# Encapsulation of Rose Extract in Polyurethane Structures Modified for Enhanced Aqueous Solubility  
[PERSON]  
1 Department XI (Pediatrics II), Faculty of Medicine, \"[PERSON]\" University of Medicine and Pharmacy Timisoara, 2E. Murgu St., 300041 Timisoara, Romania; [EMAIL_ADDRESS]  
[PERSON]  
2 Department V (Internal Medicine I), Faculty of Medicine, \"[PERSON]\" University of Medicine and Pharmacy Timisoara, 12 Revolutiieti dni 1989 Blvd., 300041 Timisoara, Romania  
2 Department V (Internal Medicine I), Faculty of Medicine, \"[PERSON]\" University of Medicine and Pharmacy Timisoara, 12 Revolutiie dni 1989 Blvd.  
oral mucosal membranes, can sometimes be mistaken for other conditions, such as oral herpes simplex virus infection, or linked to systemic disorders, with their causes often being complex and multifactorial, involving factors such as genetic susceptibility, stress, hormone fluctuations, local trauma, and environmental variables [4].  
Within the Rosaceae family, the genus Rosa comprises the woody perennial flowers known as roses; over 100 species and thousands of cultivars exist. These plants can be classified as trailing, climbing, or upright and are often characterized by prickly stems [5]. Herbal dentistry is acknowledged for its potential advantages in treating oral problems and encouraging good hygiene, indicating that natural materials such as rose extract may be advantageous because of their innate qualities; the extract may offer antimicrobial, anti-inflammatory, analgesic, and antioxidant properties [6]. Glycosides, alkaloids, flavonoids, anthocyanins, counarnins, phenolic compounds, quinones, tannins, and terpenoids are among the many substances found in rose flower extracts [7]. Rose petal extract does, however, have certain disadvantages in addition to advantages. One such disadvantage is the possibility of allergic responses (skin rashes and itching), which is why its encapsulation may be useful in some therapeutic applications.  
The advantages of nanotechnology have led to the development of many polymeric carriers for the encapsulation of natural extracts and synthetic drugs. The choice of the delivery systems is determined by how well they can protect the loaded active agent from outside influences, change its characteristics (such solubility in water), and improve its release [8]. Polyurethanes (PUs), a class of macromolecular compounds that contain carbamate/urethane functional groups that are obtained through the reaction between isocyanates and alcohols, have numerous applications in the pharmaceutical and medical industries; these applications include catheters, wound dressings, artificial skin, cardiac valves, drug carriers, and implants used in bone reconstruction [9].  
Among the earliest controlled-release PU formulations are those used for prednisolone [10], iodine-based compounds [11], propranolol [12], anticancer drugs [13], isoniazid, rifampicin, and novocain [14]. A modified recipe for synthesizing PU carriers, which employs a polyaddition process combined with simultaneous emulsification, was developed by our team, based on the method described by [PERSON] [15]; this approach resulted in the creation of various PU delivery systems [16; 17; 18; 19; 20; 21], but the limited aqueous solubility of the resulting structures posed a significant drawback. This study aims towards the synthesis and evaluation of PU structures with an improved aqueous solubility that can be used as a transdermal carrier for a rose extract. The use of a natural catalyst to produce a PU carrier for rose extract is novel in this study; as is well known, catalysts used in the PU industry usually consist of organometallic compounds containing heavy metals that are dangerous or highly reactive tertiary amines that can cause severe irritation.