrical conductivity of the pPVC/SWCNTs-C60 polymer film was higher than that of pPVC filled with individual nanocomponents. The effectiveness of this composite material as an electron transfer film in a new potentiometric membrane sensor for detecting phenylpyruvic acid (in anionic form) was demonstrated. Screening for this metabolic product of phenylalanine in body fluids is of significant diagnostic interest in phenylketonuria (dementia), viral hepatitis, and alcoholism. The developed sensor showed a stable and fast Nernstian response for phenylpyruvate ions in aqueous solutions over the wide linear concentration range of 5 × 10-7-1 × 10-3 M, with a detection limit of 10-7.2 M.

Ionophore-based potentiometric PVC membrane sensors for the determination of moxifloxacin

Ionophore-based potentiometric PVC membrane sensors for the determination of moxifloxacin

Comparative analysis for strain response and life monitoring of composite using carbon-based nanosensors

Sensing technology based on carbon nanomaterials has become a very promising technology in the field of composite health monitoring, which requires high-sensitivity piezoresistive strain sensors to serve. In this study, two different carbon nano-sensors were used. Based on the traditional carbon nano-paper sensor, a flexible printed circuit and a polysulfone membrane were added to ensure the stability and sensitivity of the sensor. The conductive mechanism of adjacent carbon nanotubes (CNT) was analyzed. The electrical network model inside the carbon nanosensor was established, and its working mechanism during loading and unloading was described. The research mainly adopts three-point bending experiment. The deformation and failure of composite laminates containing two kinds of sensors under load experience low strain and high strain cyclic loading. Both sensors have the same response and stability as the load growth trend. Experiments show that the CNT-Paper sensor is suitable for long-term health monitoring of composite materials. The carbon nanotube-ultrafiltration membrane (CNT-UM) sensor is more sensitive to the cyclic monitoring of small strain.

Sterilization effects on nitric oxide-releasing glucose sensors

Nitric oxide (NO) release from S-nitrosothiol-modified mesoporous silica nanoparticles imbedded in the diffusion limiting layer of a glucose sensor has been demonstrated as an effective strategy for mitigating the foreign body response common to sensor implantation, resulting in improved analytical performance. With respect to potential clinical translation of this approach, the effects of sterilization on NO-releasing biosensors require careful evaluation, as NO donor chemistry is sensitive to temperature and environment. Herein, we evaluated the influence of multiple sterilization methods on 1) sterilization success; 2) NO payload; and 3) sensor performance to establish the commercialization potential of NO-releasing glucose sensors. Sensors were treated with ethylene oxide gas, the most common sterilization method for intricate medical devices, which led to undesirable (i.e., premature) release of NO. To reduce NO loss, alternative sterilization methods that were studied included exposure to ultraviolet (UV) light and immersion in 70 % ethanol (EtOH). Sterilization cycle times required to reach a 10−6 sterility assurance level were determined for both UV light and 70 % EtOH against Gram-negative and -positive bacteria. The longest sterilization cycle times (258 s and 628 s for 70 % EtOH and UV light, respectively) resulted in a negligible impact on benchtop sensor performance. However, sterilization with 70 % ethanol resulted in a reduced NO-release duration. Ultraviolet light exposure for ∼10 min proved successful at eliminating bacteria without compromising NO payloads or durations and presents as the most promising method for sterilization of these sensors. In addition, storage of NO-releasing sensor membranes at –20 and –80 °C resulted in preservation of NO release for 6 and 12 months, respectively.

Stability-indicating determination of ciprofloxacin in the presence of its main photo-degradation product using solid-contact electrodes in river water

The application of membrane sensors for monitoring and evaluation of pharmaceutical environmental contaminants has become a significant aim in the past few years. Due to the wide applicability of ciprofloxacin hydrochloride (CPF) in medicine, there is a high probability of its presence in the environment, especially in surface water like river water. The long-term exposure of the river water to sunlight and the photoliability of CPF may increase its photo-degradation. Two selective and sensitive membrane electrodes were created to measure CPF when it is present with its main photo-degradant product. These were made using two ion pairing agents, which are sodium tetraphenylborate (TPB) and phosphotungstic acid (PTA). The linearity range of the manufactured electrodes was 1 × 10-6–1 × 10-2 M. The slopes of the CPF-TPB and CPF-PTA membrane electrodes are 60.1 ± 0.70 and 57.9 ± 0.90 mV/decade, respectively. The cited sensors showed adequate performance in a pH range from 2.0 to 5.0. All test parameters were fine-tuned to provide the best electrochemical performance. The manufactured membranes were successfully used to determine CPF in a sensitive way in the presence of its primary photodegradant. The cited sensors were effectively used to quantify CPF in river water samples, with no pre-treatment operations required.

