Sunday, 22 January 2017

Different Acid , Base theories or concepts

(1).Arrhenius theory/concept:-According to Arrhenius theory:                         
*Acids:-Those compounds which are
gives H+ ion in the water solution, 
are called acids.These are sour     
taste , turn blue litmus paper to red
an pH lower then 7.                          
Example:                                              
(a)  HCl     ⇌    H+    +     Cl-            

(b)   H2So4     ⇌     H+   +     HSo4-

*Bases:-Those compounds which are gives OH-  ion in the water solution called base. These are bitter in taste
and,turn red litmus paper to blue ,     
and pH higher than 7.                            Examples:                                                  (a)   NaOH     ⇌   Na+      +     OH-  

      (b)   Ca(OH)2    ⇌   Ca2+      +   2 OH-
 
This theory was related because it 
Could not respected the acidic and 
basic character are substance.       

   (2). Bronsted Or Lowery theory/                   concept(1923):-                                             'Bronsted' theory purpose the new              theory in - 1923 and 'Lowery'  also        
   give same theory independently :             
   * Acid:According to this concept an    
      acid is a substance that can 'donate'      the proton (H+ ion proton donor).     
Example:                                             
These proton are not in the 'freedom'
state in the water solution.These are 
react with water molecule and produce
the hydronium ion(H3O ion).               

(a)  H+    +   H2O     ⇌     H3O+           

(b)    HCl    ⇌    H+   +     Cl-                 

  *Base: According to Bronsted or Lowery    theory : Base is a substance that can       'accept the proton' are called base and     these base are called 'proton acceptor'
Example:                                                

NH3   +    H3O    ⇌   NH4+    +   H2O   


(3). Lewis's Theory/concept(1939):-     
According to Lewis's  theory :                

  *Acid: Those  acids which can 'accept        a pair of electron' and 'make a Co-             ordinate bond' , called acids.Thesre           acids are electron pair acceptor.                                                    
 *Base:Those base which can 'donate         a pair of electron' to form a Co-ordinate
 bond , called lewis base.These base are 'electron pair donor'.                                  

Saturday, 21 January 2017

Drug stability

Drug stability means the ability of the Pharmaceutical dosage forms to maintain the physical,chemical, therapeutic , and microbial properties during the time of storage and usage by the patients.
It is measured by the rate of changes that take place in the pharmaceutical dosage forms.
Expiry Date means that drug can not be used after this date because the concentration of drug is decreased and become lower than therapeutic concentration.
For example:(1) Tablets and capsules remain stable in package , but after removal the expiry date will change.
(2)Eye drops can be used for one month after opening the droppers.



Non-aqueous titration



It is a substance which are either too weakly acid,acidic or too weekly basics do not produce sharp and point in aqueous solution but they can be titrated in non-aqueous medium.
OR
Non-aqueous titration are those , in which the titration of weakly acidic or basic substance are carried out using non-aqueous solvents .So as to get sharp and points .
Such titration can also used for the titration of substance not soluble in water.
A solvent and changed the majo of making it strongly /weakly equal ionisation.
EXAMPLES:-(1)HCl in water is strongly acidic but HCl in acetic acid is weakly acidic.
(2)Acetic acid (CH3COOH) is weakly in water but strongly acidic in ammonium solution (NH3OH).
These acidic/basic character can be entered by the use of approximately solution.

TYPES OF SOLVENTS:-

These solvents are of following types ,classified according to their properties as:
1.Aprotic solvents
2.Protogenic solvents
3.Protophillic solvents
4.Amphiprotic solvents etc.

(1)Aprotic Solvents:-                                                                                                                    

These are solvents which are involve innert, are not in any chemical reations.
They do not fevoure ionisation.
Example: Benzene, chloroform, petrolium ether .

(2)Protogenic Solvents:- 

These are acidic solvents and yield portion.
Example: Hydrochloric acid (HCl).

(3)Protophillic Solvents:- 

These are basic in nature and can extract/accept from acids.
Examples: Sodium hydroxide solution (NaOH), ammonia solution(NH3 solution), pyridine solution.

(4)Amphiprotic solvents:- 

These solvents have both protogenic and protophillic properties.
Example: water(H2O), alcohol(OH),acetic acid(CH3COOH).

OTHER SOLVENTS:- 

1. Lavelling Solvents:- 

A strongly basic solvent has strong tendency to accept proton and  a weakly basic solvent (protophillic solvent) has weaker tendency to accept proton.

A strongly basic solvent is called as levelling solvent for weak and strong acid because it can accept proton from any acid rather it is strong acid and weak acid.

2. Differentiating solvents:-

A weakly basic solvent has weak tendency to accept proton ,hence these solvents is called as differentiating solvents , because it can accept proton from and not extract from weakly acid ,this effect is called as differentiating effect.

Similarly weakly acidic substance are called differentiating solvents.




Wednesday, 18 January 2017

synonyms,biological source,geographical source,preparation,description,chemical constituent,uses of Ginseng

GINSENG Plant
  Synonyms of Ginseng:-
synonys of Ginseng are panax, pannag, ninjin, energofit etc.

