Formulation and Evaluation of Pre-Bath Derma Gel for Protection Against Hard Water

Patel Azba Siddiq*, Meman Manatasha Riyazbhai, Patel Samiya Mustakali, Patel Savda Sajid, Pardeshi Shivani Santosh, A.M. Danish

JIIU’S Ali Allana College of Pharmacy, Akkalkuwa. Dist- Nandurbar, Maharashtra, India

*Correspondence: azbapatel4@gmail.com

DOI: https://doi.org/10.71431/IJRPAS.2026.5707        

INTRODUCTION

Water with high concentrations of divalent metal ions, mainly calcium (Ca²⁺) and magnesium (Mg²⁺), is referred to as hard water. Millions of people worldwide suffer from water hardness, an environmental problem that has drawn more attention because of its effects on dermatological health.[1, 3, 4, 14] Hard water contact has been shown in numerous epidemiological and experimental investigations to significantly damage the function of the skin barrier, resulting in dryness, irritation, itching, and an increased vulnerability to inflammatory skin conditions including atopic dermatitis.[7, 9, 10, 11]

The main defense against environmental assaults and excessive water loss is the skin barrier, especially the stratum corneum.[7,8,9] Preserving hydration, avoiding microbial invasion, and guaranteeing appropriate physiological function all depend on maintaining an intact skin barrier.[7,8,19] Through physicochemical interactions between calcium and magnesium ions and skin surface lipids, prolonged exposure to hard water can negatively impact this protective barrier.[9, 10, 11] These interactions may enhance transepidermal water loss (TEWL), change the stratum corneum's structural arrangement, and jeopardize the integrity of the skin as a whole.[7, 9, 19]

According to earlier studies, washing with hard water increases the amount of surfactants that are deposited on the skin's surface.[6, 10] Soap scum is a term used to describe the insoluble precipitates that are created when mineral ions interact with cleaning chemicals [3,6,14]. After washing, these deposits stay on the skin and could cause irritation, damage to the skin's barrier, and a delayed healing process.[10,11] Additional experimental research has shown that those who are exposed to hard water have more dry and irritated skin than people who are exposed to soft water.[10, 11]

Ion-exchange systems, reverse osmosis units, and chemical treatment techniques are examples of water-softening technologies that are now used to manage hard water.[1,4,14] Despite their effectiveness in lowering water hardness, these methods are frequently costly, necessitate installation and upkeep, and are not easily available to all communities. Moreover, instead of offering direct skin protection, these systems concentrate on altering the water's quality [1,14]. As a result, there is still a need for straightforward, affordable, and approachable methods that can reduce the dermatological consequences of hard water exposure.

Preventive dermatology has become a significant field of study that focuses on safeguarding against environmental harm prior to the onset of symptoms.[2,5,15] Barrier-based topical formulations have received a lot of interest within this context.[2, 15, 24] Barrier formulations are intended to avoid disruption of skin physiology by establishing a protective interface between the skin and external irritants, in contrast to therapeutic preparations that treat established skin damage.[2,15] These formulations have shown promise in maintaining the function of the epidermal barrier and lowering exposure to external stresses.

Pre-bath skin barrier formulations are a unique preventive strategy designed to be applied prior to harsh water exposure. The idea is for the skin's surface to develop a thin, consistent, and washable protective layer. This layer reduces mineral deposition and protects skin lipids by acting as a physical barrier that minimizes direct interaction between mineral ions and epidermal components.[15,24] Incorporating humectants and skin-conditioning agents may also increase overall skin comfort during and after bathing and promote moisture retention.[22, 24]

Because of their high water content, non-greasy texture, simplicity of application, and superior patient acceptability, hydrogels are especially well-suited for these kinds of applications.[16, 17, 25, 36] Because of their superior viscosity-building qualities, clarity, stability, and capacity to form cohesive films on biological surfaces, carbopol-based hydrogels are frequently used in topical medicinal and cosmetic formulations.[16, 18, 21, 25, 36] These features allow the formulation to stay on the skin for a longer period of time without compromising user comfort.

