1. INTRODUCTION:

The thumb anatomy and physiology structured to do a wide range of motion, enables to pinch, grip and grasp objects. The 40 percent of hand function performed by thumb. In general at the thumb basilar joint, the cartilage shelters the ends of the bones works as a cushion and permits the bones to skate softly against each other. The more joint damage of thumb arthritis caused by the cartilage surrounds over the ends of the bones deteriorates, smooth surfaces get hardens and the bones then rub against each other (1). The thumb arthritis most common symptom is pain at the base of thumb during daily works, such as holding basket, while writing or turning a key. Other symptoms noticed are stiffness, tenderness or swelling at the thumb base. Usual range of motion or strength of thumb affected.

The 8-12 percent of population affected by thumb arthritis. Thumb arthritis leads to hand arthritis. Non-steroidal anti-inflammatory medications such as ibuprofen, diclofenac, acetaminophen are useful (2). The topical gel is significant dosage forms in drug delivery system in the treatment of transdermal drug delivery. The basal layer of epidermis get permeated in topical dosage forms such as gel and cream. The gel formulation gives good patient compliance (3-4).

2. MATERIAL AND METHODS:

Materials:

Diclofenac sodium was obtained from Fourrts India Laboratories, Chennai, India. Xanthan gum was obtained as generous gift samples from Madras Pharmaceuticals, Chennai, India. Other materials used in the study (propylene glycol, methanol, ethanol, potassium dihydrogen phosphate, etc.) were of analytical grade and procured from SD Fine Chemicals, India. Purified water was used throughout the study.

Formulation preparation:

The composition of different gel formulations of code A1, A2, A3 and A4 were shown in Table 1 and evaluated physical chemical measurements (5-6).

Xanthan gum gels:

The xanthan gum was dispersed in purified water to make viscous solution, the diclofenac sodium dissolved in water and dissolved in menthol, propylene glycol and ethanol and mixed with xanthan gum solution with continuous stirring at 37ºC until the gel was formed (1 h 30 mints).

Drug Content:

The Ultra violet spectroscopy used to evaluate diclofenac content in the gel formulation 50% w/w. The phosphate buffer pH 6.8 is used as bulk, the 1gm equivalent diclofenac gel taken from the formulation. The suitable dilution with the bulk solution cum purified water estimated drug content of diclofenac after the filtration through 0.45micron filter. The estimation repeated three times. The λmax used for UV estimation is 276 nm. The diclofenac content in percentage given in Table 2.

Viscosity measurements:

A Brookfield Digital Viscometer was used to measure the viscosity (in cps) of the formulations. The spindle was rotated at 10 rpm. Samples of the gels were allowed to settle over 30 minutes with the temperature (25 ± 1°C) before the estimation. The experiment repeated three times.

pH measurement:

All gel formulations showed a pH range of 6.4-6.9.

Stability studies:

The samples kept in empty tubes, and kept in the temperature 40ºC and 65% relative humidity for 1 month, 2 months, and 3 months. There is no physical change during analysis and homogeneity was observed in all formulations. The pH found the same during preparation and to the entire time period of the analysis.

In vitro diffusion studies:

The modified kesary chien diffusion cell apparatus used to find the in vitro drug (diclofenac) release from the gel formulation. The diclofenac 80mg equivalent gel formulation used for the analysis. The drug release of all the formulation found in the range of 92-98% in 2 hours.

Table 1. Composition of gel formulations (% w/w)

S. No	Materials	Code
S. No	Materials	A1	A2	A3	A4
1	Diclofenac Sodium	2	2	2	2
2	Acetone	10	10	10	10
3	Xanthan gum	1	2	3	4
4	Propylene glycol	5	5	5	5
5	Menthol	1	1	1	1
6	Ethanol	20	20	20	20
7	Purified water Q.S to make	50	50	50	50

Table 2. Diclofenac Content (% w/w)

S. No	Materials	Diclofenac (%)
S. No	Materials	1	2	3
1	A1	94.9	95.2	95.2
2	A2	94.6	96.1	96.0
3	A3	95.8	97.1	97.2
4	A4	96.7	98.1	98.4

Table 2. Diclofenac Viscosity

S. No	Materials	Viscosity η (cps × 10³ )^a
S. No	Materials	1	2	3
1	A1	101	98	102
2	A2	102	104	104
3	A3	103	105	106
4	A4	108	109	110

^aMean ± SD; n = 3

3. CONCLUSION:

Peoples used to refer horoscope to treat patients is wrong, browsing online horoscope, and online medicines in wrong manner not giving good output. The right physician is essential for every patient. Therefore, peoples take medicines with authorized physician. The prepared formulation is efficient to treat thumb arthritis. The gel formulation viscosity produces smooth penetration through the skin and release a drug in the thumb joint. Further clinical studies in future produces the best use gel formulation to treat thumb arthritis and hand arthritis.

4. ACKNOWLEDGEMENT:

I express my gratitude to Dr. K. Sathishkumar, Dr.R. Parthiban, and Dr. S. Salivahanan, Department of chemical engineering, SSN college of engineering, Kalavakkam, Chennai, Tamilnadu, India.I express my sincere thanks to Shasun Pharmaceuticals, Periyakalapet, Puducherry and Pharma R&D, Biological Evans Ltd, Azamabad, Hyderabad. I express my honour Dr.K.S. Lakshmi, Dr.K. Ilango, Dr.V. Chitra, Dr.N. Damodharan, and Dr.S. Abimanyu, SRM College of Pharmacy, SRM Institute of Science and Technology. I express my thanks and honour to Dr.R. Sundhararajan, Dr. C. Ronald Darwin, Mohamed Sathak A J College of Pharmacy. I express my sincere thanks to Dr. Arivudai Nambi, Novel Laboratories, Mr. Senthil Manickam, Granules india, and Mr. Sasidar Lingala, Shasun Pharmaceuticals.

5. REFERENCES:

1. https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-q-and-a-treating-thumb-arthritis/, assessed on 12/01/2020, 10.00AM.

2. https://www.webmd.com/drugs/2/drug-22221-4289/diclofenac-sodium-topical/diclofenac-3-topical/details, assessed on 12/01/2020, 12.00AM.

3. Formulation and Evaluation of Topical Gel of Lornoxicam Using a Range of Penetration Enhancers, Mundada M.S, Wankhede S.S Patwardhan S.K and Avachat A.M, India Journal of Pharmaceutical Education & Research, 2013; 47(2):168-171.

4. Formulation and evaluation of topical gel of meloxicam, Loveleenpreet kaur and Prabhjot kaur, International journal of research in pharmacy and chemistry, 2014; 4(3), 619-623.

5. Preparation and evaluation of diltiazem hydrochloride diffusion-controlled transdermal delivery system, Limpongsa E, Umprayn K. AAPS PharmSciTech., 2008;9(2):464-70.

6. Formulation and Characterization of Ketoprofen Emulgels, Ramakanth Ambala, Sateesh Kumar Vemula, Journal of Applied Pharmaceutical Science, 2015; 5(7):112-117.

Received on 21.01.2020 Modified on 03.03.2020

Asian J. Res. Pharm. Sci. 2020; 10(4):239-240.

DOI: 10.5958/2231-5659.2020.00043.0