Conductive imprinted polymeric interfacially modified electrochemical sensors based on covalently bonded layer-by-layer assembly of Gr/Au with flower-like morphology for sensitive detection of 2,4,6-TCP.

Polymeric membrane sensors based on molecular imprinted polymers (MIPs) have been attractive analytical tools for detecting organic species. However, the MIPs in electrochemical sensors developed so far are usually prepared by in situ polymerization of pre-polymers and non-covalent adsorption on the surface of the working electrode. Meanwhile, the MIPs in the electrochemical sensors developed are typically made of a non-conductive polymer film. This results in a relatively low current due to the lack of electron transfer. Additionally, the smoothness of the traditional electrochemical substrate results in a low specific surface area, which reduces the sensitivity of the electrochemical sensor. Here, we describe a novel electrochemical sensor with a conductive interface and MIPs modification. The electrochemical sensor was modified by covalent coupled layer by layer self-assembly with the imprinted polymer film. The incorporation of these two conductive functional materials improves the conductivity of the electrodes and provides interface support materials to obtain high specific surface area. By using 2,4,6-trichlorophenol as the model, the sensitivity of the developed conductive sensor was greatly improved compared to that of the traditional MIPs sensor. We believe that the proposed MIPs-based sensing strategy provides a general and convenient method for making sensitive and selective electrochemical sensors.

Fabrication of a novel palladium membrane sensor for its determination in environmental and biological samples

A novel sensitive, specific, and reversible optical sensor for the palladium(ii) ion was created by impregnating an agarose membrane with 4-(2-amino-3-hydroxypyridine-4-ylazo)1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one (AHDDO).

Optimization of innovative optical sensor for zirconium determination and capturing from environmental samples

A highly sensitive bulk optode membrane, specifically engineered for the identification of zirconyl (ZrO2+) ions, has been successfully created. The membrane is composed of plasticized polyvinyl chloride (PVC), dibenzodylmethane (DBM) acting as the chromoionophore, 2-amino-4-(3-chlorophenylazo)pyridine-3-ol (ACPAP) serving as the ionophore, and sodium tetraphenylborate (NaTPB) included as an ionic additive. The sensing membrane undergoes a color change from orange to blue when exposed to ZrO2+ ions at pH 6.5. The preparation parameters of the sensor and the determination of ZrO2+ ions were meticulously optimized. In addition to showcasing reproducibility, extended stability, and a comparatively long lifespan, the suggested sensor membrane displays remarkable selectivity for ZrO2+ ions, effectively discerning them from a spectrum of alkaline earth, heavy and transition metal ions, and actinides. The sensor delivers a calibration response tailored for ZrO2+ ions across a concentration spectrum spanning 7.5–185 ng mL−1, establishing limits of quantification and detection at 7.3 and 2.2 ng mL−1, respectively. Demonstrating a rapid response within a timeframe of under 5.0 min. The sensor consistently delivered highly reproducible results, as evidenced by relative standard deviation (RSD) of 1.67 % and 1.55 % for Zr4+ concentrations at 100 and 150 ng mL−1.This underscores the precision and reliability of the sensor. Regeneration of the optode can be easily accomplished by employing 0.05 M HCl. Effectively employed across a spectrum of samples, including water, soil, plant materials, and ore solutions, the proposed optical sensor proves to be a valuable instrument for determining ZrO2+ ions in diverse environmental and analytical scenarios.

Detection of Hexavalent Chromium Ion in Water by Optode Membrane

Chromium is a heavy metal that is often found as a water pollutant. High concentrations of hexavalent chromium (Cr(VI)) ion in nature are toxic and carcinogenic, so their presence in water needs to be monitored. Detection of heavy metals in water was carried out using an optical sensor membrane (optode). The optode was fabricated from cellulose triacetate polymer with plasticizers (oleic acid and acetophenone), aliquot 336, and the chromoionophore 1.5-diphenylcarbazide (DPC). The success synthesis of optode was evidenced by FTIR and SEM characterization. The optode performance produces a linear response in detecting Cr(VI) ion in the concentration range of 0.02-0.40 mg/L with an R2 of 0.9930, as well as the best conditioning at pH 3. The detection and quantitation limits are 0.0055 mg/L and 0.0165 mg/L. The sensitivity of the chromium optode was excellence, with a molar absorptivity value of 8.8303 × 106 M-1cm-1. The performance test results of the chromium optode were acceptable because they meet the specified requirements for minimum detection concentration value.

