Development and evaluation of sunscreen creams containing morin-encapsulated nanoparticles for enhanced UV radiation protection and antioxidant activity

The objective of present work was to develop novel sunscreen creams containing polymeric nanoparticles (NPs) of morin. Polymeric NPs containing morin were prepared and optimized. The creams containing morin NPs were also prepared and evaluated. Optimized NPs exhibited particle size of 90.6 nm and zeta potential of −31 mV. The entrapment efficiency of morin, within the polymeric NPs, was found to be low (12.27%). Fourier transformed infrared spectroscopy and differential scanning calorimetry studies revealed no interaction between morin and excipients. Transmission electron microscopy and atomic force microscopy revealed that the NPs were spherical in shape with approximately 100 nm diameter. Optimized NPs showed excellent in vitro free radical scavenging activity. Skin permeation and deposition of morin from its NPs was higher than its plain form. Different sunscreen creams (SC1–SC8) were formulated by incorporating morin NPs along with nano zinc oxide and nano titanium dioxide. SC5 and SC8 creams showed excellent sun protection factor values (≈40). In vitro and in vivo skin permeation studies of sunscreen creams containing morin NPs indicated excellent deposition of morin within the skin. Morin NPs and optimized cream formulations (SC5 and SC8) did not exhibit cytotoxicity in Vero and HaCaT cells. Optimized sunscreen creams showed excellent dermal safety. SC5 and SC8 creams demonstrated exceptional in vivo antioxidant effect (estimation of catalase, superoxide dismutase, and glutathione) in UV radiation-exposed rats. The optimized sunscreen creams confirmed outstanding UV radiation protection as well as antioxidant properties.

Development and validation of RP-HPLC method with ultraviolet detection for estimation of montelukast in rabbit plasma: Application to preclinical pharmacokinetics

OBJECTIVE

To develop a liquid-liquid extraction based reverse phase liquid chromatography method for estimation of montelukast in rabbit plasma.

METHODS

Chromatographic separation was carried out using Phenomenex Luna C18 column (250 mm × 4.6 mm × 5 μm) with mobile phase composed of ammonium acetate buffer (20 Mm), pH 5.5 and acetonitrile in 20:80, v/v ratio. The analyte was monitored with UV detector at 345 nm. The developed method was validated with respect to linearity, accuracy, precision, specificity and stability.

RESULTS

The peak area ratio of montelukast (MKS) to that of internal standard was used for the quantification of samples. Calibration curves were linear in the concentration range of 20-2000 ng mL(-1). The LOD and LLOQ of present method were found out to be 10 ng mL(-1) and 20 ng mL(-1) respectively. The intra-day and inter-day %CV values for MKS were below 6.06% and 8.43%. Intra-day and inter-day accuracies were within 95.81% and 110.90%, respectively. Extraction recoveries of drug from rabbit plasma were >66.47%.

CONCLUSION

A simple, alternative, reproducible and sensitive HPLC-UV method was developed for MKS that can be used in preclinical pharmacokinetics.

Osmotically controlled pulsatile release capsule of montelukast sodium for chronotherapy: statistical optimization, in vitro and in vivo evaluation

The purpose of present study was to design, optimize and evaluate osmotically controlled pulsatile release capsule (PRC) of montelukast sodium (MKS) for the prevention of episodic attack of asthma in early morning and associated allergic rhinitis. Assembly of the capsular systems consisted of push, active and plug tablet arranged from bottom to top in hard gelatin capsule. The capsule system was coated with a semi-permeable membrane of cellulose acetate and drilled towards plug side in cap. A three-factor, three-level central composite design (CCD) with α = 1 was introduced to execute the experiments and quadratic polynomial model was generated to predict and assess the independent variables with respect to the dependent variables. The composition of optimal formulation was determined as weight of push tablet 138 mg (coded value: +0.59), plug tablet 60 mg (coded value: +0.49) and coating weight gain of 8.4 mg (coded value: -0.82). The results showed that the optimal formulation of PRCs had lag time of 4.5 h, release at 6 and 12 h are 61.95% and 96.29%, respectively. The X-ray radiographic imaging study was carried out to monitor the in vivo behavior of developed barium sulfate-loaded PRCs in rabbits under fasting conditions. In vivo pharmacokinetic study revealed Tmax of 2 h for marketed tablets; however 7 h for PRCs with initial lag time of 4 h. Thus designed capsular system may be helpful for patients with episodic attack of asthma in early morning and associated allergic rhinitis.

Informed consent: Issues and challenges

Informed consent is an ethical and legal requirement for research involving human participants. It is the process where a participant is informed about all aspects of the trial, which are important for the participant to make a decision and after studying all aspects of the trial the participant voluntarily confirms his or her willingness to participate in a particular clinical trial and significance of the research for advancement of medical knowledge and social welfare. The concept of informed consent is embedded in the principles of Nuremberg Code, The Declaration of Helsinki and The Belmont Report. Informed consent is an inevitable requirement prior to every research involving human being as subjects for study. Obtaining consent involves informing the subject about his or her rights, the purpose of the study, procedures to be undertaken, potential risks and benefits of participation, expected duration of study, extent of confidentiality of personal identification and demographic data, so that the participation of subjects in the study is entirely voluntary. This article provides an overview of issues in informed consent: The obligations of investigator, sponsor and Institutional Review Board to protect rights and welfare of human research subjects. It discusses about the basic elements of informed consent and the process to be followed while obtaining informed consent. Some of the circumstances under which informed consent can be waived and ethical challenges faced by physicians in obtaining informed consent from subjects are also highlighted in this article.