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Sarmad S, Viant MR, Dunn WB, Goodacre R, Wilson ID, Chappell KE, Griffin JL, O'Donnell VB, Naicker B, Lewis MR, Suzuki T. A proposed framework to evaluate the quality and reliability of targeted metabolomics assays from the UK Consortium on Metabolic Phenotyping (MAP/UK). Nat Protoc 2023; 18:1017-1027. [PMID: 36828894 DOI: 10.1038/s41596-022-00801-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 11/24/2022] [Indexed: 02/26/2023]
Abstract
Targeted metabolite assays that measure tens or hundreds of pre-selected metabolites, typically using liquid chromatography-mass spectrometry, are increasingly being developed and applied to metabolic phenotyping studies. These are used both as standalone phenotyping methods and for the validation of putative metabolic biomarkers obtained from untargeted metabolomics studies. However, there are no widely accepted standards in the scientific community for ensuring reliability of the development and validation of targeted metabolite assays (referred to here as 'targeted metabolomics'). Most current practices attempt to adopt, with modifications, the strict guidance provided by drug regulatory authorities for analytical methods designed largely for measuring drugs and other xenobiotic analytes. Here, the regulatory guidance provided by the European Medicines Agency, US Food and Drug Administration and International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use are summarized. In this Perspective, we have adapted these guidelines and propose a less onerous 'tiered' approach to evaluate the reliability of a wide range of metabolomics analyses, addressing the need for community-accepted, harmonized guidelines for tiers other than full validation. This 'fit-for-purpose' tiered approach comprises four levels-discovery, screening, qualification and validation-and is discussed in the context of a range of targeted and untargeted metabolomics assays. Issues arising with targeted multiplexed metabolomics assays, and how these might be addressed, are considered. Furthermore, guidance is provided to assist the community with selecting the appropriate degree of reliability for a series of well-defined applications of metabolomics.
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Affiliation(s)
- Sarir Sarmad
- Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Biomedical Research Centre, Leicester, UK
| | - Mark R Viant
- Phenome Centre Birmingham, University of Birmingham, Birmingham, UK
| | - Warwick B Dunn
- Centre for Metabolomics Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular, and Integrative Biology, University of Liverpool, Liverpool, UK.,Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Royston Goodacre
- Centre for Metabolomics Research, Department of Biochemistry and Systems Biology, Institute of Systems, Molecular, and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Ian D Wilson
- Division of Systems Medicine, Department of Metabolism, Digestion & Reproduction, Imperial College London, London, UK
| | - Katie E Chappell
- The National Phenome Centre, Department of Metabolism, Digestion & Reproduction, Imperial College London, London, UK
| | - Julian L Griffin
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Valerie B O'Donnell
- Systems Immunity Research Institute, School of Medicine, Cardiff University, Cardiff, UK
| | - Brendon Naicker
- Systems Immunity Research Institute, School of Medicine, Cardiff University, Cardiff, UK
| | - Matthew R Lewis
- The National Phenome Centre, Department of Metabolism, Digestion & Reproduction, Imperial College London, London, UK
| | - Toru Suzuki
- Department of Cardiovascular Sciences, University of Leicester and NIHR Leicester Biomedical Research Centre, Leicester, UK. .,The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
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Tukulula M, Gouveia L, Paixao P, Hayeshi R, Naicker B, Dube A. Functionalization of PLGA Nanoparticles with 1,3-β-glucan Enhances the Intracellular Pharmacokinetics of Rifampicin in Macrophages. Pharm Res 2018; 35:111. [PMID: 29600438 DOI: 10.1007/s11095-018-2391-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 03/19/2018] [Indexed: 11/28/2022]
Abstract
PURPOSE Mycobacterium tuberculosis which causes tuberculosis, is primarily resident within macrophages. 1,3-β-glucan has been proposed as a ligand to target drug loaded nanoparticles (NPs) to macrophages. In this study we characterized the intracellular pharmacokinetics of the anti-tubercular drug rifampicin delivered by 1,3-β-glucan functionalized PLGA NPs (Glu-PLGA). We hypothesized that Glu-PLGA NPs would be taken up at a faster rate than PLGA NPs, and consequently deliver higher amounts of rifampicin into the macrophages. METHODS Carbodiimide chemistry was employed to conjugate 1,3-β-glucan and rhodamine to PLGA. Rifampicin loaded PLGA and Glu-PLGA NPs as well as rhodamine functionalized PLGA and Glu-PLGA NPs were synthesized using an emulsion solvent evaporation technique. Intracellular pharmacokinetics of rifampicin and NPs were evaluated in THP-1 derived macrophages. A pharmacokinetic model was developed to describe uptake, and modelling was performed using ADAPT 5 software. RESULTS The NPs increased the rate of uptake of rifampicin by a factor of 17 and 62 in case of PLGA and Glu-PLGA, respectively. Expulsion of NPs from the macrophages was also observed, which was 3 fold greater for Glu-PLGA NPs than for PLGA NPs. However, the ratio of uptake to expulsion was similar for both NPs. After 24 h, the amount of rifampicin delivered by the PLGA and Glu-PLGA NPs was similar. The NPs resulted in at least a 10-fold increase in the uptake of rifampicin. CONCLUSIONS Functionalization of PLGA NPs with 1,3-β-glucan resulted in faster uptake of rifampicin into macrophages. These NPs may be useful to achieve rapid intracellular eradication of Mycobacterium tuberculosis.