A pre-bath barrier gel's protective effectiveness can be further increased by adding multipurpose substances. As a humectant, glycerin draws and holds moisture in the stratum corneum, lessening the dryness brought on by exposure to harsh water.[22,24,40] Potassium alum may help lessen mineral interactions on the skin's surface and has mildly astringent qualities.[2,21,38] Herbal components with calming, antioxidant, and skin-conditioning properties, such Ziziphus jujuba leaf extract, can promote barrier healing and enhance skin resistance to environmental stress.[35]

Few studies have concentrated on the creation of specific pre-bath protection formulations integrating hydrogel technology, mineral-control techniques, and herbal actives, despite a large body of data on hard water and skin barrier dysfunction. The body of research indicates that there is a significant lack of readily available, reasonably priced preventive products that are expressly made to protect people against hard water exposure on a regular basis.

In order to create and assess a novel pre-bath skin barrier gel with Carbopol 940, glycerin, potassium alum, and Ziziphus jujuba leaf extract, the current study was conducted. The formulation was created to maintain good physicochemical qualities, skin compatibility, stability, and user acceptance while offering a protective barrier against exposure to harsh water. The study also sought to evaluate this preventive strategy's potential as a workable and economical way to lessen skin damage caused by hard water.

MATERIALS AND METHODS

Study Design

The present work was an experimental formulation-development study aimed at developing and evaluating a pre-bath skin barrier gel for protection against the adverse effects of hard water exposure.[10] The study involved formulation of a Carbopol-based hydrogel containing potassium alum and Ziziphus jujuba leaf extract, followed by evaluation of its physicochemical properties, stability, and suitability for topical application.[25]

Table 1. Formulation Composition

Method of Preparation

1. Carbopol 940 (1.5 g) was accurately weighed and gradually dispersed in a sufficient quantity of distilled water with continuous stirring to avoid lump formation.
2. The Carbopol dispersion was allowed to stand for complete hydration and swelling of the polymer.
3. In a separate beaker, glycerin (6 mL) was mixed with a small quantity of distilled water to obtain a clear solution.
4. Methyl paraben (0.15 g) and propyl paraben (0.02 g) were dissolved and added to the glycerin solution with continuous stirring.
5. Potassium alum (0.5 g) was dissolved separately in distilled water and added slowly to the above mixture under constant stirring.
6. The previously prepared Ziziphus jujuba leaf extract (2 mL) was incorporated into the formulation and mixed thoroughly until a homogeneous mixture was obtained.
7. The hydrated Carbopol dispersion was combined with the prepared mixture and stirred continuously to ensure uniform distribution of all ingredients.
8. Triethanolamine was added dropwise with gentle stirring until gel formation occurred and the desired consistency was achieved.
9. The final volume was adjusted with distilled water to obtain a total weight of 30 g.
10. The gel was stirred continuously until a smooth, homogeneous, and air-bubble-free preparation was obtained.
11. The prepared gel was transferred into clean, airtight containers and stored at room temperature until further evaluation.

Evaluation of the Formulation

Organoleptic Evaluation

1. A sample of the prepared gel was visually inspected.
2. Colour, appearance, consistency, homogeneity, and the presence of particulate matter were observed and recorded.
3. The observations were used to assess the aesthetic acceptability of the formulation.

Determination of pH

1. Approximately 1 g of gel was dispersed in distilled water.
2. The pH meter was calibrated before use.
3. The pH of the dispersion was measured at room temperature using a digital pH meter.
4. Measurements were performed in triplicate and the mean value was recorded.[27,29]

Spreadability

1. A fixed quantity of gel was placed between two clean glass slides.
2. A standard weight was placed on the upper slide.
3. The time required for the upper slide to move a specified distance was recorded.
4. Spreadability was calculated using the following equation:

S = (M × L) / T[31]

Where:
S = Spreadability
M = Weight tied to the upper slide (g)
L = Length moved by the slide (cm)
T = Time taken (s)

Extrudability

1. The gel was filled into a collapsible tube.
2. A constant force was applied to the tube.
3. The amount of gel extruded from the tube was observed and recorded.
4. Extrudability was assessed based on the ease of extrusion.[16,25]

Washability

1. A small quantity of gel was applied to the skin surface.
2. The applied area was washed with water.
3. Ease of removal and the presence or absence of residue were observed and recorded.

