cis-Bis(2,2′-bipyridine-κ2N,N′)dichloridocobalt(II) trihydrate

Arun Kumar, K.; Amuthaselvi, M.; Dayalan, A.

doi:10.1107/S1600536811009251

metal-organic compounds

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Volume 67| Part 4| April 2011| Page m468

doi:10.1107/S1600536811009251

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cis-Bis(2,2′-bipyridine-κ²N,N′)dichloridocobalt(II) trihydrate

K. Arun Kumar,^a M. Amuthaselvi ^a and A. Dayalan ^a ^*

^aDepartment of Chemistry, Loyola College (Autonomous), Chennai 600 034, India
^*Correspondence e-mail: dayalan77@gmail.com

(Received 17 February 2011; accepted 10 March 2011; online 19 March 2011)

In the title complex, [CoCl₂(C₁₀H₈N₂)₂]·3H₂O, the Co(II) ion is situated on a twofold rotation axis and exhibits a slightly distorted octahedral geometry and is chelated by four N atoms of the two bidentate 2,2′-bipyridine ligands and two Cl⁻ ions. The crystal packing is stabilized by hydrogen bonding formed between chloride ions and adjacent water molecules. One of the two independent water molecules in the asymmetric unit is disordered over two sets of sites, each on a twofold rotation axis, in a 0.734 (17):0.269 (17) ratio.

Related literature

For the antibacterial activity of similar complexes, see: Senthilkumar & Arunachalam (2008 ). For similar complexes applied in the immunoassay of carcinoma antigen-125, see: Shihong et al. (2009 ). For the application of similar complexes as biosensors, see: Ying et al. (2006 ).

Experimental

Crystal data

[CoCl₂(C₁₀H₈N₂)₂]·3H₂O
M_r = 496.25
Monoclinic, C 2/c
a = 18.3644 (8) Å
b = 13.1902 (8) Å
c = 10.8854 (6) Å
β = 120.030 (4)°
V = 2282.8 (2) Å³
Z = 4
Mo Kα radiation
μ = 1.01 mm⁻¹
T = 293 K
0.30 × 0.20 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.721, T_max = 0.823
18022 measured reflections
2123 independent reflections
1731 reflections with I > 2σ(I)
R_int = 0.051

Refinement

R[F² > 2σ(F²)] = 0.045
wR(F²) = 0.143
S = 1.19
2123 reflections
152 parameters
4 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.67 e Å⁻³
Δρ_min = −0.65 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯Cl1	0.86 (6)	2.43 (5)	3.250 (4)	160 (5)
O1—H1B⋯Cl1ⁱ	0.85 (3)	2.37 (4)	3.218 (4)	172 (4)
Symmetry code: (i) $[x, -y, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and Mercury (Bruno et al., 2002 ); software used to prepare material for publication: PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811009251/bq2282sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811009251/bq2282Isup2.hkl

checkCIF report

Comment top

2,2-Bipyridine and 1,10-phenanthroline have been extensively used to form different complexes with transition metal ions in their various oxidation states. Tris(2,2'-bipyridine)cobalt(III) complexed with bovine serum albumin has been reported as biosensors (Ying et al., 2006). Bipyridine cobalt complexes were found to have considerable antibacterial activities (Senthilkumar & Arunachalam, 2008). The use of tris(bipyridine)cobalt(II) for immunoassay of carcinoma antigen-125 has been reported recently (Shihong et al., 2009).

The cobalt(II) ion has site symmetry 2 and assumes octahedral geometry with two symmetry related 2,2'- bipyridine ligands and two chloride ions. Cobalt(II) is linked to two 2,2'- bipyridine bidentate ligands via four nitrogen atoms and two chloride ions. The two 2,2'- bipyridine ligands are in cis position with mutually perpendicular to each other. The hydrated water molecules in the crystal packing helps the stabilization of crystal packing by forming hydrogen bonding between adjacent chloride ions.

Related literature top

For the antibacterial activity of similar complexes, see: Senthilkumar & Arunachalam (2008). For similar complexes applied in the immunoassay of carcinoma antigen-125, see: Shihong et al. (2009). For the application of similar complexes as biosensors, see: Ying et al. (2006).