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Affiliation(s)
| | - Luis Gouveia
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa,, Lisbon, Portugal
| | - Paulo Paixao
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa,, Lisbon, Portugal
| | - Rose Hayeshi
- DST/NWU Preclinical Drug Development Platform, North-West University,, Potchefstroom, South Africa
| | - Brendon Naicker
- Council for Scientific and Industrial Research, Polymers and Composites, Pretoria, South Africa
| | - Admire Dube
- Discipline of Pharmaceutics, School of Pharmacy, University of the Western Cape,, Bellville, 7535, South Africa.
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Gcebe N, Rutten VPMG, van Pittius NG, Naicker B, Michel AL. Mycobacterium komaniense sp. nov., a rapidly growing non-tuberculous Mycobacterium species detected in South Africa. Int J Syst Evol Microbiol 2018. [PMID: 29543151 DOI: 10.1099/ijsem.0.002707] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Some species of non-tuberculous mycobacteria (NTM) have been reported to be opportunistic pathogens of animals and humans. Recently there has been an upsurge in the number of cases of NTM infections, such that some NTM species are now recognized as pathogens of humans and animals. From a veterinary point of view, the major significance of NTM is the cross-reactive immune response they elicit against Mycobacterium bovis antigens, leading to misdiagnosis of bovine tuberculosis. Four NTM isolates were detected from a bovine nasal swab, soil and water, during an NTM survey in South Africa. These were all found using 16S rRNA gene sequence analysis to be closely related to Mycobacterium moriokaense. The isolates were further characterised by sequence analysis of the partial fragments of hsp65, rpoB and sodA. The genome of the type strain was also elucidated. Gene (16S rRNA, hsp65, rpoB and sodA) and protein sequence data analysis of 6 kDa early secretory antigenic target (ESAT 6) and 10 kDa culture filtrate protein (CFP-10) revealed that these isolates belong to a unique Mycobacterium species. Differences in phenotypic and biochemical traits between the isolates and closely related species further supported that these isolates belong to novel Mycobacterium species. We proposed the name Mycobacterium komaniense sp. nov. for this new species. The type strain is GPK 1020T (=CIP 110823T=ATCC BAA-2758).