Homogeneity

1. The gel was visually inspected and manually examined.
2. The formulation was checked for uniform consistency.
3. The presence of lumps, aggregates, or phase separation was noted.[25]

Skin Irritation Test

1. A small quantity of gel was applied to a limited area of skin.
2. The application site was observed for a specified period.
3. Signs of irritation such as redness, itching, burning sensation, swelling, or discomfort were monitored.
4. Observations were recorded to evaluate dermatological safety.[15]

Stability Study

1. The prepared gel was stored under different storage conditions.
2. Samples were evaluated at predetermined time intervals.
3. Changes in appearance, colour, consistency, pH, homogeneity, and phase separation were observed.
4. Stability data were recorded and compared throughout the study period.[26,25]

RESULT AND EVALUATION

Physical Appearance

The color, clarity, homogeneity, consistency, and presence of any visible particle matter were assessed for the manufactured gel compositions. Every formulation had acceptable physical properties and showed no signs of aggregation, phase separation, or lumps. The gels' apparent clarity suggested that the formulation's ingredients were evenly distributed and that Carbopol 940 had been properly hydrated. Formulation F3 showed a minor opacity, which might be explained by the increased viscosity and light scattering caused by the higher polymer concentration in the gel matrix. These results point to acceptable aesthetic qualities and high formulation stability for topical application. [25]

Table 2. Physical Appearance of Pre-Bath Skin Barrier Gel

pH Evaluation

To ascertain whether the produced gels were compatible with the physiological pH of the skin, which normally ranges from 4.5 to 6.5, their pH was assessed. The pH values of Formulations F1, F2, and F3 were determined to be 5.1, 4.0, and 5.9, respectively. The observed pH values, which demonstrate that the formulations were within or close to the acceptable range for topical usage, indicate good skin compatibility. The somewhat lower pH of F2 in comparison to F1 and F3 may be due to differences in triethanolamine's capacity to neutralize carbopol. The polymer becomes ionized when carbopol is correctly neutralized, stabilizing the gel and maintaining the pH balance. To maintain the integrity of the epidermal barrier, reduce irritation, and support normal skin physiology, the pH must be kept around that of normal skin.

Spreadability Study

One crucial factor that affects how easily a gel can be evenly applied to the skin's surface is its spreadability. Formulations F1, F2, and F3 were found to have spreadability values of 6.7 cm, 6.5 cm, and 6.3 cm, respectively. Good consistency and ease of application were demonstrated by the satisfactory spreadability of all formulations. As gel viscosity increased, spreadability gradually decreased, which may be explained by the higher polymer content and consequent rise in internal flow resistance. Because of its relatively lower viscosity, formulation F1 had the highest spreadability, while formulation F3's denser gel structure resulted in somewhat poorer spreadability. Formulation F2 showed balanced spreadability, guaranteeing consistent application and sufficient skin coverage.

Proper spreadability is essential for the formation of a continuous protective film on the skin surface, thereby enhancing protection against hard-water-induced mineral deposition and improving patient compliance. [16,18,31]

Extrudability Study

A key factor in determining how easily a gel may be dispensed from its container and applied to the skin is its extrudability. The developed formulations displayed good extrudability, creating a homogeneous ribbon of gel with moderate extrusion force. The observed extrusion behaviour indicates that the formulations possessed an appropriate viscosity, allowing smooth dispensing without uncontrolled flow or undue resistance. Uniform extrusion enables accurate dose, easier application, and enhanced patient compliance. [16,25]

Washability Test

Since pre-bath formulations are meant to offer short-term protection prior to bathing and should be easily removed during routine washing, washability is a crucial feature. Excellent washability was demonstrated by the produced gel, which was easily removed from the skin's surface without leaving any noticeable residue. The hydrogel nature of the formulation, which enables quick dissolving and removal with water, may be responsible for this behavior. Easy washability guarantees that the formulation fulfills its protective role without interfering with regular cleaning procedures, increases user acceptability, and reduces the danger of pore blockage or pain. These findings confirm the suitability of the developed gel for pre-bath application.[16,17]

