Different Concentrations Of Acrylamide Research Articles

Molecular imprinting-electrochemiluminescence sensor based on Ru(bpy)32+@ZnO-Au composite for sensitive detection of acrylamide

In this work, a quenched molecularly imprinting-electrochemiluminescence (MIP-ECL) sensor based on Ru(bpy)32+@ZnO-Au nanocomposites was constructed to realize the sensitive detection of acrylamide (AM). Ru(bpy)32+@ZnO-Au nanomaterials show high ECL efficiency. AuNPs has excellent properties and can improve the properties of electrochemiluminescence by promoting the electron transfer process of the luminescent body. The MIP polymer film was formed on the surface of the material and eluted with eluent, leaving an AM imprinting cavity as a specific recognition site. When adding different concentrations of AM, it was specifically recognized by the MIP membrane, and the ECL signal decreased gradually, thus realizing the sensitive detection of AM. Under the optimal conditions, the detection ranges of the MIP-ECL sensor are 1–108 nM and the limit of detection (LOD) is 0.123 nM. Therefore, this sensor proposed in this work opens up a new way for the sensitive detection of AM in food.

The Oxidative and Anti-Angiogenic Effects of Acrylamide in Chorioallantoic Membrane Model

Objective: Acrylamide (ACR) formed spontaneously during the preparation of carbohydrate-containing foods by exposure to high heat and can be found in large amounts in processed ready-made foods like potato crisps, biscuits and crackers and bread. ACR is a toxic substance and increase oxidative stress. The aim of the study is to show the effects of acrylamide exposure at different doses on angiogenesis and oxidant-antioxidant balance in the chorioallantoic membrane model (CAM). 
 Methods: Two different concentrations of acrylamide is prepared (10-3 M, 10-4 M). Pellets were placed on the chorioallantoic membrane of the eggs. Before and after the experiment, liquid samples taken from the fertilized chicken eggs. 
 Results: ACR has an antiangiogenic effect which was dose-dependent. There is a significant increase in Total oxidant capacity (TOC) and oxidative stress index (OSI) values in 10-3 M ACR ve 10-4 M ACR groups, compared to the control group. Although there was a numerical increase in TOC and OSI values between the 10-3 M ACR and 10-4 M ACR groups, this increase was not statistically significant.
 Conclusion: This is the first study that investigates the antiangiogenic effects of ACR and one of the first studies that investigates oxidative stress on the CAM model. ACR exposure increased oxidative stress and showed antiangiogenic effect in the CAM model.

The in vitro Evaluation of Protective Effect of Rutin on Acrylamide Induced Oxidative Aging in NIH3T3 Cells

Background: Aging is one of the important factor in the development of age-related diseases. Acrylamide (ACR) can be produced during rich-carbohydrate foods preparing at high temperature. Recently, studies showed that ACR can induce cellular aging. Furthermore, Rutin is a natural flavonoid, which possesses a potent antioxidant activity. Objective: In this study, ptotective effect of Rutin (a potent antioxidant) on oxidative-induced aging after ACR exposure was evaluated. Materials and Methods: NIH3T3 mouse embryonic fibroblast cells were used for this study, which treated by different concentrations of ACR and H2O2. Oxidative stress was assessed by measuring of malondialdehyde and glutathion concentrations. To evaluate of the aging process, β-galactosidase activity was evaluated by enzyme staining and β-galactosidase activity assay kit. MTT assay was used to evaluate the viability of the cells. Results: Exposure of cells to ACR and H2O2 significantly decreased the cell viability and using of rutin significantly improved cell viability in cells treated by ACR (P<0.05). Rutin increased glutathion level in cells treated by ACR and H2O2 (P<0.05). Also, the rate of lipid peroxidation was significantly lower in the group treated with rutin and H2O2 than in the H2O2 group (P<0.05).The β -galactosidase activity was increased in H2O2 and ACR groups. The using of rutin with acrylamide significantly reduced the activity of β-galactosidase enzyme compared to acrylamide group (P<0.05). Conclusion: Based on this study, oxidative stress may be presented as an important mechanism in ACR induced-aging in NIH3T3 cells. On the other hand, Rutin, as a potent antioxidant, decresead aging by inhibition of oxidative damage.