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Affiliation(s)
- Nomakorinte Gcebe
- Tuberculosis Laboratory, Agricultural Research Council - Onderstepoort Veterinary Research, Onderstepoort, South Africa.,Department of Veterinary Tropical Diseases, Bovine Tuberculosis and Brucellosis Research Programme, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Victor P M G Rutten
- Department of Veterinary Tropical Diseases, Bovine Tuberculosis and Brucellosis Research Programme, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa.,Division of Immunology, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Nicolaas Gey van Pittius
- Centre of Excellence for Biomedical Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Brendon Naicker
- Polymers and Composites, Materials Science and Manufacturing, Council for Scientific and Industrial Research, Brummeria, South Africa
| | - Anita L Michel
- Department of Veterinary Tropical Diseases, Bovine Tuberculosis and Brucellosis Research Programme, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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Gcebe N, Rutten V, Pittius NGV, Naicker B, Michel A. Mycobacterium malmesburyense sp. nov., a non-tuberculous species of the genus Mycobacterium revealed by multiple gene sequence characterization. Int J Syst Evol Microbiol 2017; 67:832-838. [PMID: 27926825 DOI: 10.1099/ijsem.0.001678] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Non-tuberculous mycobacteria (NTM) are ubiquitous in the environment, and an increasing number of NTM species have been isolated and characterized from both humans and animals, highlighting the zoonotic potential of these bacteria. Host exposure to NTM may impact on cross-reactive immune responsiveness, which may affect diagnosis of bovine tuberculosis and may also play a role in the variability of the efficacy of Mycobacterium bovis BCG vaccination against tuberculosis. In this study we characterized 10 NTM isolates originating from water, soil, nasal swabs of cattle and African buffalo as well as bovine tissue samples. These isolates were previously identified during an NTM survey and were all found, using 16S rRNA gene sequence analysis to be closely related to Mycobacterium moriokaense. A polyphasic approach that included phenotypic characterization, antibiotic susceptibility profiling, mycolic acid profiling and phylogenetic analysis of four gene loci, 16S rRNA, hsp65, sodA and rpoB, was employed to characterize these isolates. Sequence data analysis of the four gene loci revealed that these isolates belong to a unique species of the genus Mycobacterium. This evidence was further supported by several differences in phenotypic characteristics between the isolates and the closely related species. We propose the name Mycobacterium malmesburyense sp. nov. for this novel species. The type strain is WCM 7299T (=ATCC BAA-2759T=CIP 110822T).
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Affiliation(s)
- Nomakorinte Gcebe
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Gauteng 0110, South Africa.,Tuberculosis Laboratory, Agricultural Research Council - Onderstepoort Veterinary Institute, Onderstepoort, Gauteng 0110, South Africa
| | - Victor Rutten
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Gauteng 0110, South Africa.,Department of Infectious Diseases and Immunology, Division of Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Nicolaas Gey van Pittius
- Centre of Excellence for Biomedical Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - Brendon Naicker
- Polymers and Composites, Materials Science and Manufacturing, Council for Scientific and Industrial Research, Brummeria, South Africa
| | - Anita Michel
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Gauteng 0110, South Africa
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Ndlandla FL, Ejoh V, Stoltz AC, Naicker B, Cromarty AD, van Wyngaardt S, Khati M, Rotherham LS, Lemmer Y, Niebuhr J, Baumeister CR, Al Dulayymi JR, Swai H, Baird MS, Verschoor JA. Standardization of natural mycolic acid antigen composition and production for use in biomarker antibody detection to diagnose active tuberculosis. J Immunol Methods 2016; 435:50-9. [PMID: 27247168 DOI: 10.1016/j.jim.2016.05.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/21/2016] [Accepted: 05/24/2016] [Indexed: 10/21/2022]
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis, is characterized by the abundance of species specific, antigenic cell wall lipids called mycolic acids. These wax-like molecules all share an identical, amphiphilic mycolic motif, but have different functional groups in a long hydrophobic hydrocarbon mero-chain that divide them into three main classes: alpha-, keto- and methoxy-mycolic acids. Whereas alpha-mycolic acids constitutively maintain an abundance of around 50%, the ratio of methoxy- to keto-mycolic acid types may vary depending on, among other things, the growth stage of M. tuberculosis. In human patients, antibodies to mycolic acids have shown potential as diagnostic serum biomarkers for active TB. Variations in mycolic acid composition affect the antigenic properties and can potentially compromise the precision of detection of anti-mycolic acids antibodies in patient sera to natural mixtures. We demonstrate this here with combinations of synthetic mycolic acid antigens, tested against TB patient and control sera. Combinations of methoxy- and α-mycolic acids are more antigenic than combinations of keto- and α-mycolic acids, showing the former to give a more sensitive test for TB biomarker antibodies. Natural mixtures of mycolic acids isolated from mature cultures of M. tuberculosis H37Rv give the same sensitivity as that with synthetic methoxy- and α-mycolic acids in combination, in a surface plasmon resonance inhibition biosensor test. To ensure that the antigenic activity of isolates of natural mycolic acids is reproducible, we cultured M. tuberculosis H37Rv on Middlebrook 7H10 solid agar plates to stationary growth phase in a standardized, optimal way. The proportions of mycolic acid classes in various batches of the isolates prepared from these cultures were compared to a commercially available natural mycolic acid isolate. LC-MS/MS and NMR data for quantitation of mycolic acids class compositions show that the variation in batches is small, suggesting that the quality of the results for anti-mycolic acid antibody detection in the TB patients should not be affected by different batches of natural mycolic acid antigens if prepared in a standard way.