Skin Irritation Test

To assess the new formulation's safety and suitability for topical application, a skin irritation study was conducted. Throughout the trial period, no symptoms of erythema, itching, burning, swelling, or other negative reactions were noted, suggesting that the formulation was well-tolerated by the skin and not irritating. Maintaining a skin-compatible pH and using biocompatible excipients like Carbopol 940, glycerin, and Ziziphus jujuba leaf extract may be responsible for the lack of irritation. The herbal extract's antioxidant and skin-conditioning qualities may also help to increase skin comfort and lessen irritation. These results imply that the created gel is safe for dermatological use and appropriate for regular topical use. [7,15,18,35]

Protective Performance (Qualitative Assessment)

By applying the formulation to the skin before exposure to hard water, the produced gel's protective efficacy was assessed qualitatively. The composition showed promise as a pre-bath skin barrier gel by exhibiting excellent protective function. The development of a thin hydrogel coating on the skin's surface, which can reduce direct contact between epidermal tissues and hardness-causing minerals like calcium and magnesium ions, may be responsible for the observed protective effect. This protective layer may lessen mineral deposition brought on by exposure to hard water and assist maintain the integrity of the skin barrier. Additionally, glycerin helps maintain skin hydration and moisture retention, and potassium alum's mildly astringent qualities may offer additional protective benefits. Collectively, these findings support the potential utility of the developed formulation as a preventive strategy against hard-water-induced skin discomfort and barrier disruption. [10,15,22,24]

CONCLUSION

The current study effectively created a pre-bath skin barrier gel with glycerin, potassium alum, Carbopol 940, and leaf extract from Ziziphus jujuba. The purpose of the formulation was to preserve the skin before bathing, especially when hard water is present, which is known to cause dryness, irritation, and pain.[7, 10, 11] Acceptable pH, good spreadability, homogeneity, washability, and general stability were among the physicochemical characteristics of the produced gel that demonstrated the formulation's suitability for topical application.

Glycerin served as a humectant to promote skin hydration, and the addition of Carbopol 940 produced the required gel consistency and barrier-forming capacity.[22,24] Ziziphus jujuba leaf extract offered a natural herbal component with potential skin-beneficial activity, while potassium alum added to the formulation's astringent and protective qualities.[35] By lowering moisture loss, enhancing skin comfort, and bolstering the skin's natural barrier function during bathing, the combined action of these substances implies that the created gel may help decrease the negative consequences of hard-water exposure.[7,9,10,24]

The formulation may be regarded as a pre-bath protective preparation that is safe, affordable, and efficient based on the evaluation results. The study shows how herbal and polymer-based substances can be combined to create a topical barrier solution that protects the skin. To establish its long-term performance, safety, and clinical efficacy under actual bathing conditions, more research is necessary.

FUTURE SCOPE

Even though the current study produced encouraging results, more research is required to confirm the formulation and bolster its usefulness. Extended stability tests under various storage circumstances should be part of future research to ascertain the gel's long-term chemical and physical integrity. To determine the formulation's resistance to microbial contamination during storage and usage, microbiological evaluation is also advised.

To assess the gel's true protective impact against hard water-induced skin dryness, irritation, and barrier breakdown, in vivo experiments with human volunteers should be carried out. Such clinical trials would offer more solid proof of the formulation's effectiveness, safety, and tolerability. To enhance the gel's protective effectiveness, texture, and user acceptance, future studies might concentrate on maximizing the content of Ziziphus jujuba leaf extract and additional excipients.

It may be possible to determine the relative benefits of the created formulation by conducting additional comparison trials with commercially available skin barrier products. Examining the formulation's efficacy under a range of bathing circumstances and water hardness levels might also be beneficial. The proposed pre-bath gel has the potential to be used more widely as a dermatological protection product with further development and validation.

ACKNOWLEDGEMENT:

We would like to express my special gratitude to Dr. G. J. Khan, Principal, JIIU'S Ali Allana College of Pharmacy Akkalkuwa and Management of Jamia Islamia Ishaatul Uloom Akkalkuwa for their continuous motivation and providing all necessary facilities during completion of this work.

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