Acrylamide Induced Oxidative Cellular Senescence in Embryonic Fibroblast Cell Line (NIH 3T3): A Protection by Carvacrol

Background: Stress-induced cellular senescence is a perpetual state of cell cycle arrest occurring in proliferating cells in response to stressful conditions. It is believed that oxidative stress plays a unique role in this process. As a reactive chemical compound that can induce oxidative stress, acrylamide is widely applied in several fields. Carvacrol is a liquid phenolic monoterpenoid found in essential oils of some plants and is known for its antioxidant and anticarcinogenic properties. Objectives: The current study aimed to evaluate the effects of carvacrol on oxidative stress and cellular senescence induced by acrylamide in the NIH 3T3 cell line. Methods: NIH 3T3 embryonic fibroblast cells were exposed to different concentrations of acrylamide, carvacrol, and H2O2 in a cell culture medium. The level of β-galactosidase (SA-β-gal) activity, as a marker of cellular senescence, was measured using staining and quantitative assays. Furthermore, to measure oxidative stress parameters, the content of glutathione and lipid peroxidation were determined. Results: Acrylamide could induce premature senescence evident by the elevated lipid peroxidation and SA-β-gal activity and declined cell viability and glutathione. Moreover, carvacrol showed beneficial effects on both acrylamide- and H2O2-induced cellular senescence by significantly reversing or subsiding the effect of oxidative stress and mediating its consequences. Conclusions: It can be concluded that carvacrol has protective effects against oxidative cellular senescence induced by acrylamide in the NIH 3T3 cell line.

The adverse effects of acrylamide exposure on the early development of marine medaka (Oryzias melastigma) and its mechanisms

Acrylamide (AA) can have deleterious effects on freshwater fish. However, its adverse effects on euryhaline fish are still unknown. In this study, embryos of Oryzias melastigma were exposed to different concentrations of AA to investigate its effect on early developmental disorders. After 21 days of exposure, AA significantly inhibited the hatching rate and delayed the hatching time of embryos, and led to developmental delay, teratogenesis, and locomotion impairments in larvae. RNA-sequencing data of larvae indicated that AA upregulated the expression of hemoglobin and myoglobin involved in oxygen transport and angiopoietin 1, integrin, and matrix metallopeptidases related to angiogenesis and downregulated the expression of early growth response genes and synaptotagmin-2 related to neural plasticity and neurotransmitter release. Overall, our study showed that AA caused deleterious effects on the early development of euryhaline fish through hypoxic stress and neurotoxicity, providing a scientific basis for the environmental risk assessment of marine AA.

Impact of Acrylamide on Cellular Senescence Response and Cell Cycle Distribution via an In-vitro Study.

Exposure to certain environmental toxins has been shown to be associated with cellular senescence mainly through induction of oxidative stress and impact on cellular systems. Acrylamide (ACR) has raised worldwide concerns regarding the high risk of human dietary exposure to its hazardous effect. Although there is ample evidence about the carcinogenicity of ACR, limited studies have focused on its impact on cellular aging. The levels of β-galactosidase (SA-β-gal) activity, cell cycle distribution, and the expression of the senescence-associated gene and inflammatory markers were evaluated following exposure of embryonic fibroblast cells to ACR. A significant elevation in SA-β-gal activity after exposure to different concentrations of ACR was accompanied by a considerably increased level of reactive oxygen species and lipid peroxidation. ACR-treated cells showed a noticeable decline in the total antioxidant capacity and thiol molecules. Moreover, the expression of cellular senescence-related genes including p38, p53, and p21 significantly upregulated at the high concentration of 5 mM ACR. ACR also induced G0/G1 phase arrest in embryonic fibroblast cells. The current study results revealed that exposure to ACR could enhance senescence response, contributing to increased oxidative stress and cellular damage.

In-Situ Synthesis of ZnO Nanoparticles using Gum Arabic Based Hydrogels as a Self-template for Effective Malachite Green Dye Adsorption