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Affiliation(s)
- F L Ndlandla
- Polymers and Composites, Council for Scientific and Industrial Research, Pretoria, South Africa; Department of Biochemistry, University of Pretoria, South Africa
| | - V Ejoh
- Department of Biochemistry, University of Pretoria, South Africa
| | - A C Stoltz
- Division of Infectious Diseases, Faculty of Health Sciences, University of Pretoria, South Africa
| | - B Naicker
- Polymers and Composites, Council for Scientific and Industrial Research, Pretoria, South Africa; Department of Pharmacology, Faculty of Health Sciences, University of Pretoria, South Africa
| | - A D Cromarty
- Department of Pharmacology, Faculty of Health Sciences, University of Pretoria, South Africa
| | - S van Wyngaardt
- Department of Biochemistry, University of Pretoria, South Africa
| | - M Khati
- Biosciences, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - L S Rotherham
- Biosciences, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - Y Lemmer
- Polymers and Composites, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - J Niebuhr
- Department of Biochemistry, University of Pretoria, South Africa
| | - C R Baumeister
- Department of Biochemistry, University of Pretoria, South Africa
| | | | - H Swai
- Polymers and Composites, Council for Scientific and Industrial Research, Pretoria, South Africa
| | - M S Baird
- School of Chemistry, Bangor University, Wales, UK
| | - J A Verschoor
- Department of Biochemistry, University of Pretoria, South Africa
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Naicker B, Maharaj RC. HIV in acute care: a review of the burden of HIV-associated presentations to an Emergency Department. S Afr Fam Pract (2004) 2016. [DOI: 10.1080/20786190.2015.1079027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Labuschagne PW, Naicker B, Kalombo L. Micronization, characterization and in-vitro dissolution of shellac from PGSS supercritical CO 2 technique. Int J Pharm 2016; 499:205-216. [DOI: 10.1016/j.ijpharm.2015.12.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 12/02/2015] [Accepted: 12/09/2015] [Indexed: 10/22/2022]
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Naicker B, Maharaj RC. HIV in acute care: a review of the burden of HIV-associated presentations to an Emergency Department. S Afr Fam Pract (2004) 2016. [DOI: 10.4102/safp.v58i1.4286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Objective: To determine the burden of human immunodeficiency virus (HIV) disease and co-infection on a district-level Emergency Department (ED) in KwaZulu-Natal. Methods: A retrospective chart review was conducted of the case notes of adult medical patients who presented to the ED over a three-month period. Patients presenting with HIV disease and its complications were identified. Patient demographics, disease presentation and severity, investigations and procedures undertaken, and disposition of patients in the HIV-positive cohort were assessed.Results: 428 of the 861 (49.7%) medical patients presenting to the ED were HIV positive. Some 37% of patients did not know their HIV status. In the HIV-positive cohort, the median age of presentation was 37 years, with almost equal male-to-female distribution. Of the patients seen, 57.5% were referred and 68% of patients presented after hours. In total, 80% of patients were triaged as yellow code. The predominant systems involved were the respiratory and central nervous systems, with pulmonary tuberculosis, community-acquired pneumonia and meningitis being the most common diagnoses. X-rays and laboratory testing were the most common investigations requested. Lumbar punctures, pleural paracentesis and pericardiocentesis were common emergency procedures performed. The majority (89.3%) of patients were admitted to the medical ward. Of the HIV-positive patients, 33% were on anti-retroviral therapy. ED mortality was 1.9%.Conclusion: In South Africa, very little is known about the ED’s ability to cope with the HIV epidemic. This study highlights the significant impact HIV places on the resources of an ED. Strengthening of the primary health care system with a more aggressive approach to HIV testing and ARV initiation may contribute positively to reducing the burden of HIV emergencies and co-morbidities presenting to the ED.MeSH: Human Immunodeficiency virus (HIV); Emergency Department, South Africa, opportunistic infections; HIV testing
