Research Journal of Pharmaceutical Dosage Form and Technology

Aachal Kolhe ¹, Akshda Chauhan ¹, Aishwarya Dongre ¹

Affiliations
1 P.R. Pote Patil College of Pharmacy, Amravati, Kathora Road, Amravati-444604., IN

Abstract

Cross-Linking the carbon atoms suffices to transform such material intoa superior material that may be resistant to temperature, pressure, corrosion, and that can be used in a variety of applications. Cross Linking is a stabilization process in polymer chemistry which leads to multidimensional extension of polymeric chain resulting in network structure. Cross-link is a bond which links one polymer chain to other. It can be ionic or covalent. Cross Linking changes a liquid polymer into ‘solid’ or ‘gel’ by restricting the ability of movement. When polymer chains are linked together by cross-links, they lose some of their ability to move as individual polymer chains. A liquid polymer (where the chains are freely flowing) can be turned into a ‘solid’ or ‘gel’ by cross-Linking the chains together. Cross Linking increases the molecular mass of a polymer. Cross-linked polymers are important because they are mechanically strong and resistant to heat, wear and attack by solvents. Cross-link property has been used to improve the insolubility, mechanical strength, stiffness, and rigidity of polymer microbeads having potential applications in solid-phase synthesis, solid-phase extraction, and biomedical fields. Hydrogels represents a class of high-water content polymers with physical or chemical crosslinks. Their physical properties are similar to soft tissues. A popular approach to attaining controlled drugdelivery from polymer-based systemsinvolves the use of cross-linkers. In order to improve the properties of polymers specific toothier applications, they can be modified by either physical cross-linkers (high pressure, irradiation) or chemical cross-linkers (glutraldehyde,genipin).Therefore, synthesis of polymer with desired cross-linker (hydrophilic/hydrophobic/rigid/flexible) and concentration of cross-linker (cross-link density) is an important.Polyethylene (PE) once cross linked is advantageously employed in the fabrication of blanket insulation for electrical and telephone wires, pipes for the transport of cold and hot liquids, prostheses for the human body. In the present review, chemical cross-Linking by free-radical, condensation, UV radiation, and small-molecule cross-Linking are discussed in details.

Keywords

Cross Linking, Polymer, Hydro gel, liquid, bond, solid, polyethylene, free-radical.

Full Text

     

Aachal Kolhe ¹, Akshda Chauhan ¹, Aishwarya Dongre ¹

Affiliations
1 P.R. Pote Patil College of Pharmacy, Amravati, Kathora Road, Amravati-444604., IN

Abstract

Verapamil hydrochloride (VH) is a calcium channel blocking agent used in the treatment of hypertension, cardiac arrhythmia and angina pectoris. The short half life and high frequency of administration of VH makes it a suitable candidate for designing sustained drug delivery system. The aim of the present investigation was to develop a sustained release matrix tablet of verapamil hydrochloride (VH) using sodium alginate and cross linked sodium alginate and to evaluate the drug release kinetics. In order to achieve the required sustained release profile, the tablets were prepared by a wet granulation method. The formulated tablets were characterized for pre-compression and post-compression parameters and they were in the acceptable limits. The drug release data obtained after an in vitro dissolution study was fitted to various release kinetic models in order to evaluate the release mechanism and kinetics. The criterion for selecting the best fit model was linearity (coefficient of correlation). Drug release mechanism was found to follow a complex mixture of diffusion, swelling and erosion. The dosage form holds the potential to control the release rate of drug and extend the duration of action of a drug.

Keywords

Verapamil HCL, Matrix Tablet, Cross Linking, Sodium Alginate, Drug Release.

Full Text

     

Aachal Kolhe ¹, Akshda Chauhan ¹, Aishwarya Dongre ¹

Affiliations
1 P.R. Pote Patil College of Pharmacy, Amravati, Kathora Road, Amravati-444604., IN

Abstract

Cross-Linking the carbon atoms suffices to transform such material intoa superior material that may be resistant to temperature, pressure, corrosion, and that can be used in a variety of applications. Cross Linking is a stabilization process in polymer chemistry which leads to multidimensional extension of polymeric chain resulting in network structure. Cross-link is a bond which links one polymer chain to other. It can be ionic or covalent. Cross Linking changes a liquid polymer into ‘solid’ or ‘gel’ by restricting the ability of movement. When polymer chains are linked together by cross-links, they lose some of their ability to move as individual polymer chains. A liquid polymer (where the chains are freely flowing) can be turned into a ‘solid’ or ‘gel’ by cross-Linking the chains together. Cross Linking increases the molecular mass of a polymer. Cross-linked polymers are important because they are mechanically strong and resistant to heat, wear and attack by solvents. Cross-link property has been used to improve the insolubility, mechanical strength, stiffness, and rigidity of polymer microbeads having potential applications in solid-phase synthesis, solid-phase extraction, and biomedical fields. Hydrogels represents a class of high-water content polymers with physical or chemical crosslinks. Their physical properties are similar to soft tissues. A popular approach to attaining controlled drugdelivery from polymer-based systemsinvolves the use of cross-linkers. In order to improve the properties of polymers specific toothier applications, they can be modified by either physical cross-linkers (high pressure, irradiation) or chemical cross-linkers (glutraldehyde, genipin).Therefore, synthesis of polymer with desired cross-linker (hydrophilic/hydrophobic/rigid/flexible) and concentration of cross-linker (cross-link density) is an important.Polyethylene (PE) once cross linked is advantageously employed in the fabrication of blanket insulation for electrical and telephone wires, pipes for the transport of cold and hot liquids, prostheses for the human body. In the present review, chemical cross-Linking by free-radical, condensation, UV radiation, and small-molecule cross-Linking are discussed in details.

Keywords

Cross Linking, Polymer, Hydro gel, liquid, bond, solid, polyethylene, free-radical.

Full Text