JOURNAL OF COSMETIC SCIENCE 98 greatly impact the integrity of the stratum corneum barrier and potentially cause skin irritation (24). Electrostatic removal of contaminants from the skin surface, using negatively charged particles to reduce the attractive forces between the contaminant and the skin, offers a potential method to clean the skin with reduced risk of skin irritation. Negatively charged CMC particles (3–4 μm), as well as other anionic materials or cationic exchangers, in close proximity to the attached microbe appear to act electrostatically on the skin tape strips and attached C. albicans with suffi cient strength to overcome the combined binding affi n- ity between them (Figures 1 and 3). The released microbe can then be transferred to the cleaning substrate (wipe, diaper, cloth) to facilitate contaminant removal. The CMC mi- croparticles do not exhibit biocidal or biostatic properties (Table IV) and are not antici- pated to have harsh or damaging effects on the skin. C. albicans, a causative agent of diaper rash known to have multiple mechanisms (electro- static, hydrophobic, and adhesin interactions) of attachment to mammalian skin (4,12,15), was removed from skin cells bound to a tape strip by what appears to be an electrostatic interaction (Figures 1 and 3). After a 10-min exposure to the CMC particles, greater than 95% of the bound yeast was removed from the skin tape strips (Table II) based on visual Figure 5. Effects of pH on removal of yeast from tape strips using 3–4 um CMC particles (0.25 mg/ml) as determined by visual counts ▼ = Citrate-Phosphate Buffer ♦ = Phosphate Buffer ▲= HEPES Buffer ■ = TRIS Buffer Bars = SD (n=3). Table IV Viability of C. albicans When Exposed to CMC or Cellulose Phosphatea Exposure time (min) CFU/ml Control CMC Cellulose phosphate 0 1.12 × 105 1.07 × 105 1.12 × 105 15 1.29 × 105 1.27 × 105 1.35 × 105 30 1.31 × 105 1.14 × 105 1.18 × 105 60 1.27 × 105 1.29 × 105 1.66 × 105 210 8.45 × 104 9.97 × 104 1.35 × 105 a 210-min exposure n = 3.

RELEASE OF C. ALBICANS FROM SKIN 99 examination of triplicate tape strips. The CMC particles are believed to interact with the overall net negative charge of the skin cells, overcoming the combined adhesion forces and causing detachment of microorganisms adhered to the skin stripping. The removal of yeast from skin tape strips using CMC is highly effective and offers greater removal effi - ciency as compared to larger or alternative charged particles (Tables II and III). Anionic particles, in this model, were demonstrated to facilitate the release of yeast attached to skin tape strips (Tables II and III Figures 1–3) over a wide range of pH. Although the results of the t-test (CMC vs. PEI-Cellulose, p = 6.0 × 10−5 CMC vs. DEAE-Cellulose, p = 8.0 × 10−5 DEAE-Cellulose vs. PEI-Cellulose, p = 0.02) indicate that a larger sample size would be more informative, the CMC cellulose appears to per- form better than the other ion exchange materials. The difference observed between the DEAE-Cellulose and PEI-Cellulose would likely be eliminated with a larger sample size. The difference between the CMC and the other materials is very large and is anticipated to remain signifi cant even with a larger sample size. In combination with the visual ob- servation confi rming the loss of yeast from the skin tape strips treated with CMC, these results suggest that CMC shows greater potential for release of yeast cells than other ion exchange types under the conditions of this study. This process offers potential advantages over traditional cleaning compositions, in part, because the contaminant would be not merely dislodged from the skin surface, but would be fi rst dislodged and then removed from the skin’s surface through subsequent binding with the cleansing material. Therefore, interaction between contaminants and charge- altered cleaning compositions may involve an actual energy transfer as energy is released and recaptured in the dislodging and rebinding of contaminants from the skin surface to the cleaning product. CONCLUSIONS Delivery of negatively charged CMC particles to skin tape strips under the described conditions facilitates release of attached microorganisms and/or soil rapidly and over a Table V Visual Cell Counts of C. albicans on CMC Treated and Untreated Tape Stripsa CMC treated skin tape strips Untreated skin tape strips 840 ± 55 904 ± 25 a Average ± SD, n = 3, count per 2x107 μm2 No signifi cant difference between treated and untreated p = 0.264 (t-test). Table VI Reduction of C. albicans Attachment to Skin Tape Strips When Yeast and CMC Were Added Simultaneouslya CMC + Yeast Yeast 71 429 72 568 147 498 a Count per 2 × 107 μm2 30-min exposure.