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Tukulula M, Hayeshi R, Fonteh P, Meyer D, Ndamase A, Madziva MT, Khumalo V, Labuschagne P, Lubuschagne P, Naicker B, Swai H, Dube A. Curdlan-Conjugated PLGA Nanoparticles Possess Macrophage Stimulant Activity and Drug Delivery Capabilities. Pharm Res 2015; 32:2713-26. [PMID: 25724161 DOI: 10.1007/s11095-015-1655-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 02/11/2015] [Indexed: 11/28/2022]
Abstract
PURPOSE There is significant interest in the application of nanoparticles to deliver immunostimulatory signals to cells. We hypothesized that curdlan (immune stimulating polymer) could be conjugated to PLGA and nanoparticles from this copolymer would possess immunostimulatory activity, be non-cytotoxic and function as an effective sustained drug release system. METHODS Carbodiimide chemistry was employed to conjugate curdlan to PLGA. The conjugate (C-PLGA) was characterized using (1)H and (13)C NMR, FTIR, DSC and TGA. Nanoparticles were synthesized using an emulsion-solvent evaporation technique. Immunostimulatory activity was characterized in THP-1 derived macrophages. MTT assay and real-time impedance measurements were used to characterize polymer and nanoparticle toxicity and uptake in macrophages. Drug delivery capability was assessed across Caco-2 cells using rifampicin as a model drug. RESULTS Spectral characterization confirmed successful synthesis of C-PLGA. C-PLGA nanoparticles enhanced phosphorylated ERK production in macrophages indicating cell stimulation. Nanoparticles provided slow release of rifampicin across Caco-2 cells. Polymers but not nanoparticles altered the adhesion profiles of the macrophages. Impedance measurements suggested Ca(2+) dependent uptake of nanoparticles by the macrophages. CONCLUSIONS PLGA nanoparticles with macrophage stimulating and sustained drug delivery capabilities have been prepared. These nanoparticles can be used to stimulate macrophages and concurrently deliver drug in infectious disease therapy.
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Affiliation(s)
- Matshawandile Tukulula
- Encapsulation and Delivery Group, Council for Scientific and Industrial Research, 1 Meiring Naude Road, Brummeria, Pretoria, 0001, South Africa
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Nkabinde LA, Shoba-Zikhali LNN, Semete-Makokotlela B, Kalombo L, Swai HS, Hayeshi R, Naicker B, Hillie TK, Hamman JH. Permeation of PLGA nanoparticles across different in vitro models. Curr Drug Deliv 2013; 9:617-27. [PMID: 22812395 DOI: 10.2174/156720112803529819] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2012] [Revised: 04/05/2012] [Accepted: 07/10/2012] [Indexed: 11/22/2022]
Abstract
Many drug delivery systems have indicated improvement in delivery of various drug molecules and among these biodegradable and biocompatible polymers such as poly(D,L-lactide-co-glycolide) (PLGA) have been shown to enhance intracellular uptake of drug candidates when formulated as nanoparticles. PLGA nanoparticles were prepared by means of a double emulsion solvent evaporation technique and evaluated in terms of size, encapsulation efficiency, surface charge, isoniazid release and in vitro transport. The nanoparticles have an average size of 237 nm and were previously shown to be distributed in several tissues after oral administration without triggering an immune response. This study focussed on the in vitro permeation of the PLGA nanoparticles across different membranes and showed that although Rhodamine 6G-labelled nanoparticles are efficiently delivered across the intestinal epithelium, its epithelial permeability changes when a drug such as isoniazid is encapsulated. Future studies should focus on ways to optimise PLGA nanoparticle delivery when a drug such as isoniazid is encapsulated for instance by coating with polymers such as polyethylene glycol.
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Affiliation(s)
- Lindiwe A Nkabinde
- Council for Scientific and Industrial Research, Biosciences, P.O Box 395, Pretoria, 0001, South Africa
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