Akash Gupta - Academia.edu (original) (raw)

Papers by Akash Gupta

ACS Applied Materials & Interfaces, 2016

Gold nanoparticles provide an excellent platform for biological and material applications due to ... more Gold nanoparticles provide an excellent platform for biological and material applications due to their unique physical and chemical properties. However, decreased colloidal stability and formation of irreversible aggregates while freeze-drying nanomaterials limit their use in real world applications. Here, we report a new generation of surface ligands based on a combination of short oligo (ethylene glycol) chains and zwitterions capable of providing nonfouling characteristics while maintaining colloidal stability and functionalization capabilities. Additionally, conjugation of these gold nanoparticles with avidin can help the development of a universal toolkit for further functionalization of nanomaterials.

ACS Infectious Diseases, 2015

Treatment of biofilm-associated infections is challenging, requiring the development of new thera... more Treatment of biofilm-associated infections is challenging, requiring the development of new therapeutic strategies. In this viewpoint, we discuss the use of nanoparticle-based systems as active therapeutic agents and as vehicles to transport drugs to the site of infection. These applications require understanding of the surface interactions of nanoparticles with bacteria/biofilms, an aspect that we likewise summarize.

ACS nano, Jan 17, 2015

Bacterial biofilms are widely associated with persistent infections. High resistance to conventio... more Bacterial biofilms are widely associated with persistent infections. High resistance to conventional antibiotics and prevalent virulence makes eliminating these bacterial communities challenging therapeutic targets. We describe here the fabrication of a nanoparticle-stabilized capsule with a multicomponent core for the treatment of biofilms. The peppermint oil and cinnamaldehyde combination that comprises the core of the capsules act as potent antimicrobial agents. An in situ reaction at the oil/water interface between the nanoparticles and cinnamaldehyde structurally augments the capsules to efficiently deliver the essential oil payloads, effectively eradicating biofilms of clinically isolated pathogenic bacteria strains. In contrast to their antimicrobial action, the capsules selectively promoted fibroblast proliferation in a mixed bacteria/mammalian cell system making them promising for wound healing applications.

Chemical Society reviews, Jan 8, 2015

Metallic nanoparticles provide versatile scaffolds for biosensing applications. In this review, w... more Metallic nanoparticles provide versatile scaffolds for biosensing applications. In this review, we focus on the use of metallic nanoparticles for cell surface sensings. Examples of the use of both specific recognition and array-based "chemical nose" approaches to cell surface sensing will be discussed.

Macromolecular Rapid Communications, 2015

nanofi ber surfaces, including plasma treatment, coelectrospinning, chemical modifi cation, and s... more nanofi ber surfaces, including plasma treatment, coelectrospinning, chemical modifi cation, and surface graft polymerization. However, these methods have limitations in terms of functional group density, where the plasma treatment cannot effectively modify the surface of buried nanofi bers and grafting polymer on the nanofi ber surface typically generates a low density of functional groups. Integration of nanoparticles (NPs) into nanofi bers provides a promising approach to generate dense functionalization of nanofi bers with desired properties. Through the appropriate choice of NP core, NPs can incorporate their unique physicochemical properties to nanofi bers such as magnetic and fl uorescent properties. NPnanofi ber composites feature enhanced functionality and improved performance for nanofi ber alignment, solar cells, and photocatalytic applications. NPs can be introduced to the nanofi ber structures through direct synthesis and assembly of NPs, covalent conjugation, and supramolecular interactions (e.g., hydrogen-bonding and electrostatic interactions). A facile method is developed to functionalize nanofi ber surfaces with nanoparticles (NPs) through dithiocarbamate chemistry. Gold nanoparticles (AuNPs) and quantum dots (QDs) are immobilized on the nanofi ber surface. These surfaces provide scaffolds for further supramolecular functionalization, as demonstrated through the Förster resonance energy transfer (FRET) pairing of QD-decorated fi bers and fl uorescent proteins.