The current study focused on the use of gum Arabic grafted polyacrylamide (GA-cl-PAM) hydrogel as a self-template for the in situ synthesize of zinc oxide nanoparticles (ZnO NPs) and the application of synthesized nanocomposite as a potential adsorbent to remove synthetic dyes especially malachite green (MG) from aqueous solution. Different characterization techniques supported in situ synthesis of ZnO NPs onto polymer matrix. The gum Arabic-crosslinked-poly(acrylamide)/zinc oxide nanocomposites (i.e., GA-cl-PAM/ZnO nanocomposite) exhibited much better surface properties as compared to the parental hydrogel matrix. The swelling abilities of the GA-cl-PAM/ZnO nanocomposites with different concentrations of acrylamide were also checked and the nanocomposite with 7.03 × 10–4 mol/L of acrylamide exhibited maximum swelling capacity of 2354%. The nanocomposite adsorbed approximately 99% MG dye with 0.4 g/L adsorbent dose at neutral pH. Adsorption kinetics and isotherm followed pseudo-second-order and Langmuir isotherm models, respectively with the high adsorption capacity of 766.52 mgd/gads at 25 °C. It was observed that the dye molecules were adsorbed onto GA-cl-PAM/ZnO nanocomposite mostly via electrostatic interactions, hydrogen-bonding and pore-diffusion mechanisms. Diffusion of dye molecules within the internal structure of GA-cl-PAM/ZnO nanocomposite followed the combination of both liquid film as well as intraparticle diffusion mechanisms. Furthermore, nanocomposite was applied ten times consecutively to adsorb MG dye from aqueous solution. Therefore, GA-cl-PAM hydrogel have capability to be used for the in situ ZnO NPs synthesis and thus synthesized nanocomposite can be used effectively to treat dyes polluted wastewater.

Acrylamide-induced hematotoxicity, oxidative stress, and DNA damage in liver, kidney, and brain of catfish (Clarias gariepinus).

This study was carried out to explore the possible deleterious impacts of acrylamide (ACR) on catfish (Clarias gariepinus). The estimation of mortalities, the examination of the clinical picture, the evaluation of blood parameters, oxidative stress, DNA damage, and the histopathological picture were performed in the liver, kidney, and brain samples of the experimentally ACR-exposed catfish. The 96 hours LC50 value was estimated to be 133 mg/L by the hydrostatic method. Fish were reared in water containing four different concentrations of ACR as follows: 20%, 40%, 60%, and 80% of the estimated LC50 for 2 weeks. Abnormal behavioral, clinical, and postmortem responses were depicted. The anemic response including significant decreases in red blood cells, hemoglobin, and packed cell volume following the ascending concentrations of ACR were recorded. The malondialdehyde was significantly increased, whereas reduced glutathione level, superoxide dismutase, and total antioxidant capacity were significantly decreased. The DNA fragmentation assay illustrated a clear laddering pattern in all the tested organs. Notably, the brain was the most influenced organ. It is presumed that ACR contamination showed adverse impacts on the catfish.

Effects of Blood-brain Barrier and Simulated metabolic system on Apoptosis of SH-SY5Y Induced by Acrylamide in Vitro

Objective: To evaluate the effect of acrylamide on the apoptosis of nerve cells by integral cell modelling in vitro which simulates the barrier effect and metabolic micro-environment. Methods: A non-contact and co-cultured in vitro blood brain barrier (BBB) model was established by using human umbilical vein endothelial cells (HUVEC) and rat glioma cells (C6) . The trans-endotheilal electrical resistance (TEER) and horseradish peroxidase (HRP) tracer effects were measured to verify the tight connectivity and permeability of the established BBB model. An integrate discrete multiple organ cell co-culture (idMOC) model was established by inoculating the human renal cortical proximal tubular epithelial cells (HK-2) , human normal hepatocytes (L-02) and human neuroblastoma cells (SH-SY5Y) into the self-made multi-organ plate for co-culturing. Then the model was verified by observing the growth curve of various tissue cells under co-culturing or culturing individually. SH-SY5Y cells were exposed to different concentrations of acrylamide directly and indirectly (through BBB model and idMOC model) . The changes of cell apoptosis rate were analyzed by flow cytometry to explore the impact of model on Acrylamide (ACR) injury of typical neurotoxic agents. Results: HUVEC cells can form a wide range of close-connected complex and then inhibit the external electric field under the cross-endothelial movement, and the mean was lower than that of endothelial cell culture group at 4, 5 and 6 days (P<0.05) ; After 20 min, the penetration rate of HRP in the co-culture group was less than that in the individual culture group, and the difference was statistically significant (P<0.05) , indicating that the barrier function of the co-culture group was higher than that of the individual culture group. All cells can exchange substances through the exchange hole of the culture plate, the cells grow well and there was no obvious death. The growth curve in individual culture group and co-culture group were basically the same, the difference was not statistically significant (P>0.05) . Under the condition of different concentrations of ACR (140, 270 g/ml) , compared with the direct exposure group, the apoptosis rate of the BBB model and the idMOC model were significantly decreased, and the difference was statistically significant (P<0.05) . Conclusion: Based on HUVEC cells and C6 cells co-culture system, a blood-brain barrier model in vitro was established and based on co-culture of HK-2, L-02 and SH-SY5Y, the idMOC model was established. The toxicity and toxic action characteristics of ACR on SH-SY5Y cells were evaluated by validation tests.