Experimental top

The complex was prepared by adding a solution of 2,2'- bipyridine (0.01 mole) in 60 ml of acetone, to a solution of cobalt(II) chloride (0.005 mole) in 60 ml of acetone. The resulting solution was stirred for two hours, filtered and dried over vacuum desiccator to get red colour complex (yield 90%). The dark red colored crystals, suitable for x-ray analysis, were obtained by slow evaporation from alcoholic solution.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Bruno et al., 2002); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. ORTEP of [Co(bpy)₂(Cl)₂].3H₂O drawn with 50% displacement ellipsoid level. Water molecules have been omitted for clarity.
	Fig. 2. The crystal packing of [Co(bpy)₂(Cl)₂].3H₂O viewed along the c axis.

cis-Bis(2,2'-bipyridine-κ²N,N')dichloridocobalt(II) trihydrate top

Crystal data top

[CoCl₂(C₁₀H₈N₂)₂]·3H₂O	F(000) = 1020
M_r = 496.25	D_x = 1.444 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C2yc	Cell parameters from 6958 reflections
a = 18.3644 (8) Å	θ = 2.4–25.4°
b = 13.1902 (8) Å	µ = 1.01 mm⁻¹
c = 10.8854 (6) Å	T = 293 K
β = 120.030 (4)°	Block, red
V = 2282.8 (2) Å³	0.30 × 0.20 × 0.20 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	2123 independent reflections
Radiation source: fine-focus sealed tube	1731 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.051
ω and ϕ scans	θ_max = 25.6°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −22→19
T_min = 0.721, T_max = 0.823	k = −15→15
18022 measured reflections	l = −13→13

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.045	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.143	w = 1/[σ²(F_o²) + (0.0754P)² + 3.251P] where P = (F_o² + 2F_c²)/3
S = 1.19	(Δ/σ)_max < 0.001
2123 reflections	Δρ_max = 0.67 e Å⁻³
152 parameters	Δρ_min = −0.65 e Å⁻³
4 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0015 (5)

Crystal data top

[CoCl₂(C₁₀H₈N₂)₂]·3H₂O	V = 2282.8 (2) Å³
M_r = 496.25	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 18.3644 (8) Å	µ = 1.01 mm⁻¹
b = 13.1902 (8) Å	T = 293 K
c = 10.8854 (6) Å	0.30 × 0.20 × 0.20 mm
β = 120.030 (4)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	2123 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	1731 reflections with I > 2σ(I)
T_min = 0.721, T_max = 0.823	R_int = 0.051
18022 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.045	4 restraints
wR(F²) = 0.143	H atoms treated by a mixture of independent and constrained refinement
S = 1.19	Δρ_max = 0.67 e Å⁻³
2123 reflections	Δρ_min = −0.65 e Å⁻³
152 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
C1	0.9376 (3)	0.3673 (3)	0.5122 (5)	0.0632 (11)
H1	0.9858	0.3506	0.5089	0.076*
C2	0.8848 (3)	0.4410 (4)	0.4210 (6)	0.0774 (14)
H2	0.8973	0.4740	0.3583	0.093*
C3	0.8134 (3)	0.4643 (4)	0.4254 (6)	0.0772 (14)
H3	0.7768	0.5140	0.3658	0.093*
C4	0.7964 (3)	0.4142 (3)	0.5176 (5)	0.0610 (11)
H4	0.7476	0.4288	0.5202	0.073*
C5	0.8517 (2)	0.3418 (2)	0.6070 (4)	0.0428 (8)
C6	0.8377 (2)	0.2843 (2)	0.7097 (3)	0.0394 (8)
C7	0.7668 (2)	0.2959 (3)	0.7214 (4)	0.0518 (9)
H7	0.7247	0.3408	0.6623	0.062*
C8	0.7588 (2)	0.2405 (4)	0.8212 (5)	0.0599 (10)
H8	0.7120	0.2486	0.8319	0.072*
C9	0.8211 (2)	0.1730 (3)	0.9046 (4)	0.0576 (10)
H9	0.8171	0.1344	0.9725	0.069*
C10	0.8893 (2)	0.1635 (3)	0.8859 (4)	0.0472 (8)
H10	0.9310	0.1172	0.9419	0.057*
N1	0.92249 (18)	0.3194 (2)	0.6043 (3)	0.0449 (7)
N2	0.89867 (17)	0.2174 (2)	0.7915 (3)	0.0392 (6)
O1	0.8926 (3)	−0.0960 (3)	0.7511 (4)	0.0902 (12)
Cl1	0.92474 (5)	0.07552 (7)	0.56901 (9)	0.0448 (3)
Co1	1.0000	0.20323 (5)	0.7500	0.0367 (3)
O2	1.0000	−0.2593 (12)	0.7500	0.169 (6)	0.734 (17)
O3	1.0000	−0.4227	0.7500	0.174 (19)	0.269 (17)
H1A	0.911 (4)	−0.046 (3)	0.724 (5)	0.11 (2)*
H1B	0.904 (4)	−0.085 (4)	0.836 (3)	0.11 (2)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.043 (2)	0.068 (3)	0.071 (3)	−0.0005 (18)	0.023 (2)	0.021 (2)
C2	0.061 (3)	0.076 (3)	0.083 (3)	0.003 (2)	0.027 (2)	0.042 (3)
C3	0.057 (3)	0.062 (3)	0.088 (3)	0.011 (2)	0.018 (2)	0.036 (2)
C4	0.046 (2)	0.050 (2)	0.070 (3)	0.0110 (17)	0.016 (2)	0.0131 (19)
C5	0.0330 (17)	0.0354 (17)	0.0441 (18)	−0.0011 (13)	0.0074 (14)	−0.0034 (14)
C6	0.0301 (17)	0.0368 (17)	0.0399 (17)	0.0027 (12)	0.0089 (14)	−0.0068 (14)
C7	0.0332 (19)	0.059 (2)	0.051 (2)	0.0130 (15)	0.0122 (16)	−0.0016 (17)
C8	0.045 (2)	0.077 (3)	0.064 (2)	0.014 (2)	0.032 (2)	0.001 (2)
C9	0.049 (2)	0.074 (3)	0.053 (2)	0.0112 (19)	0.0282 (19)	0.007 (2)
C10	0.0359 (18)	0.055 (2)	0.0461 (19)	0.0082 (16)	0.0174 (15)	0.0074 (17)
N1	0.0331 (15)	0.0416 (16)	0.0487 (16)	−0.0004 (12)	0.0120 (13)	0.0027 (13)
N2	0.0265 (14)	0.0427 (16)	0.0394 (14)	0.0044 (11)	0.0098 (11)	0.0005 (12)
O1	0.101 (3)	0.110 (3)	0.064 (2)	−0.057 (2)	0.044 (2)	−0.018 (2)
Cl1	0.0335 (5)	0.0513 (6)	0.0415 (5)	−0.0071 (3)	0.0128 (4)	−0.0062 (3)
Co1	0.0238 (4)	0.0402 (4)	0.0382 (4)	0.000	0.0097 (3)	0.000
O2	0.133 (10)	0.217 (14)	0.117 (8)	0.000	0.032 (7)	0.000
O3	0.20 (3)	0.28 (5)	0.11 (2)	0.000	0.12 (2)	0.000

