The aim of present study was to formulate and evaluate nanoparticles of carvedilol by using different hydrophilic polymers. Carvedilol was selected as a suitable drug for gastro- retentive nanoparticles due to its short half life, low bioavailability, high frequency of administration, and narrow absorption window in stomach and upper part of GIT. The nano-precipitation method was used to prepare nanoparticles so as to avoid both chlorinated solvents and surfactants to prevent their toxic effect on the body. Nanoparticles of  carvedilol were prepared by using hydrophilic polymers such as HPMC K100M, chitosan, and gelatin. The prepared formulations were then characterized for particle size, polydispersity index, zeta potential, loading efficiency, encapsulation efficiency and drug-excipient compatibility. The prepared nanoparticulate formulations of carvedilol  with different polymers in 1:1 ratio have shown particle size in the range of 250.12-743.07 nm, polydispersity index (PDI) in the range of 0.681-1.0, zeta potential in the range of -14.2 to +33.2 mV, loading efficiency in the range of 8.74-17.54%, and entrapment efficiency in the range of 55.7%-74.2%. Nanoparticulate formulation prepared with chitosan in 1:1 ratio showed satisfactory results i.e. average particle size 312.04 nm, polydispersity index 0.681, zeta potential 33.2 mV, loading efficiency 17.54%, and entrapment efficiency 73.4%. FTIR study concluded that no major interaction occurred between  the drug and polymers used in the present study. Keywords: Nanoparticles; gastro-retentive; nano-precipitation, polydispersity index, zeta potential; entrapment efficiency.

Labetalol is an adrenergic receptor blocking agent used in the treatment of hypertension and characterized by high solubility and high permeability which corresponds to BCS class I drug. Plasma half life ranges from 6 & bioavailability is 25%. Ethyl cellulose was used as a rate controlling polymer. Effects of addition of ethyl cellulose on in vitro dissolution were studied. Nanoparticles were formulated using different polymer ratios. In vitro drug release was carried out by using USP Type II at 50 rpm in 900 ml of acidic dissolution medium (pH 1.2) for 2 hours, followed by 900 ml alkaline dissolution medium (pH7.4) for 12 hours. Mean dissolution time is used to characterize drug release rate from a dosage form. Several kinetic models were applied to the dissolution profiles to determine the drug release kinetics. Excipients are selected by FTIR studies. Finally the nanoparticles were evaluated for various characteristics like encapsulation efficiency, percentage yield, partial size and the In vitro release for 12 hrs.  The nanoparticles were found to be discrete, spherical, and free-flowing.  The nanoparticles were uniform in size, and the microencapsulation efficiency was in the range of 52.5-81.7%. The surface morphology of prepared Labetalol nanoparticles was observed under scanning electron Microscopy. Nanoparticles had good spherical geometry. The stability study was performed at 40ºC ± 2ºC and 75 ± 5% RH for 6 months. Keywords: Nanoparticles; Labetalol, Hypertension, Ethyl Cellulose, Dissolution, entrapment efficiency.

Formulated Metoprolol sustained release microspheres. Microspheres are prepared by Ionic-Gelation method using Hydroxy Propyl Methyl Cellulose (HPMC), Ethyl cellulose and Sodium CMC for sustained release in view to prolong drug release. Metoprolol is an adreno receptor beta blocking agent used in the treatment of hypertension and characterized by high solubility and high permeability which corresponds to BCS class I drug. Plasma half life ranges from 3 to 7 hours & oral bioavailability is 50% hence require frequent oral administration for adequate treatment of hypertension. Administration of conventional tablet of Metoprolol has been reported to exhibit fluctuations in plasma drug levels resulting in either manifestation side effects reduction in drug concentration at receptor site. so that oral sustained dosage form was developed. The microspheres were evaluated for various characteristics like encapsulation efficiency, percentage yield, partial size and the In vitro release for 12 hours. The Microspheres were found to be discrete, spherical, and free-flowing. The microspheres were uniform in size, and the microencapsulation efficiency was in the range of 91.7%. Microspheres had good spherical geometry.

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