Ecotoxicological Analysis of Acrylamide Using a Microalga as an Indicator Organism

Aquatic ecosystems are very prone to contamination. The fast and accurate assessment of the toxicity of water is an important tool for environmental safety. The aim of this study was to assess the possible toxic effects of acrylamide on physiological parameters of the Chlorophyceae Desmodesmus quadricauda. Cells in exponential growth phase were exposed for 72 h to different concentrations of acrylamide. Light microscopy analysis documented cell density, number of cells per coenobia, cell dimensions, and biovolume; chlorophyll a concentration was also determined. Result show that EC50 of acrylamide for D. quadricauda is 5.88 mg/L. Significant morphological changes were also observed for phenotypic plasticity and cellular dimensions. The most noticeable changes were the significant increase in one-celled coenobia over 24 and 48 h of exposure to EC50. These findings demonstrate that acrylamide may affect aquatic life, not only through growth inhibition, but also inducing phenotypic plasticity and also be problematic when used in high concentrations for water supply.

Synthesis and Studies on Water Swelling Behaviour of Polyacrylamide Hydrogels

SummaryThe polymerization was carried out under the different concentrations of acrylamide and crosslinker in an aqueous solution of NO2 gas as initiator at 50°C. The resulting polyacrylamide was saponified with NaOH solution. The hydrolysed polymers show high degree of water swelling (&gt;500) than that of unhydrolysed polymers (&lt;100). Swellability of the gel decreases with the increasing concentration of N, N’‐ methylene bisacrylamide − a crosslinker which enhances the degree of crosslinking in the polymer chains. The increased crosslinking restricts the expansion of polymer network which causes the lowering of the water absorbency. It was observed that polymer hydration increased with the molar mass of polyacrylamide. The swellability of polyacrylamide hydrogels is greatly lowered by the addition of ionic salts in the swelling medium. Both ionic strength and valency of the salts are responsible to decrease the water uptaking capacity of the gels which remain unaffected by nondessociating nature of urea. The hydrogels, so prepared, are stable and quite able to undergo swelling − deswelling cycles suggesting their reversible characters.

Urinary Metabolites as Biomarkers of Acrylamide Exposure in Mice Following Dietary Crisp Bread Administration or Subcutaneous Injection

Heat-treated carbohydrate-rich foods may contain high levels of acrylamide (AA). Crisp bread is a significant dietary AA source in the Nordic countries. We studied whether urinary metabolites of AA could be candidate biomarkers of AA intake and internal dose in mice following dietary crisp bread administration or sc injection. The crisp bread was experimentally baked to contain three different concentrations of AA: 0.19, 1.02, and 2.65 mg/kg, giving dietary exposures to AA of 0.024 +/- 0.002, 0.14 +/- 0.02, and 0.29 +/- 0.04 mg/kg bodyweight (bw)/day (mean +/- SD), respectively. A linear relationship was found between dietary AA exposure and urinary AA metabolites. On average, 55% of the ingested dose was recovered as urinary AA metabolites, and the molar proportions between the urinary metabolites showed similar proportions for the different doses. Urine AA metabolites were measured after sc injection of AA at doses of 0.05, 0.5, 5, and 50 mg/kg bw, and the urinary recovery for the three lowest doses was 54%. With the highest dose, 80% was recovered in urine, and the changed pattern of urinary metabolites indicated saturation of the metabolic conversion of AA to glycidamide. These results indicate that urinary metabolites of AA are good biomarkers of AA intake and internal dose up to 5 mg/kg bw/day. After sc injection of [(14)C]AA, 92% of the radioactivity was found in the urine and 2% in feces, liver, blood, and intestinal content (6% was not detected), demonstrating that sc AA was highly systemically available, that the major part AA metabolites was excreted, and that a significant portion of urinary AA metabolites (most likely glyceramide) was not accounted for by the present analytical method. Since the urinary recovery of AA after crisp bread feeding and sc injection was practically identical, an indicative "bioavailability" of AA from crisp bread was suggested to be approximately complete.