Geometric parameters (Å, º) top

C1—N1	1.327 (5)	C8—C9	1.373 (6)
C1—C2	1.381 (6)	C8—H8	0.9300
C1—H1	0.9300	C9—C10	1.373 (5)
C2—C3	1.370 (7)	C9—H9	0.9300
C2—H2	0.9300	C10—N2	1.329 (5)
C3—C4	1.362 (6)	C10—H10	0.9300
C3—H3	0.9300	N1—Co1	2.151 (3)
C4—C5	1.379 (5)	N2—Co1	2.132 (3)
C4—H4	0.9300	O1—H1A	0.86 (6)
C5—N1	1.348 (4)	O1—H1B	0.85 (3)
C5—C6	1.476 (5)	Cl1—Co1	2.4298 (9)
C6—N2	1.351 (4)	Co1—N2ⁱ	2.132 (3)
C6—C7	1.378 (5)	Co1—N1ⁱ	2.151 (3)
C7—C8	1.377 (6)	Co1—Cl1ⁱ	2.4298 (9)
C7—H7	0.9300

N1—C1—C2	122.8 (4)	C8—C9—H9	120.6
N1—C1—H1	118.6	N2—C10—C9	123.1 (3)
C2—C1—H1	118.6	N2—C10—H10	118.4
C3—C2—C1	118.2 (4)	C9—C10—H10	118.4
C3—C2—H2	120.9	C1—N1—C5	118.7 (3)
C1—C2—H2	120.9	C1—N1—Co1	125.8 (3)
C4—C3—C2	119.5 (4)	C5—N1—Co1	115.4 (2)
C4—C3—H3	120.2	C10—N2—C6	118.2 (3)
C2—C3—H3	120.2	C10—N2—Co1	125.5 (2)
C3—C4—C5	119.8 (4)	C6—N2—Co1	116.2 (2)
C3—C4—H4	120.1	H1A—O1—H1B	109 (5)
C5—C4—H4	120.1	N2—Co1—N2ⁱ	169.92 (15)
N1—C5—C4	120.9 (4)	N2—Co1—N1ⁱ	96.14 (11)
N1—C5—C6	116.1 (3)	N2ⁱ—Co1—N1ⁱ	76.58 (11)
C4—C5—C6	123.0 (3)	N2—Co1—N1	76.58 (11)
N2—C6—C7	121.4 (3)	N2ⁱ—Co1—N1	96.14 (11)
N2—C6—C5	115.7 (3)	N1ⁱ—Co1—N1	89.19 (16)
C7—C6—C5	122.9 (3)	N2—Co1—Cl1	91.72 (8)
C8—C7—C6	119.5 (3)	N2ⁱ—Co1—Cl1	95.26 (8)
C8—C7—H7	120.2	N1ⁱ—Co1—Cl1	171.64 (8)
C6—C7—H7	120.2	N1—Co1—Cl1	89.88 (8)
C9—C8—C7	118.9 (3)	N2—Co1—Cl1ⁱ	95.26 (8)
C9—C8—H8	120.6	N2ⁱ—Co1—Cl1ⁱ	91.72 (8)
C7—C8—H8	120.6	N1ⁱ—Co1—Cl1ⁱ	89.88 (8)
C10—C9—C8	118.8 (4)	N1—Co1—Cl1ⁱ	171.64 (8)
C10—C9—H9	120.6	Cl1—Co1—Cl1ⁱ	92.22 (5)

