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Advantageous characteristics of PVP - pa0902do - 2021-09-02
Advantageous characteristics of PVP
PVP-Polyvinylpyrrolidone is a nonionic water-soluble polymer and can be applied in a variety of fields-of-use owing to following advantageous characteristics.
1. Good solubility in water as well as various organic solvents
2. Good affinity to various polymers and resins
3. High hygroscopicity
4. Good film formation property
5. Good adhesiveness to various substrates
6. Good chelate / complex formation property
Polyvinylpyrrolidone (PVP) is a water-soluble polymer obtained by polymerization of monomer N-vinylpyrrolidone. PVP is an inert, non-toxic, temperature-resistant, pH-stable, biocompatible, biodegradable polymer that helps to encapsulate and cater both hydrophilic and lipophilic drugs. These advantages enable PVP versatile excipients in the formulation development of broad conventional to novel controlled delivery systems. PVP has tunable properties and can be used as a brace component for gene delivery, orthopedic implants, and tissue engineering applications. Based on different molecular weights and modified forms, PVP can lead to exceptional beneficial features with varying chemical properties. Graft copolymerization and other techniques assist PVP to conjugate with poorly soluble drugs that can inflate bioavailability and even introduces the desired swelling tract for their control or sustained release. The present review provides chemistry, mechanical, physicochemical properties, evaluation parameters, dewy preparation methods of PVP derivatives intended for designing conventional to controlled systems for drug, gene, and cosmetic delivery. The past and growing interest in PVP establishes it as a promising polymer to enhance the trait and performance of current generation pharmaceutical dosage forms. Furthermore, the scrutiny explores existing patents, marketed products, new and futuristic approaches of PVP that have been identified and scope for future development, characterization, and its use. The exploration spotlights the importance and role of PVP in the design of Povidone-iodine (PVP–I) and clinical trials to assess therapeutic efficacy against the COVID-19 in the current pandemic scenario.
PVPP is a synthetic, high-molecular-weight clarifying agent made up of cross-linked monomer of polyvinylpyrrolidone. PVPP has long been used in the beverage industry as a polyphenol adsorbent. Although, it has been called as a “protein-like” fining agent, insoluble PVPP interacts with only few reactive groups. Hence, PVPP is used for binding and removing smaller phenolic compounds such as catechins and anthocyanins, which are responsible for causing browning and bitterness in wines. However, PVPP, along with charcoal and casein, can remove resveratrol, a component that imparts certain health benefits.
Polyvinylpyrrolidone (PVP) is a linear polymer of 1-vinyl-2-pyrrolidone monomers used as a binder, emulsion stabilizer, film former, hair fixative, and suspending agent-nonsurfactant. The molecular weight of the polymer ranges from 10,000 to 700,000. PVP K-30, with an average molecular weight of 40,000, is typically used in cosmetic formulations. The highest concentration reported to be used is 35%. There was no significant absorption of PVP K-30 given orally to rats, and the acute oral LD50 was >100 g/kg for rats and guinea pigs. Neither toxic effects nor gross lesions were found in rats maintained for two years on a diet containing 10% PVP K-30. Short-term PVP inhalation studies produced mild lymphoid hyperplasia and fibroplasia in rats, but no inflammatory response. In animal studies, no evidence of significant ocular irritation, skin irritation, or skin sensitization was found at PVP-iodine solution concentrations of 10%. While PVP-iodine is not a cosmetic ingredient, these negative findings were considered to support the safety of the PVP component. Undiluted PVP K-30 was not a dermal irritant or sensitizer in clinical tests. No developmental toxicity was seen in vehicle controls where PVP was used as a vehicle for another agent. In certain assay systems, PVP was genotoxic, but was negative in the majority of studies. Orally administered PVP significantly decreased the rate of bladder tumors in mice exposed to bracken fern. Several studies tested the carcinogenicity of subcutaneous implants of particulate PVP in rats, mice, and rabbits. Although the majority of these studies conducted in rats were positive, tumors (sarcomas) were localized to the site of implantation. Based on the available data, it was concluded that PVP is safe as used in cosmetics.
Polyvinylpyrrolidone (PVP) is a linear polymer of 1-vinyl-2-pyrrolidone monomers used as a binder, emulsion stabilization of suspensions, film former, hair fixative, and suspending agent-nonsurfactant. The molecular weight of the polymer ranges from 10,000 to 700,000. PVP K-30, with an average molecular weight of 40,000, is typically used in cosmetic formulations. The highest concentration reported to be used is 35%. There was no significant absorption of PVP K-30 given orally to rats, and the acute oral LD50 was >100 g/kg for rats and guinea pigs. Neither toxic effects nor gross lesions were found in rats maintained for two years on a diet containing 10% PVP K-30. Short-term PVP inhalation studies produced mild lymphoid hyperplasia and fibroplasia in rats, but no inflammatory response. In animal studies, no evidence of significant ocular irritation, skin irritation, or skin sensitization was found at PVP-iodine solution concentrations of 10%. While PVP-iodine is not a cosmetic ingredient, these negative findings were considered to support the safety of the PVP component. Undiluted PVP K-30 was not a dermal irritant or sensitizer in clinical tests. No developmental toxicity was seen in vehicle controls where PVP was used as a vehicle for another agent. In certain assay systems, PVP was genotoxic, but was negative in the majority of studies. Orally administered PVP significantly decreased the rate of bladder tumors in mice exposed to bracken fern. Several studies tested the carcinogenicity of subcutaneous implants of particulate PVP in rats, mice, and rabbits. Although the majority of these studies conducted in rats were positive, tumors (sarcomas) were localized to the site of implantation. Based on the available data, it was concluded that PVP is safe as used in cosmetics.