ACS nano, 2014

We present the use of functionalized gold nanoparticles (AuNPs) to combat multi-drug-resistant pa... more We present the use of functionalized gold nanoparticles (AuNPs) to combat multi-drug-resistant pathogenic bacteria. Tuning of the functional groups on the nanoparticle surface provided gold nanoparticles that were effective against both Gram-negative and Gram-positive uropathogens, including multi-drug-resistant pathogens. These AuNPs exhibited low toxicity to mammalian cells, and bacterial resistance was not observed after 20 generations. A strong structure-activity relationship was observed as a function of AuNP functionality, providing guidance to activity prediction and rational design of effective antimicrobial nanoparticles.

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Bacterial infections cause 300 million cases of severe illness each year worldwide. Rapidly accel... more Bacterial infections cause 300 million cases of severe illness each year worldwide. Rapidly accelerating drug resistance further exacerbates this threat to human health. While dispersed (planktonic) bacteria represent a therapeutic challenge, bacterial biofilms present major hurdles for both diagnosis and treatment. Nanoparticles have emerged recently as tools for fighting drug-resistant planktonic bacteria and biofilms. In this review, we present the use of nanoparticles as active antimicrobial agents and drug delivery vehicles for antibacterial therapeutics. We further focus on how surface functionality of nanomaterials can be used to target both planktonic bacteria and biofilms. PubMed Abstract | Free Full Text 2. Costerton JW, Cheng KJ, Geesey GG, et al.: Bacterial biofilms in nature and disease. Annu Rev Microbiol. 1987; 41: 435-64. PubMed Abstract | Publisher Full Text 3. Costerton JW, Stewart PS, Greenberg EP: Bacterial biofilms: a common cause of persistent infections. Science. 1999; 284(5418): 1318-22. PubMed Abstract | Publisher Full Text 4. Spellberg B, Powers JH, Brass EP, et al.: Trends in antimicrobial drug development: implications for the future. Clin Infect Dis. 2004; 38(9): 1279-86. PubMed Abstract | Publisher Full Text 5. De M, Ghosh PS, Rotello VM: Applications of Nanoparticles in Biology. Adv Mater. 2008; 20(22): 4225-41. Publisher Full Text 6. Davis ME, Chen ZG, Shin DM: Nanoparticle therapeutics: an emerging treatment modality for cancer. Nat Rev Drug Discov. 2008; 7(9): 771-82. PubMed Abstract | Publisher Full Text 7. Jiang Z, Le ND, Gupta A, et al.: Cell surface-based sensing with metallic nanoparticles. Chem Soc Rev. 2015; 44(13): 4264-74. PubMed Abstract | Publisher Full Text | Free Full Text 8. Daniel MC, Astruc D: Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. Chem Rev. 2004; 104(1): 293-346. PubMed Abstract | Publisher Full Text 9. Falagas ME, Kasiakou SK: Colistin: the revival of polymyxins for the management of multidrug-resistant gram-negative bacterial infections. Clin Infect Dis. 2005; 40(9): 1333-41. PubMed Abstract | Publisher Full Text 10. Cui L, Iwamoto A, Lian JQ, et al.: Novel mechanism of antibiotic resistance originating in vancomycin-intermediate Staphylococcus aureus. Antimicrob Agents Chemother. 2006; 50(2): 428-38. PubMed Abstract | Publisher Full Text | Free Full Text 11. Li XZ, Nikaido H: Efflux-mediated drug resistance in bacteria. Drugs. 2004; 64(2): 159-204. PubMed Abstract | Publisher Full Text 12. Livermore DM: beta-Lactamases in laboratory and clinical resistance. Clin Microbiol Rev. 1995; 8(4): 557-84. PubMed Abstract | Free Full Text 13. Davies J, Wright GD: Bacterial resistance to aminoglycoside antibiotics. Trends Microbiol. 1997; 5(6): 234-40. PubMed Abstract | Publisher Full Text 14. Courvalin P: Vancomycin resistance in gram-positive cocci. Clin Infect Dis. 2006; 42(Suppl 1): S25-34. PubMed Abstract | Publisher Full Text 15. Hajipour MJ, Fromm KM, Ashkarran AA, et al.: Antibacterial properties of nanoparticles. Trends Biotechnol. 2012; 30(10): 499-511. PubMed Abstract | Publisher Full Text 16. Miller KP, Wang L, Benicewicz BC, et al.: Inorganic nanoparticles engineered to attack bacteria. Chem Soc Rev. 2015; 44(21): 7787-807.