Structural and Functional Analyses of the Major Outer Membrane Protein ofChlamydia trachomatis

Chlamydia trachomatis is a major pathogen throughout the world, and preventive measures have focused on the production of a vaccine using the major outer membrane protein (MOMP). Here, in elementary bodies and in preparations of the outer membrane, we identified native trimers of the MOMP. The trimers were stable under reducing conditions, although disulfide bonds appear to be present between the monomers of a trimer and between trimers. Cross-linking of the outer membrane complex demonstrated that the MOMP is most likely not in a close spatial relationship with the 60- and 12-kDa cysteine-rich proteins. Extraction of the MOMP from Chlamydia isolates under nondenaturing conditions yielded the trimeric conformation of this protein as shown by cross-linking and analysis by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis with different concentrations of acrylamide. Using circular dichroism spectroscopy, we determined that the trimers were formed mainly of beta-pleated sheet structures in detergent micelles. Using a liposomal swelling assay, the MOMP was found to have porin activity, and the size of the pore was estimated to be approximately 2 nm in diameter. The trimers were found to be stable in SDS at temperatures ranging from 4 to 37 degrees C and over a pH range of 5.0 to 8.0. In addition, the trimers of MOMP were found to be resistant to digestion with trypsin. In conclusion, these results show that the native conformation of the MOMP of C. trachomatis is a trimer with predominantly a beta-sheet structure and porin function.

Acrylamide toxicity in isolated rat hepatocytes

Acrylamide (ACR) is an important industrial chemical used primarily in the production of polymers and co-polymers. Acrylamide is mainly neurotoxic to experimental animals as well as humans and has also been shown to be mutagenic and carcinogenic. The present study was designed to investigate the toxicity of ACR on isolated rat hepatocytes. The hepatocytes were isolated by collagenase perfusion method and were incubated with different concentrations of ACR (0.1, 1, 10 m m) for 2 hours. Cell viability by trypan blue exclusion and leakage of the enzymes such as alanine transaminase (ALT) and aspartate transaminase (AST) were determined. Reduced glutathione (GSH), glutathione S-transferase (GST) activity were also measured. A significant decrease in the cell viability was observed after exposure to 10 m m ACR for 30 min, while 1 m m ACR caused a significant decrease in the viability after 60 min. ALT leakage was parallel to the cell viability. AST leakage was significantly increased at 30 min of incubation with 10 m m ACR, whereas 2 hours of incubation was required for the leakage of AST from rats hepatocytes with 1 m m ACR. 10 m m ACR decreased significantly GSH as early as 30 min, while GSH level was decreased at 60 min after exposure to 1 m m ACR. Also, the GST activity increased with increasing the dose of ACR. Cytochrome P450 concentration was decreased after exposure to 10 m m ACR. The effect of ACR on cell viability, ALT and AST leakage, GSH and GST activity was time and dose dependent.

Concurrent grafting and dyeing of cotton with a acrylamide/potassium permanganate/citric acid system

Samples of loom‐state cotton fabric was treated with aqueous potassium permanganate solution at different concentrations in the presence of nonionic wetting agent. The samples were then washed and treated at various pH values using solutions containing different concentrations of acrylamide and citric acid, plus wetting agent and acid or direct dye at different times and temperatures. Critical fabric properties such as graft yield, colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend upon the concentrations of potassium permanganate, citric acid and acrylamide, as well as on the treatment pH and the duration of the treatment.

Attenuation of glyceraldehyde-3-phosphate dehydrogenase activity and ATP levels in rat brain synaptosomes by acrylamide.