N1—C1—C2—C3	−0.8 (8)	C7—C6—N2—C10	−0.9 (5)
C1—C2—C3—C4	−0.5 (8)	C5—C6—N2—C10	180.0 (3)
C2—C3—C4—C5	1.0 (8)	C7—C6—N2—Co1	176.4 (3)
C3—C4—C5—N1	−0.3 (6)	C5—C6—N2—Co1	−2.7 (4)
C3—C4—C5—C6	−180.0 (4)	C10—N2—Co1—N2ⁱ	−136.3 (3)
N1—C5—C6—N2	1.5 (4)	C6—N2—Co1—N2ⁱ	46.6 (2)
C4—C5—C6—N2	−178.8 (3)	C10—N2—Co1—N1ⁱ	−93.0 (3)
N1—C5—C6—C7	−177.5 (3)	C6—N2—Co1—N1ⁱ	89.9 (2)
C4—C5—C6—C7	2.2 (5)	C10—N2—Co1—N1	179.3 (3)
N2—C6—C7—C8	1.9 (5)	C6—N2—Co1—N1	2.2 (2)
C5—C6—C7—C8	−179.1 (3)	C10—N2—Co1—Cl1	89.8 (3)
C6—C7—C8—C9	−1.5 (6)	C6—N2—Co1—Cl1	−87.3 (2)
C7—C8—C9—C10	0.3 (7)	C10—N2—Co1—Cl1ⁱ	−2.6 (3)
C8—C9—C10—N2	0.7 (6)	C6—N2—Co1—Cl1ⁱ	−179.7 (2)
C2—C1—N1—C5	1.5 (6)	C1—N1—Co1—N2	−179.5 (3)
C2—C1—N1—Co1	179.7 (4)	C5—N1—Co1—N2	−1.3 (2)
C4—C5—N1—C1	−1.0 (5)	C1—N1—Co1—N2ⁱ	7.5 (3)
C6—C5—N1—C1	178.7 (3)	C5—N1—Co1—N2ⁱ	−174.3 (2)
C4—C5—N1—Co1	−179.3 (3)	C1—N1—Co1—N1ⁱ	83.9 (3)
C6—C5—N1—Co1	0.4 (4)	C5—N1—Co1—N1ⁱ	−97.9 (3)
C9—C10—N2—C6	−0.4 (5)	C1—N1—Co1—Cl1	−87.7 (3)
C9—C10—N2—Co1	−177.4 (3)	C5—N1—Co1—Cl1	90.5 (2)

Symmetry code: (i) −x+2, y, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···Cl1	0.86 (6)	2.43 (5)	3.250 (4)	160 (5)
O1—H1B···Cl1ⁱⁱ	0.85 (3)	2.37 (4)	3.218 (4)	172 (4)

Symmetry code: (ii) x, −y, z+1/2.

Experimental details

Crystal data
Chemical formula	[CoCl₂(C₁₀H₈N₂)₂]·3H₂O
M_r	496.25
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	18.3644 (8), 13.1902 (8), 10.8854 (6)
β (°)	120.030 (4)
V (Å³)	2282.8 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.01
Crystal size (mm)	0.30 × 0.20 × 0.20

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.721, 0.823
No. of measured, independent and observed [I > 2σ(I)] reflections	18022, 2123, 1731
R_int	0.051
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.045, 0.143, 1.19
No. of reflections	2123
No. of parameters	152
No. of restraints	4
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.67, −0.65

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Bruno et al., 2002), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···Cl1	0.86 (6)	2.43 (5)	3.250 (4)	160 (5)
O1—H1B···Cl1ⁱ	0.85 (3)	2.37 (4)	3.218 (4)	172 (4)

Symmetry code: (i) x, −y, z+1/2.

Acknowledgements

The authors are grateful to Rev. Fr. Dr B. Jeyaraj, S. J., Principal, Loyola College (Autonomous), Chennai-34, India, for providing the necessary facilities and the Head, SAIF, IIT Madras, Chennai-36, India, for recording the X-ray data.

References

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