RELEASE OF C. ALBICANS FROM SKIN 93 with 3.0 ml of DI water, and stained with 0.5 ml calcofl uor white (Difco, Ann Arbor, MI) for 10 to 15 min. The tape strips were again rinsed three times with 3.0 ml DI water and allowed to air dry. Once the tape strips were air-dried, the yeast cells were enumerated visually with an Olympus BH2 fl uorescent microscope (Olympus Corporation, Lake Success, NY) fi tted with a 405 nm excitation fi lter and a 455 nm barrier fi lter. The tape strips were placed with the white crescent label near the bottom edge of a microscope slide, perpendicular to the microscope objective. A 20X objective was used and the slide was positioned so that the fi eld of view bisected the tape strip. Only the cells appearing within the fi eld of view (an area of approximately 2 × 107 μm2) were counted. The fi eld of view represented 5% of the total tape strip area. The percent removal was calculated as follows: number of yeast on control tape strip number of yeast on treated tape strip number of yeast on control tape strip q100 This method estimated approximately 104 yeast cells bound to a 22-mm diameter D-Squame tape strip under the described conditions. Tape strips were evaluated in trip- licate for each condition. Digital photomicrographs were taken with a SPOT Digital Camera (Diagnostic Instruments, Sterling Heights, MI). VIABLE COUNT RELEASE PROTOCOL Skin tape strips produced using the previously described procedure were used to assess the ability of 3–4 μm CMC particles (described in Table I) to release C. albicans from the skin strips. The exposed adhesive on the tape strips was blocked with 2.0 ml of 5% bovine serum albumin (BSA) in PBS and incubated for 60 min at 33°C while shaking at 220 rpm. After the blocking solution was removed, each well was washed three times with potas- sium phosphate buffer (KP), and then 1.0 ml of C. albicans suspension (105 CFU/ml) and 1.0 ml of TSB were added to each tape strip. The plates were incubated at 33°C for 60 min, the fl uid was aspirated, and the tape strips were rinsed three times with 3.0 ml TBS. A suspension of 3–4 μm CMC (2.0 ml 0.25 mg/ml in TBS) was added to each tape strip and 2.0 ml TBS was added to the control. The tape strips were incubated at 25°C while shaking at 220 rpm. At 0, 15, 30, and 60 min after addition of the CMC suspension, fl uid samples were collected from each well (in triplicate) and plated on SAB-DEX agar. The agar plates were then incubated for 24 h at 33°C and the resulting yeast colonies were counted to determine the numbers viable of yeast in each solution. EFFECT OF PH ON RELEASE EFFICACY To determine the potential effect of pH on the release C. albicans from the skin by bath tissue containing CMC particles, skin tape strips were prepared as described previously. The exposed adhesive on the tape strips was then blocked with 2.0 ml of 5% BSA in PBS for 60 min

JOURNAL OF COSMETIC SCIENCE 94 at 33°C while shaking at 220 rpm to cover exposed adhesive. Fluid was removed from each well and washed three times with KP, and then 1.0 ml of C. albicans suspension (105 CFU/ml) and 1.0 ml of TSB were added to each tape strip. The plates were incubated at 33°C for 60 min, the fl uid was aspirated, and the tape strips were rinsed three times with 3.0 ml TBS. CMC (3–4 μm) was suspended (0.25 mg/ml) in each of the following buffers: citrate phosphate (0.1 M pH 4.2, 5.2, and 6.2) TRIS (0.1 M pH 7.2 and 8.2) 4-(2-hydroxyethyl)- 1-piperazineethanesulfonic acid (HEPES) (50 mM pH 6.2, 7.2, and 8.2) or phosphate (50 mM pH 6.2, 7.2 and 8.2). A 2.0 ml sample of each CMC solution was added to one well containing a prepared tape strip, and 2.0 ml of each buffer without CMC were used as controls. The tape strips were then incubated at 25°C while shaking at 220 rpm. At 10-min time intervals after addition of the CMC or buffer control solutions, selected tape strips were rinsed three times with 3.0 ml DI water and fi xed by incubating 2.0 ml of 2.5% glutaraldehyde with each sample for 10 min. The samples were then rinsed three times with 3.0 ml of DI water and stained using 0.5 ml calcofl uor white for 10–15 min. The tape strips were again rinsed three times with 3.0 ml DI water and allowed to air dry. Once the tape strips were dry, the yeast cells were counted microscopically and the per- cent removal calculated using the method and formula described previously. DETERMINATION OF C. ALBICANS GROWTH INHIBITION BY CMC C. albicans (2.0 ml 2 × 105 CFU/ml) in PBS was incubated with either 2.0 ml of 3–4 μm CMC suspension (0.5 mg/ml) or 3–4 μm cellulose–phosphate suspension in TBS (0.5 mg/ml pH 7.2) for 210 min at 33°C. Fluid samples (1 ml) were collected at 0, 15, 30, and 60 min time intervals and plated (in triplicate) on SAB-DEX agar. The agar plates were incubated for 24 h at 33°C and the resulting colonies were counted. PRETREATMENT OF SKIN TAPE STRIPS WITH CMC Tape strips were prepared and the exposed adhesive was blocked with 5% BSA as previ- ously described. Each tape strip was treated with 2.0 ml 3–4 μm CMC suspension (0.25 mg/ml) in TBS for 15 min at 25°C at 220 rpm and then rinsed three times with 3.0 ml TBS. Next, 1.0 ml each of C. albicans suspension (105 CFU/ml) and TSB were added to each tape strip and incubated at 33oC for 60 min. The fl uid was aspirated and the tape strips were rinsed three times with 3.0 ml of TBS. Each tape strip was then fi xed with 2.0 ml of 2.5% glutaraldehyde for 10 min at 25°C while shaking at 220 rpm. The tape strips were then rinsed three times with 3.0 ml of DI water and stained with 0.5 ml calcofl uor white for 10 to 15 min. The tape strips were again rinsed three times with 3.0 ml DI water and allowed to air dry. Once the tape strips were dry, the attached yeast cells were counted microscopically. SIMULTANEOUS ADDITION OF YEAST AND CMC TO SKIN TAPE STRIPS Tape strips were prepared and blocked with 5% BSA as previously described. Each tape strip was then treated with 1.0 ml each of 3–4 μm CMC (0.5 mg/ml) and C. albicans