ACS Applied Materials & Interfaces, 2016

Gold nanoparticles provide an excellent platform for biological and material applications due to ... more Gold nanoparticles provide an excellent platform for biological and material applications due to their unique physical and chemical properties. However, decreased colloidal stability and formation of irreversible aggregates while freeze-drying nanomaterials limit their use in real world applications. Here, we report a new generation of surface ligands based on a combination of short oligo (ethylene glycol) chains and zwitterions capable of providing nonfouling characteristics while maintaining colloidal stability and functionalization capabilities. Additionally, conjugation of these gold nanoparticles with avidin can help the development of a universal toolkit for further functionalization of nanomaterials.

ACS Infectious Diseases, 2015

Treatment of biofilm-associated infections is challenging, requiring the development of new thera... more Treatment of biofilm-associated infections is challenging, requiring the development of new therapeutic strategies. In this viewpoint, we discuss the use of nanoparticle-based systems as active therapeutic agents and as vehicles to transport drugs to the site of infection. These applications require understanding of the surface interactions of nanoparticles with bacteria/biofilms, an aspect that we likewise summarize.

ACS nano, Jan 17, 2015

Bacterial biofilms are widely associated with persistent infections. High resistance to conventio... more Bacterial biofilms are widely associated with persistent infections. High resistance to conventional antibiotics and prevalent virulence makes eliminating these bacterial communities challenging therapeutic targets. We describe here the fabrication of a nanoparticle-stabilized capsule with a multicomponent core for the treatment of biofilms. The peppermint oil and cinnamaldehyde combination that comprises the core of the capsules act as potent antimicrobial agents. An in situ reaction at the oil/water interface between the nanoparticles and cinnamaldehyde structurally augments the capsules to efficiently deliver the essential oil payloads, effectively eradicating biofilms of clinically isolated pathogenic bacteria strains. In contrast to their antimicrobial action, the capsules selectively promoted fibroblast proliferation in a mixed bacteria/mammalian cell system making them promising for wound healing applications.

Chemical Society reviews, Jan 8, 2015

Metallic nanoparticles provide versatile scaffolds for biosensing applications. In this review, w... more Metallic nanoparticles provide versatile scaffolds for biosensing applications. In this review, we focus on the use of metallic nanoparticles for cell surface sensings. Examples of the use of both specific recognition and array-based "chemical nose" approaches to cell surface sensing will be discussed.

Macromolecular Rapid Communications, 2015

nanofi ber surfaces, including plasma treatment, coelectrospinning, chemical modifi cation, and s... more nanofi ber surfaces, including plasma treatment, coelectrospinning, chemical modifi cation, and surface graft polymerization. However, these methods have limitations in terms of functional group density, where the plasma treatment cannot effectively modify the surface of buried nanofi bers and grafting polymer on the nanofi ber surface typically generates a low density of functional groups. Integration of nanoparticles (NPs) into nanofi bers provides a promising approach to generate dense functionalization of nanofi bers with desired properties. Through the appropriate choice of NP core, NPs can incorporate their unique physicochemical properties to nanofi bers such as magnetic and fl uorescent properties. NPnanofi ber composites feature enhanced functionality and improved performance for nanofi ber alignment, solar cells, and photocatalytic applications. NPs can be introduced to the nanofi ber structures through direct synthesis and assembly of NPs, covalent conjugation, and supramolecular interactions (e.g., hydrogen-bonding and electrostatic interactions). A facile method is developed to functionalize nanofi ber surfaces with nanoparticles (NPs) through dithiocarbamate chemistry. Gold nanoparticles (AuNPs) and quantum dots (QDs) are immobilized on the nanofi ber surface. These surfaces provide scaffolds for further supramolecular functionalization, as demonstrated through the Förster resonance energy transfer (FRET) pairing of QD-decorated fi bers and fl uorescent proteins.