    Family of Ginseng:- Araliaceae.                                                                      
Biological source of Ginseng:- 
Ginseng is the dried root of different natyrally occuring species of panax (panax ginseng).                                                                                  
Geographical source of  Ginseng:- 
This plant of Ginseng is found in Russia , Korea, China but cultivated the large commercial scale of Ginseng in Japan , Canada and in United State(U.S).                                                                                                                         
 Preparation of Ginseng:- 
Ginseng plant are usually harvested 3-5 years after transplanation.it is usual practice to affect the actual hervesting between July - October .
Mostly these Ginseng plants are of two types , namely as 
1.white Ginseng , 2. Red Ginseng.

 Description of Ginseng:-                       
Color: yellowish-brown, white or red.
Odour: none                                              
Shape: Tuberous and corpulant .          
Apperance: transulant, and bears the stem scars.

Chemical constituents of Ginseng:-
The Ginseng comprises of a complex mixture of 'Triterpenoid'.saponins which may be either a steroidal triterpene or a pentacyclic related to oleonic acid.mostly these glycosides are classified as: ginsenosides, panaxosides, and chickusetu saponins etc.

Uses of Ginseng:- 
The following uses of Ginsengs are:
1.Ginseng is used for treatment of gastric problems.                      
2.Ginseng is used as a tonic for heart diseases.                                        
3.Mostly Ginseng is used for anaemia and diabetes etc.                             
4.Ginseng is a energyfull plant for health.                                                      
5.Ginseng root is used for treatment of sexual importance.                             

                                    

  
                                     

Degradative pathway of drugs

Deradative pathway of drugs:
Decomposition of active ingredients in liquid, semi-solid and solid dosage forms can occurs through hydrolysis, hydrolytic degradation of the drug is catalysed by    the acid and basic species of the buffer salt in addition to H+ and oH- , the buffer concentration should be kept at a  minimum.                                                   
The degradation of a drug , depends on following parameters:
(1)Types of solvents                             
(2)Complexation                              
           (3)Surfactants                                        
    (4)Modification of chemical structure
 (5)Transient derivatives          
 
                                                                                                             
       (1)Types of solvents:-                                                                                                                        
   Partial or full replacement of water  with a solvent of lower dielectric  constant generally cause a considerable decrease in the rate hydrolysis.                                              
* Examples: of these non-aqueous solvents are ethanol, glycols, glucose and manitole solutions and submitted amides.                                                                              

(2)Complexation:-                                                                                               

The hydrolytic rate may be influence     influenced in two ways by complex   formation , namely , by either Polar or Stearic effects.                                        
Example:    Caffeine.

  (3)Surfactants:-

 Anionic,cationic and non-ionic surfactants also stablize the drugs agains base    catalysis.                                                                                                     
* The use of anionic surfactants (5%  solution of sodium lauryl sulphate)          
cause a 18-folds increase in the half-life of benzocaine.                                             
 * The use of cationic surfactants (2.46% solution of Cetrimide ) cause a 10- folds increase in half- life of benzocaine.                                                                   
The use of non-ionic surfactants (3%  solution cause a 4-5 folds increse in half- life of benzocaine.                                                                                                                    
        

(4)Modifications of chemical structures:-                                                                                  

Certain substance added to alkyl or acyl chain of aliphatic or aromatic esters causes a decrease in the hydrolytic rate due to stearic or polar effects .                                        

(5) Transient derdivatives:-                                                                                                           

The stability of pharmaceutical undergoining degradation through hydrolysis could be improved by reducing their solubility by forming less soluble salts or easters of the drugs.
 Also read:Drug stability
      

   
      
                             

Saturday, 14 January 2017

Pharmacology of Antiarhythmic drugs

Antiarhythmic drugs / agents are a group of  cardiovascular drugs , that are used to suppress rhythm of the heart such as atrial fibrilation, atrial flutter, ventricular trachycardia and ventricular fibrication etc.

 Classification of Antiarhythmic drugs:-
 These antiarhythmic drugs are classified according to classes:

 *Class first:
These agents interference with sodium channel(Na+)
 examples: procainamide , lidocaine

*Class second: 
These agents are anti-parasympathetic nervous system agents in this class beta blocker
examples: metoprolol , atenolol , propranolol

*class third:
These agents are affects of potassium channel(K+) reflux.
Examples: sotlol , prefylium .

*class fourth:
These agents are slow calcium channel (Ca++) blockers.
Exapmles: diltiazem , verapamil .

*class fivth:
These agents are work by unknown mechanisms.
Examplrs: digoxin , adenosine , magnisium.








Friday, 6 January 2017

Geographical indication of good (registration & provision ) act 1999(Subject- pharmaceutical jurisprudence & intellectual property rights)


The Geographical indication of good act was passed in 1999.
Geographical indication in relation to good means an indication ,which identifies such goods as:
Agriculture goods,natural goods,manufactured goods etc. is originating or manufactured in territory of a country.
Geographical indication have been used in India for a wide variety of product such as:
Basmati rice,
Darjeeling tea,
Kangra tea,
Feni ,
Alphonso mango,
Coorg cardamom ,
Kanchipuram silk saree,
Kohlapuri chappals etc.
The registration and condition for registration and protection:
The controller general of patents,design,trademark
Appointed under section -1 of section-3 of the Trademark act 1999. shall be register of geographical indication .
These are devided in two conditions , these conditions are
(1)Registration to be in respect of particular goods and area.
(2)Prohibition of registration of certain geographical indication.
 also read:Trademark act 1999

 

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