The effect of neurotoxin acrylamide (AC) on energy metabolism has been studied in a purified preparation of the synaptosomes. The synaptosomes were prepared by the flotation technique in a discontinuous Ficoll/sucrose gradient. The purity of the synaptosomes was checked by electron microscopy and by assaying the activity of marker enzymes. By these criterias, free mitochondrial contamination in the synaptosomes was found to be > 2%. Incubation of the synaptosomes with different concentrations of AC (2.5, 5.0, and 10mM) produced a concentration-dependent inhibition (15, 35, and 60%, respectively) of glyceraldehyde-3-phosphate dehydrogenase activity. Acrylamide also produced a time-dependent decrease of ATP concentrations in the synaptosomes; about 25% loss of ATP was seen within 1h, while about 60% ATP was lost after 120 min incubation with 10 mM AC. The effect of known inhibitors of glycolysis-iodoacetic acid (IAA), and of oxidative phophorylation-rotenone and antimycin A, was also studied on ATP synthesis by the synaptosomes. IAA was found to be the most potent inhibitor of ATP synthesis, while both rotenone and antimycin A were equally effective in blocking ATP synthesis in the synaptosomes. These studies show that the synaptosome might be used as a suitable in vitro model to study the effect of neurotoxin such as AC on neuronal energy metabolism.

Acrylamide is genotoxic to the somatic and germ cells of Drosophila melanogaster

The genotoxic effects of acrylamide, a recently detected carcinogen, have been studied in the somatic (wing primordia) and germ cells of Drosophila melanogaster by the wing mosaic assay and the sex-linked recessive lethal test respectively. Larvae, 72 ± 4 h old, were exposed to 6 different concentrations of acrylamide ranging between 0.25 mM and 5.0 mM in instant medium for 48 h. It is observed that acrylamide is both mutagenic and recombinogenic in the wing disc cells and induces sex-linked recessive lethals.

Effect of gamma radiation on carbamoylethylated cotton

Carbamoylethylated cotton samples having 0·392, 0·524, 0·725, 1·379 and 1·546% N were prepared by reacting cotton cellulose in the fabric form with different concentrations of acrylamide in the presence of NaOH. The behaviour of these samples towards gamma radiation was investigated and compared with untreated cotton and alkali-treated cotton which was prepared under conditions similar to those of carbamoylethylation but in the absence of acrylamide. Irradiation was performed at different radiation doses (3·307–29·766 Mrad). Results of copper number and carboxyl content indicated that the carbamoylethylated cotton samples exhibited higher resistance to irradiation than the alkali-treated and untreated cotton samples. Furthermore, this resistance was higher the greater the extent of carbamoylethylation, expressed as % N. With respect to degree of polymerization, results suggested that the presence of the carbamoylethyl groups in the molecular structure of cotton cellulose impeded glucosidic bond scission, provided that these groups were present in relatively small amounts. This and the indication of differences between the tensile strength and elongation at break among the substrates examined were interpreted in terms of differences in microstructural features which, in turn, determine the susceptibility of each substrate to irradiation irrespective of the radiation dose used.

A longitudinal slicer for obtaining multiple uniform slices from cylindrical polyacrylamide gels

Construction of a longitudinal gel slicer for polyacrylamide gels is described. The apparatus produces intact, undamaged, and identical slices with rectangular cross section from gels of different thicknesses and different concentrations of acrylamide. When an extract containing brain proteins was electrophoresed on a cylindrical gel and then sliced and colored by Coomassie blue, an identical band pattern was obtained in all slices, indicating the absence of any gel distortion during cutting.

Anomalous Electrophoretic Behavior of a Cyanogen Bromide Peptide from Type III Collagen

The relationship between relative mobility on sodium dodecyl sulfate-polyacrylamide gels and the logarithm of molecular weight was linear for peptides derived by CNBr cleavage from purified collagen chains. One striking exception was found: when the CNBr peptide alpha 1(III)CB-8 was subjected to electrophoresis on a polyacrylamide slab gel calibrated with other peptides derived from the type III collagen chain, its relative mobility corresponded to a molecular weight of approximately 8,000. On a gel calibrated with globular proteins, its apparent molecular weight was 12,000. Its actual molecular weight, as determined by gel filtration and by amino acid analysis, is approximately 12,000. The dodecyl sulfate-protein binding ratio for this peptide did not differ from that of other collagenous peptides or globular proteins. Free electrophoretic mobilities and retardation coefficients were determined for selected collagenous peptides and globular proteins by electrophoresis on tube gels of different concentrations of acrylamide. By these indices, alpha 1(III)CB-8 resembled a globular protein rather than a collagenous peptide. Presumably, some difference in primary structure of this peptide results in conformational changes of its complex with dodecyl sulfate, such that the peptide-dodecyl sulfate complex behaves more like a globular protein than a collagenous peptide on polyacrylamide gels.