ACS nano, 2014

We present the use of functionalized gold nanoparticles (AuNPs) to combat multi-drug-resistant pa... more We present the use of functionalized gold nanoparticles (AuNPs) to combat multi-drug-resistant pathogenic bacteria. Tuning of the functional groups on the nanoparticle surface provided gold nanoparticles that were effective against both Gram-negative and Gram-positive uropathogens, including multi-drug-resistant pathogens. These AuNPs exhibited low toxicity to mammalian cells, and bacterial resistance was not observed after 20 generations. A strong structure-activity relationship was observed as a function of AuNP functionality, providing guidance to activity prediction and rational design of effective antimicrobial nanoparticles.

[

Bacterial infections cause 300 million cases of severe illness each year worldwide. Rapidly accel... more Bacterial infections cause 300 million cases of severe illness each year worldwide. Rapidly accelerating drug resistance further exacerbates this threat to human health. While dispersed (planktonic) bacteria represent a therapeutic challenge, bacterial biofilms present major hurdles for both diagnosis and treatment. Nanoparticles have emerged recently as tools for fighting drug-resistant planktonic bacteria and biofilms. In this review, we present the use of nanoparticles as active antimicrobial agents and drug delivery vehicles for antibacterial therapeutics. We further focus on how surface functionality of nanomaterials can be used to target both planktonic bacteria and biofilms. PubMed Abstract | Free Full Text 2. Costerton JW, Cheng KJ, Geesey GG, et al.: Bacterial biofilms in nature and disease. Annu Rev Microbiol. 1987; 41: 435-64. PubMed Abstract | Publisher Full Text 3. Costerton JW, Stewart PS, Greenberg EP: Bacterial biofilms: a common cause of persistent infections. Science. 1999; 284(5418): 1318-22. PubMed Abstract | Publisher Full Text 4. Spellberg B, Powers JH, Brass EP, et al.: Trends in antimicrobial drug development: implications for the future. Clin Infect Dis. 2004; 38(9): 1279-86. PubMed Abstract | Publisher Full Text 5. De M, Ghosh PS, Rotello VM: Applications of Nanoparticles in Biology. Adv Mater. 2008; 20(22): 4225-41. Publisher Full Text 6. Davis ME, Chen ZG, Shin DM: Nanoparticle therapeutics: an emerging treatment modality for cancer. Nat Rev Drug Discov. 2008; 7(9): 771-82. PubMed Abstract | Publisher Full Text 7. Jiang Z, Le ND, Gupta A, et al.: Cell surface-based sensing with metallic nanoparticles. Chem Soc Rev. 2015; 44(13): 4264-74. PubMed Abstract | Publisher Full Text | Free Full Text 8. Daniel MC, Astruc D: Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology. Chem Rev. 2004; 104(1): 293-346. PubMed Abstract | Publisher Full Text 9. Falagas ME, Kasiakou SK: Colistin: the revival of polymyxins for the management of multidrug-resistant gram-negative bacterial infections. Clin Infect Dis. 2005; 40(9): 1333-41. PubMed Abstract | Publisher Full Text 10. Cui L, Iwamoto A, Lian JQ, et al.: Novel mechanism of antibiotic resistance originating in vancomycin-intermediate Staphylococcus aureus. Antimicrob Agents Chemother. 2006; 50(2): 428-38. PubMed Abstract | Publisher Full Text | Free Full Text 11. Li XZ, Nikaido H: Efflux-mediated drug resistance in bacteria. Drugs. 2004; 64(2): 159-204. PubMed Abstract | Publisher Full Text 12. Livermore DM: beta-Lactamases in laboratory and clinical resistance. Clin Microbiol Rev. 1995; 8(4): 557-84. PubMed Abstract | Free Full Text 13. Davies J, Wright GD: Bacterial resistance to aminoglycoside antibiotics. Trends Microbiol. 1997; 5(6): 234-40. PubMed Abstract | Publisher Full Text 14. Courvalin P: Vancomycin resistance in gram-positive cocci. Clin Infect Dis. 2006; 42(Suppl 1): S25-34. PubMed Abstract | Publisher Full Text 15. Hajipour MJ, Fromm KM, Ashkarran AA, et al.: Antibacterial properties of nanoparticles. Trends Biotechnol. 2012; 30(10): 499-511. PubMed Abstract | Publisher Full Text 16. Miller KP, Wang L, Benicewicz BC, et al.: Inorganic nanoparticles engineered to attack bacteria. Chem Soc Rev. 2015; 44(21): 7787-807.