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Environment-responsive drug delivery systems have emerged as attractive alternative to traditional systems, delivering therapeutic agents on-demand to their target tissue. Temperature and pH arise as two of the most commonly utilized stimuli for triggering these responses. Among polymeric carriers, temperature and pH dual-responsive nanocarriers were developed to exhibit changes in drug release rate or particle size upon change in environment’s pH and temperature. In this chapter, various design aspects of temperature- and pH -dual-responsive polymeric nanocarriers are discussed in details with examples, illustrating different responsive polymeric materials used in their fabrication. The interplay between temperature- and pH-responsiveness within the polymeric nanocarriers are discussed too.

Environment-responsive drug delivery systems have emerged as attractive alternative to traditional systems, delivering therapeutic agents on-demand to their target tissue. Temperature and pH arise as two of the most commonly utilized stimuli for triggering these responses. Among polymeric carriers, temperature and pH dual-responsive nanocarriers were developed to exhibit changes in drug release rate or particle size upon change in environment’s pH and temperature. In this chapter, various design aspects of temperature- and pH -dual-responsive polymeric nanocarriers are discussed in details with examples, illustrating different responsive polymeric materials used in their fabrication. The interplay between temperature- and pH-responsiveness within the polymeric nanocarriers are discussed too.

Environment-responsive drug delivery systems have emerged as attractive alternative to traditional systems, delivering therapeutic agents on-demand to their target tissue. Temperature and pH arise as two of the most commonly utilized stimuli for triggering these responses. Among polymeric carriers, temperature and pH dual-responsive nanocarriers were developed to exhibit changes in drug release rate or particle size upon change in environment’s pH and temperature. In this chapter, various design aspects of temperature- and pH -dual-responsive polymeric nanocarriers are discussed in details with examples, illustrating different responsive polymeric materials used in their fabrication. The interplay between temperature- and pH-responsiveness within the polymeric nanocarriers are discussed too.

Self-assembled particles, based on non-covalent interactions, are attractive drug carriers with a relatively simple structure and easy preparation. Tannic acid (TA) is an anionic polyphenolic compound with a wide range of molecular interactions and diverse applications in drug delivery research. Here, we propose the use of TA complexes with cationic antibiotics as a new pH-responsive drug carrier of high drug loading and optimal stability. TA complexes were prepared with three water-soluble antibiotics; colistin sulfate (COL), gentamicin sulfate (GEN) and gatifloxacin (GAT). Complexes’ size ranged from several-hundred nanometers to few microns. For selected particles, drug loading ranged from 30 to 36%. Importantly, we demonstrate the impact of drug-carrier interactions, studied via infrared spectroscopy and molecular modeling, on final complex stability and performance; the complexes resisted dissociation in presence of serum at physiological pH to variable degrees and showed different drug release profiles. However, all complexes dissociated upon medium acidification, releasing their drug payload and demonstrating expected antibacterial effect. These results demonstrate that TA/antibiotic self-assembled complexes represent an excellent carrier for pH-sensitive delivery of water-soluble drugs. In addition to system’s simplicity and low cost, complexes were easily prepared with high drug loading and desirable pH-dependent association/dissociation profile.

Self-assembled particles, based on non-covalent interactions, are attractive drug carriers with a relatively simple structure and easy preparation. Tannic acid (TA) is an anionic polyphenolic compound with a wide range of molecular interactions and diverse applications in drug delivery research. Here, we propose the use of TA complexes with cationic antibiotics as a new pH-responsive drug carrier of high drug loading and optimal stability. TA complexes were prepared with three water-soluble antibiotics; colistin sulfate (COL), gentamicin sulfate (GEN) and gatifloxacin (GAT). Complexes’ size ranged from several-hundred nanometers to few microns. For selected particles, drug loading ranged from 30 to 36%. Importantly, we demonstrate the impact of drug-carrier interactions, studied via infrared spectroscopy and molecular modeling, on final complex stability and performance; the complexes resisted dissociation in presence of serum at physiological pH to variable degrees and showed different drug release profiles. However, all complexes dissociated upon medium acidification, releasing their drug payload and demonstrating expected antibacterial effect. These results demonstrate that TA/antibiotic self-assembled complexes represent an excellent carrier for pH-sensitive delivery of water-soluble drugs. In addition to system’s simplicity and low cost, complexes were easily prepared with high drug loading and desirable pH-dependent association/dissociation profile.

Self-assembled particles, based on non-covalent interactions, are attractive drug carriers with a relatively simple structure and easy preparation. Tannic acid (TA) is an anionic polyphenolic compound with a wide range of molecular interactions and diverse applications in drug delivery research. Here, we propose the use of TA complexes with cationic antibiotics as a new pH-responsive drug carrier of high drug loading and optimal stability. TA complexes were prepared with three water-soluble antibiotics; colistin sulfate (COL), gentamicin sulfate (GEN) and gatifloxacin (GAT). Complexes’ size ranged from several-hundred nanometers to few microns. For selected particles, drug loading ranged from 30 to 36%. Importantly, we demonstrate the impact of drug-carrier interactions, studied via infrared spectroscopy and molecular modeling, on final complex stability and performance; the complexes resisted dissociation in presence of serum at physiological pH to variable degrees and showed different drug release profiles. However, all complexes dissociated upon medium acidification, releasing their drug payload and demonstrating expected antibacterial effect. These results demonstrate that TA/antibiotic self-assembled complexes represent an excellent carrier for pH-sensitive delivery of water-soluble drugs. In addition to system’s simplicity and low cost, complexes were easily prepared with high drug loading and desirable pH-dependent association/dissociation profile.