1.
Formulation, Characterization And In Vitro Studies Of Indapamide Sustained Release Matrix Tablet From Natural Polymer Muhammad Irfan Masood
by Beenish Shams (2012-VA-643) | Shaista Qamar | Dr. Mateen Abbas .
Material type: ; Literary form:
not fiction
Publisher: 2014Dissertation note: With each advancement in medicine, we are faced with the need for an effective method of drug delivery which is easy for the patient and maintains the bioavailability of the drug. Sustained release (SR) dosage is such a method, where discharge of drug is achieved for prolonged period. Such tuitions are used to provide a primary dose, obligatory for a usual therapeutic response, trailed by a steady release of the active constituent in quantities appropriate to maintain the required therapeutic reaction for the time required, usually 8-12 hrs. The sustained release drug delivery (SRDD) method has some potential advantage like; sustained release rate, reduction in dose frequency, dose maintenance in plasma, improved patient compliance, reduced toxicity due to overdose, reduction in fluctuation of peak valley concentration. (Isha et al. 2012)
Polymers are used in SRDD because of their quality of self-transforming and longer activity. For decades, polymers have been playing an important role as excipients in tablet and capsule formulation and offer functions such as drug targeting. They are employed successfully in SRDD because of their low molecular weight. (Rao et al. 2012) The use of naturally arising plant based polymers become very imperative in the expansion of SR dosage forms and employed in many preparations based on their molecular weight and properties. Natural polymers are among the most prevalent hydrophilic polymers because they are cheap to run, governing acceptance, non-toxic in nature, reasonable and obtainability. Okra gum, Xanthan gum, Karaya gum, Guar gum etc are the most popular naturally occurring polymers act as thickening agents and drug release retardants used in cosmetics, pharmaceuticals and food products.(Rajamma et al. 2012)
Xanthan gum is extensively used in the formulation of sustained release matrix tablets as it is biodegradable, non-toxic hydrate and swells. Pure culture fermentation procedure of a
carbohydrate with Xanthomonas compestris is used to produce Xanthan gum. It is a sodium, calcium or potassium salt of a high molecular weight polysaccharide having D-glucuronic acid, D-glucose and D-mannose. (Sekhar et al.2011) This gum is selected as it is widely available and cheaper as compared to other polymers currently available (Rajesh et al.2009).
Hypertension is well-defined as a systolic blood pressure of > 140 mm Hg and diastolic blood pressure of>90 mm Hg. Hypertension is threat for myocardial infarction, congestive heart failure, stroke, end stage renal disease and peripheral vascular disease. The World Health Organization stated that suboptimal blood pressure (systolic blood pressure>160) is accountable for 62% of cerebrovascular diseases and 49% of ischemic heart diseases. (Parvathi et al.2012)
Indapamide is a thiazide like diuretic that is lipid soluble and has a long duration of action. It has antihypertensive effect at low doses, while having minimal diuretic effect. It decreases the reabsorption of sodium by inhibiting Na+/Cl- transporter. (Hossain MA et al. 2013). It shows anti-hypertensive activity in SR at a dosage of 1.5mg/day. Pure Indapamide is almost insoluble in water (0.75 mg/l) and poorly absorbed from gastro intestinal tract. Indapamide has half-life of 14-18 hours and poor bioavailability of 30-40%. (Sanam et al. 2012)
Present study was conducted to formulate sustained release dosage form of Indapamide used for the treatment of hypertension using natural polymer xanthan gum as a release retardant material.
Availability: Items available for loan: UVAS Library [Call number: 2204,T] (1).
2.
Detoxification Of Aflatoxins Using Different Organic Acids
by Sana Ejaz (2013-VA-14) | Dr. Mateen Abbas | Dr. Muhammad Tayyab | Dr. Sehrish Firyal.
Material type: ; Literary form:
not fiction
Publisher: 2015Dissertation note: From global prospective of food safety and food security, mycotoxin contamination of foods has gained much attention as potential health hazards for humans and animals. Cereals and other crops are exposed to fungal attack in the field or during storage and this attack may result in mycotoxin contamination of crops. Animal feed is basic necessity for all the live stock, poultry and other animals. AF is the most important for human and animal health perspective and in developing countries such as Pakistan where climate conditions favor the formation of these toxic metabolites. Governments and private organizations of international level have established maximum residue levels (MRIs) which usually guide to control AF in feed. Therefore, the current study was planned to detoxify AF by using different organic acid treatments in animal feed collected from different dairy farms of Punjab.
The samples of cotton seed cake, maize oil cake and animal feed were collected and checked the presence of AFB1 qualitatively by TLC and quantitatively by HPLC. The samples which gave positive results were treated with different acidic treatments applied on it. Firstly checked the results of citric acid, acetic acid and lactic acid on feed sample qualitatively by TLC. TLC plates were checked under UV box and the samples which showed the detoxification of AF were quantitatively analyzed by HPLC in Toxicology Laboratory, QOL, UVAS, Lahore, Pakistan.
The average concentration of AFB1 found in the cotton seed cake, maize oil cake and mixed feed were 279.8 ppb, 34.2 ppb and 25.5 ppb, respectively much greater than permissible levels proposed by European Union. Treatments of varying concentration of citric acid, acetic acid and lactic acid were applied on positive samples (≥20 ppb) and checked their effect on rate of detoxification.
All the above mention treatments applied on the feed samples in order to obtained in vitro detoxification of AFB1. Sprayed different concentration of acetic acid, citric acid and lactic on positive samples by varying volumes and placed them over night then extracted and analyzed.
It has been observed that 1N concentration of citric acid, acetic acid and lactic acid showed complete detoxification. However, when these samples were treated with 0.5N solution of organic acids then variation was seen in rate of detoxification.
Statistically these results were analyzed by ANOVA which showed that effect of these treatments on rate of detoxification was highly significant (P<0.05). In vitro detoxification of AF by these organic acids was proved beneficial in order to reduce the animal and human health risks. However, in vivo detoxification of aflatoxin by using these organic acids should be studied in future.
Availability: Items available for loan: UVAS Library [Call number: 2283-T] (1).
