Publications by authors named "Lars Laurentius"

Article Synopsis
  • Tuberculosis (TB) remains a significant global health issue, with millions of new cases each year, largely hindered by the lack of affordable, point-of-care diagnostic tests.
  • Researchers have been exploring mannose-capped lipoarabinomannan (ManLAM), a TB biomarker, but its detection has been challenging due to interference from other components in body fluids.
  • Recent advancements include developing an automated microfluidic platform that simplifies the sample pretreatment process for ManLAM, achieving similar recovery rates as traditional methods, and plans to integrate it with a portable reader for TB diagnostics.
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This paper reports on an investigation of an enzymatic pretreatment protocol using proteinase K (ProK) for the analysis of human serum samples spiked with mannose-capped lipoarabinomannan (ManLAM). ManLAM is an antigenic biomarker found in the serum, urine, and other body fluids of individuals infected with tuberculosis (TB). Immunometric measurements of ManLAM are compromised by steric effects due to its complexation with high-molecular-weight components in these matrices that interfere with its capture and/or labeling.

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A novel glucose sensor is presented using smart hydrogels as biocompatible implantable sensing elements, which eliminates the need for implanted electronics and uses an external medical-grade ultrasound transducer for readout. The readout mechanism uses resonance absorption of ultrasound waves in glucose-sensitive hydrogels. glucose concentration changes in the interstitial fluid lead to swelling or deswelling of the gels, which changes the resonance behavior.

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One of the main challenges for implantable biomedical sensing schemes is obtaining a reliable signal while maintaining biocompatibility. In this work, we demonstrate that a combination of medical ultrasound imaging and smart hydrogel micromechanical resonators can be employed for continuous monitoring of analyte concentrations. The sensing principle is based on the shift of the mechanical resonance frequencies of smart hydrogel structures induced by their volume-phase transition in response to changing analyte levels.

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The development of an accurate and rapid diagnostic test for tuberculosis (TB) to use at point of need is vital to efforts aimed at reducing the global burden from this disease. This paper builds on our previous studies of mannose-capped lipoarabinomannan (ManLAM) as a serum biomarker for active TB infection by means of a heterogeneous immunoassay. That work found that complexation with components in serum (e.

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TB diagnosis and treatment monitoring in resource limited regions rely heavily on serial sputum smear microscopy and bacterial culture. These microbiological methods are time-consuming, expensive and lack adequate sensitivity. The WHO states that improved TB diagnosis and treatment is imperative to achieve an end to the TB epidemic by 2030.

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Techniques for the detection of disease biomarkers are key components in the protection of human health. While work over the last few decades has redefined the low-level measurement of disease biomarkers, the translation of these capabilities from the formal clinical setting to point-of-need (PON) usage has been much more limited. This paper presents the results of experiments designed to examine the potential utility of a handheld Raman spectrometer as a PON electronic reader for a sandwich immunoassay based on surface-enhanced Raman scattering (SERS).

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Patient care and prevention of disease outbreaks rely heavily on the performance of diagnostic tests. These tests are typically carried out in serum, urine, and other complex sample matrices, but are often plagued by a number of matrix effects such as nonspecific adsorption and complexation with circulating proteins. This paper demonstrates the importance of sample pretreatment to overcome matrix effects, enabling the low-level detection of a disease marker for tuberculosis (TB).

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The ability to detect tuberculosis (TB) continues to be a global health care priority. This paper describes the development and preliminary assessment of the clinical accuracy of a heterogeneous immunoassay that integrates a serum pretreatment process with readout by surface-enhanced Raman scattering (SERS) for the low-level detection of mannose-capped lipoarabinomannan (ManLAM). ManLAM is a major virulence factor in the infectious pathology of Mycobacterium tuberculosis (Mtb) that has been found in the serum and other body fluids of infected patients.

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Introduction: Nanoparticle-based disease diagnostics harness a range of unique physical and chemical phenomena for the detection of biomarkers at exceedingly low levels. This capability potentially enables the diagnosis of disease earlier in its progression and improves the likelihood of positive treatment outcomes. This review highlights recent work in this area, and then projects the next steps needed to move this emerging capability beyond the research laboratory.

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Tailoring the surface chemistry of metallic nanoparticles is generally a key step for their use in a wide range of applications. There are few examples of organic films covalently bound to metal nanoparticles. We demonstrate here that aryl films are formed on gold nanoparticles from the spontaneous reduction of diazonium salts.

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