Analytical Analysis of Flexible Microfluidic Based Pressure Sensor Based on Triple-Channel Design

In designing a flexible microfluidic-based pressure sensor, the microchannel plays an important role in maximizing the sensor's performance. Similarly, the material used for the sensor's membrane is crucial in achieving optimal performance. This study presents an analytical analysis and FEA simulation of the membrane and microchannel of the flexible pressure sensor, aimed at optimizing it design and material selection. Different types of materials, including two commonly used polymers, Polyimide (PI) and Polydimethylsiloxane (PDMS) were evaluated. Moreover, different designs of the microchannel, including single-channel, double-channel, and triple-channel, were analyzed. The applied pressure, width of the microchannel, and length of the microchannel were varied to study the normalized resistance of the microchannel and maximize the performance of the pressure sensor. The results showed that the triple-channel design produced the highest normalized resistance. To achieve maximum performance, it is found that using a membrane with a large area facing the applied pressure was optimal in terms of dimensions. In conclusion, optimizing the microchannel and membrane design and material selection is crucial in improving the overall performance of flexible microfluidic-based pressure sensors.

Single-Ion Counting with an Ultra-Thin-Membrane Silicon Carbide Sensor.

In recent times, ion implantation has received increasing interest for novel applications related to deterministic material doping on the nanoscale, primarily for the fabrication of solid-state quantum devices. For such applications, precise information concerning the number of implanted ions and their final position within the implanted sample is crucial. In this work, we present an innovative method for the detection of single ions of MeV energy by using a sub-micrometer ultra-thin silicon carbide sensor operated as an in-beam counter of transmitted ions. The SiC sensor signals, when compared to a Passivated Implanted Planar Silicon detector signal, exhibited a 96.5% ion-detection confidence, demonstrating that the membrane sensors can be utilized for high-fidelity ion counting. Furthermore, we assessed the angular straggling of transmitted ions due to the interaction with the SiC sensor, employing the scanning knife-edge method of a focused ion microbeam. The lateral dimension of the ion beam with and without the membrane sensor was compared to the SRIM calculations. The results were used to discuss the potential of such experimental geometry in deterministic ion-implantation schemes as well as other applications.

Specific Cationic Antimicrobial Peptides Enhance the Recovery of Low-Load Quiescent Mycobacterium tuberculosis in Routine Diagnostics.

The culture confirmation of Mycobacterium tuberculosis (MTB) remains the gold standard for the diagnosis of Tuberculosis (TB) with culture conversion representing proof of cure. However, over 40% of TB samples fail to isolate MTB even though many patients remain infectious due to the presence of viable non-culturable forms. Previously, we have shown that two short cationic peptides, T14D and TB08L, induce a hormetic response at low concentrations, leading to a stimulation of growth in MTB and the related animal pathogen Mycobacterium bovis (bTB). Here, we examine these peptides showing they can influence the mycobacterial membrane integrity and function through membrane potential reduction. We also show this disruption is associated with an abnormal reduction in transcriptomic signalling from specific mycobacterial membrane sensors that normally monitor the immediate cellular environment and maintain the non-growing phenotype. We observe that exposing MTB or bTB to these peptides at optimal concentrations rapidly represses signalling mechanisms maintaining dormancy phenotypes, which leads to the promotion of aerobic metabolism and conversion into a replicative phenotype. We further show a practical application of these peptides as reagents able to enhance conventional routine culture methods by stimulating mycobacterial growth. We evaluated the ability of a peptide-supplemented sample preparation and culture protocol to isolate the MTB against a gold standard routine method tested in parallel on 255 samples from 155 patients with suspected TB. The peptide enhancement increased the sample positivity rate by 46% and decreased the average time to sample positivity of respiratory/faecal sampling by seven days. The most significant improvements in isolation rates were from sputum smear-negative low-load samples and faeces. The peptide enhancement increased sampling test sensitivity by 19%, recovery in samples from patients with a previously culture-confirmed TB by 20%, and those empirically treated for TB by 21%. We conclude that sample decontamination and culture enhancement with D-enantiomer peptides offer good potential for the much-needed improvement of the culture confirmation of TB.